Download L227 Stick Insects

Stick Insects
L227
Stick Insects
L227
December 2002
December 2002
SCHOOL SCIENCE SERVICE
L227 Stick Insects
Contents
1.
Scope of this guide……………………………………………………………………………..
1
2.
Introduction……………………………………………………………………………………...
1
3.
Some basic information about stick insects (Phasmids)…………………………………...
1
3.1 The external anatomy of phasmids…………………………………………………
1
The life history of stick insects………………………………………………………………..
4
4.1 Eggs……………………………………………………………………………………
4
4.2 Nymphs………………………………………………………………………………..
5
5.
Phasmids suitable for schools………………………………………………………………...
6
6.
Housing requirements…………………………………………………………………………. 11
4.
6.1 Eggs…………………………………………………………………………………… 11
6.2 Nymphs………………………………………………………………………………..
11
6.3 Adults………………………………………………………………………………….. 12
7.
Feeding…………………………………………………………………………………………. 15
8.
General care……………………………………………………………………………………. 16
9.
Handling………………………………………………………………………………………… 16
10.
Surplus stock…………………………………………………………………………………… 17
11.
Holiday care……………………………………………………………………………………. 18
12.
Transporting stock for sale or exchange……………………………………………………. 18
13.
Diseases………………………………………………………………………………………... 19
14.
Educational uses of stick insects…………………………………………………………….. 19
14.1 Studying insect life cycles................................................................................. 19
14.2 Studying insect anatomy..................................................................................
19
14.3 Investigating stick insect movement................................................................. 20
14.4 Investigating stick insect physiology................................................................. 20
14.5 Investigating stick insect behaviour.................................................................. 21
15.
Appendix 1 Checklist of equipment for keeping stick insects………………………….… 24
16.
Appendix 2 Suppliers of livestock and equipment…………………………………..…….. 25
17.
Appendix 3 Sources of help and advice….………………………………………….……... 29
18.
Appendix 4 Publications……………………………………………………………….……... 30
19.
Appendix 5 A d-i-y cage for stick insects…………………………………………………... 32
20.
Appendix 6 Web sites dedicated to stick insects………………………………………….. 35
Strictly Confidential
Circulate to members and associates only
As with all CLEAPSS materials, members and associates are free to copy all or part of this guide for use in
their own establishments.
© CLEAPSS 2002
CLEAPSS School Science Service
Brunel University
Uxbridge
UB8 3PH
Tel: 01895 251496
Fax: 01895 814372
E-mail: [email protected]
Web site: www.cleapss.org.uk
L227 Stick Insects
1.
Scope of this guide
This guide provides information about choosing stick insects suitable for study in
schools and advice on how to maintain them in good health. It is intended for
teachers and other staff with little previous experience of keeping insects. Details
of suppliers of insects and equipment are given, together with a bibliography of
publications dealing with their breeding and care. Some suggestions for practical
work involving stick insects are also included.
2.
Introduction
Most children (and many adults!) are fascinated by stick insects. Their relatively
large size and ability to mimic the plants on which they live are unique in the
insect world. Despite these unusual features, they possess all the characteristics
of typical insects, making them ideal for study in schools. They have the
additional advantages of being straightforward to maintain, easy to breed and
relatively free from any significant health hazards. The majority of species are
generally harmless to both people and crops but a few types can nip, bite or
scratch. One species, the Florida walking stick, Anisomorpha buprestoides, can release a defensive spray that is irritating to the eyes. A recent report suggested
that people coming into extended and frequent contact with the insects may
develop an allergic response to the dust produced by their skins and frass. The
validity and significance of this claim has yet to be assessed.
Although it is illegal in the UK to release any non-indigenous creature into the
wild, if any stick insects do escape, they rarely survive for long enough to cause
serious problems. Nevertheless, care should be taken to ensure that no escapees
gain access to a heated greenhouse, since infestations have sometimes been reported in these circumstances.
3.
Some basic information about stick insects (Phasmids)
Stick and leaf insects belong to the insect order Phasmida, a group that includes
about 2,500 species. They are relatively large, nocturnal, tropical or subtropical
leaf-eating insects, the adults ranging in length from 20 mm to 300 mm. Their
closest relatives are cockroaches and mantids. The name phasmid derives from
the Greek word phasma, meaning spectre or ghost (from the way these insects
blend into their background). Their ability to mimic plant organs is legendary.
Adult insects resemble twigs or leaves and their eggs are strikingly similar in
appearance to seeds (although whether this is likely to help their survival is not
clear!). Their camouflage extends beyond mere physical similarity since they
often also behave like plant organs, remaining immobile for long periods or swaying in the breeze, mimicking the movement of vegetation.
3.1
The external anatomy of phasmids
Despite the unusual body forms shown by some stick insects, they display all the
basic characteristics of the major group – the Arthropods – to which they belong.
All have a tough outer skin, composed of the protein chitin that protects the body
from drying out and acts as a skeleton. This external skeleton (the exoskeleton)
supports and protects the body and forms a system of levers on which the
1
muscles act to cause movement. Much of the success of the arthropods can be
attributed to this exoskeleton, since it has enabled members of the group to live
and move on dry land, water and in the air. Its properties are also important in
determining the maximum size, strength and method of growth of members of
the group.
The body form of phasmids varies widely. Stick insects have elongated cylindrical bodies, although some have leaf-like side projections; the closely-related
leaf insects have flattened bodies and limbs. In many species, the surface bears
spines or more flattened projections that contribute to the camouflaged appearance of the insect. The following illustration shows the main external features
exhibited by most phasmids.
The external features of a stick insect
The head
The head bears a pair of simple, filament-like antennae, which in some cases can
be quite long. Males usually have longer antennae than females. All stick insects
have a pair of compound eyes, while those types that fly may have two or three
simple eyes in addition. The mouthparts are forward facing and designed to bite
off pieces of leaf. They consist of an upper lip (the labrum), a lower lip (labium), a
pair of jaws (mandibles) to chop the food and a pair of secondary jaws (maxillae).
The labium and maxillae bear sensory palps to taste the food and move it
towards the mouth. These structures are shown in the following diagrams.
2
A stick insect head viewed from below
Maxillary palp
Mandible
Labial palp
Eye
Labium
A stick insect head viewed from the left side
Simple eye
Compound eye
Antenna
Neck
Labrum
Mandible
Maxilla
Labium
Labial palp
Maxillary palp
The thorax
The thorax has three segments called (from the head end) the prothorax, mesothorax and metathorax. Each bears a similar pair of legs, although the rear pair
may be somewhat larger and stronger. The end section of each leg consists of five
parts called tarsi (singular – tarsus).
A typical stick insect limb
Trochanter
Femur
Tibia
Tarsus
Claw
The legs are relatively easily shed, a process referred to as autotomy. This mechanism allows the insect to escape capture or entanglement with minimum damage, since a replacement limb grows and enlarges each time a moult occurs (see
section 4). The tarsi of regenerated legs are 4- rather than 5-segmented.
The mesothorax and metathorax each bear a pair of wings. However, the wings
are reduced or lost in some species, especially the females. The fore wings and
the front portion of the hind wings are modified to cover and protect the folded,
flying part of the hind wings. Flying is possible in some species but is never
strong and usually consists of a fluttering glide.
The abdomen
Despite appearances, there are eleven abdominal segments. The first or ‘median’
segment is closely linked to the metathorax, while the eleventh merely consists of
a few projections attached to the last obvious abdominal segment. The ‘median’
segment is often important in classifying phasmids.
3
The external male organs appear as relatively small projections below segments 8
and 9. Females possess an ovipositor, a larger structure from which the eggs are
pushed out. The ovipositor consists of appendages from the 8th and 9th segments
concealed by a flap-like plate, the operculum, which is derived from the lower
covering of the 8th segment. These differences in shape can be useful in determining the gender of individual specimens.
In both sexes, there is a pair of unsegmented appendages arising from the rear of
the abdomen called the cerci (singular: cercus). These may be involved in the
mating process (see below).
4.
The life history of stick insects
The life history of stick insects consists of three stages: egg, nymph and adult.
4.1
Eggs
In some species, eggs are fertilised in the conventional manner by male insects
that are similar, although often smaller and differently coloured, to the female.
Both males and females may mate several times, the male standing on the back of
the female and tucking his abdomen around and underneath hers. At this point,
he may use his cerci to grip the female’s abdomen. He then transfers sperm to the
tip of the abdomen of the female in a small packet called a spermatophore. Sometimes, especially in larger species, the spermatophore falls to the bottom of the
cage after mating. Normally, however, it remains attached to the female and
sperm travel from it to a storage compartment at the tip of the female’s abdomen.
There the sperm are stored until eggs are produced. Sperm penetrate the eggs as
they pass by the storage chamber en route to the outside world.
A typical spermatophore
In some species, including the Indian stick insect, females regularly produce
fertile eggs without the need for fertilisation by a male, a process known as
parthenogenesis. Unsurprisingly, in these types, males are rare. In yet other species, fertilisation is usually conventional but parthenogenesis is possible in the
absence of fertile male insects.
Eggs are most commonly laid singly and dropped or flicked onto the ground.
The females of a few species deposit their eggs in loose soil while others glue
their eggs individually or in batches to leaves or branches. The number of eggs
4
produced depends on the species concerned and varies between 100 and 2,000 at
any one time. All have the same general structure. Their shape and texture often
resembles that of plant seeds. At the top is a lid-like operculum through which the
nymph hatches. The operculum may bear a small knob or capitulum that is used
by the female to hold the egg. At the side of the egg is a micropylar plate, looking
very much like the ‘scar’ on the side of a seed. This plate, along with the micropyle
(hole) that it surrounds, is probably concerned with water regulation and respiration by the embryo developing within.
The structure of a generalised stick insect egg
Capitulum
Operculum
Micropylar plate
Micropyle
Each egg contains a fatty liquid that nourishes the embryo during its development. Incubation time varies with temperature and between species; it can be as
short as a month or over a year.
4.2
Nymphs
The offspring from these eggs emerge in the form of nymphs that resemble the
adult but are smaller and lack wings. They then go through a series of stages
(usually about six), casting their skins between each one and becoming more
adult-like at each stage. Each of these stages is referred to as an instar. At each
moult or ecdysis, the body increases in length by about 25%. On reaching full size,
a final moult gives rise to the mature adult. Unlike the life history of, eg, butterflies and moths, there is no resting stage (chrysalis or pupa) between the feeding
and the adult stage, so metamorphosis in stick insects is described as incomplete.
On hatching, nymphs must rest while their exoskeletons harden. Once this is
complete, a period of great activity follows, during which they search about for
suitable food plants. At first, their only means of sustenance may be to drink
from tiny drops of water, but soon they begin to nibble at the food plants in order
to choose an acceptable type. As the nymphs increase in size, it becomes necessary for the entire exoskeleton to be moulted, a process that is repeated six or
more times before adulthood is reached. During moulting, the nymphs cling on
to an upright support (such as a suitable twig or the side of their cage). The first
visible sign of moulting is a change in appearance of the skin, which becomes
translucent. After some time, the insect inflates its body with air, almost doubling
its volume, as a result of which a split appears in the skin behind the head. The
insect then commences to pull itself out of its old skin, a process that can take up
to 2 hours. Once free, the soft new skin gradually hardens. It is very important
that the insect hangs freely at this stage and is not cramped or damaged, since
any resulting defects cannot be rectified until the next moult. An uneventful final
moult is therefore very important in ensuring that the adult is unblemished. It is
for this reason that a generously-sized cage is recommended. Obviously, insects
should not be moved about or otherwise disturbed during ecdysis. Once the pro5
cess is complete, the insect often eats the old skin, which is an important source
of protein. However, individuals that fail to do this still seem to develop
normally.
Once the adult emerges, a period of maturation must take place before mating
and egg laying can occur.
5.
Phasmids suitable for schools
A wide variety of stick and leaf insects is available through specialist suppliers
(see Appendix 2). The absolute beginner should start by keeping a commonly
available and easily cared for variety such as the Indian stick insect. This classic,
stick-like, wingless type has been in cultivation since 1898.
Carausius morosus - the Indian stick insect - easy to care for, if rather unexciting.
10 mm
During its years in cultivation, this species has acquired a tolerance of the
conditions typically found in centrally-heated classrooms and laboratories, so it
can normally be kept in unheated cages. It is also easy to propagate, since it
usually breeds by parthenogenesis. However, it is often considered to be rather
unexciting, since it is not particularly colourful, lacks wings and is inactive by
day. However, once experience has been gained by keeping a tolerant species
such as this, some of the more demanding types can be considered. These may
require higher levels of humidity and additional heating. Despite these additional requirements, most are by no means difficult to maintain. Leaf insects are the
most challenging members of the group to keep, since they require closelycontrolled conditions.
6
Extatosoma tiaratum - Macleay’s Spectre stick insect - ‘something more exotic!’
10 mm
Table 1 gives details of some of the more easily-kept phasmids available. It includes information about the temperature, humidity and nutritional requirements
for maintaining each of the insects listed. Information about temperature requirements should be used to decide whether normal room temperatures are suitable
for the species. If not, additional heating will be necessary.
The list of species is far from exhaustive and different suppliers stock different,
but equally suitable, types. When purchasing a type that is not listed in the table,
it is important to ascertain the geographical area and habitat from which it originated. It will then be possible to deduce the temperature and humidity level
needed to keep the animals healthy.
Heteropteryx dilatata - the Jungle Nymph - ‘something more aggressive!’
10 mm
7
TABLE 1
The general features of species of phasmid selected for their ease of care
Scientific
name
Common name
and origin
General form
Aretaon
asperrimus
Sabah or Thorny
stick insect
Brown and beige,
with spines on head
and thorax.
Borneo and the
Philippines
Bacillus
rossius
Mediterranean
stick insect
Corsica
Southern Europe
Baculum
extradentatum
The Annam stick
insect
Vietnam
Baculum thaii
Thai stick insect
Thailand
Size of adult
Temperature and
humidity
requirements
Food plants
General information and life cycle
statistics
47-58 mm
(1.8-2.3 inch)
74-86 mm
(2.9-3.4 inch)
Culture at room temperature (18-25 oC)
and high humidity
(60-80%). Spray daily.
Bramble (Rubus
fruticosus) and
oak (Quercus
sp.).
Provide sand or peat for egg deposition
and bark for the insects to hide under.
Eggs hatch after 3-4 months. Nymphs
mature in 6 months. Adults live about
9 months.
Green or brown
wingless, stick-like
insects. Short
antennae.
50-77 mm
(2-3 inch)
64-102 mm
(2.5-4 inch)
A temperature of
20-24 oC is required.
Does not need spraying with water. Ensure
good ventilation.
Bramble or
other Rosacea
(Hawthorn,
Crataegus etc).
Reproduces by parthenogenesis.
Eggs dropped onto the ground. They take
3-8 months to hatch. Nymphs mature in
2-4 months. Adults live 3-7 months.
Twig-like with
serrated legs.
Wingless.
70 mm
(2.7 inch)
77-107 mm
(3-4.2 inch)
Thrives at normal room
temperatures and tolerates dry conditions.
Use a well-ventilated
cage and spray once
or twice a week.
Bramble and
rose.
Exceptionally easy to rear. Eggs dropped
onto the ground, taking 1.5-2 months to
hatch. Nymphs mature in 4-6 months and
adults live a further 6 months.
Twig-like with
serrated legs.
77-107 mm
(3-4.2 inch)
118-178 mm
(4.6-7 inch)
Prefers warm conditions (21-27 oC). High
humidity helpful. Spray
daily.
Bramble,
raspberry and
eucalyptus.
An active species. Eggs dropped onto the
ground, taking 1-2 months to hatch.
Nymphs mature in 1.5-2 months; adults
live for 6 months. They are physically
delicate and readily shed their legs when
handled.
8
TABLE 1 (cont.)
The general features of species of phasmid selected for their ease of care
Scientific
name
Common name
and origin
General form
Carausius
morosus
Laboratory or
Indian stick insect
Dull green or brown,
wingless stick-like
insects.
Large, dark brown/
black. Very spiny.
Southern India
Eurycantha
calcarata
Giant Spiny stick
insect.
New Guinea.
Extatosoma
tiaratum
Macleay’s Spectre
or Giant Prickly
stick insect
Australia
A showy, leaf-like
insect. Males are
brown and slender.
Females are large,
brown, spiny insects;
weak flyers.
Size of adult
Temperature and
humidity
requirements
Food plants
General information and life cycle
statistics
69-77 mm
(2.75-3 inch)
Easy to keep at
normal room temperatures. High humidity
is not required but
light spraying once
or twice a week is
beneficial.
Privet (Ligustrum spp) and
Ivy (Hedera
helix)
The commonest species kept in schools.
Reproduces by parthenogenesis.
Eggs are dropped onto the ground and
hatch in 4-7 months. Nymphs mature in
4-7 months. Adults live 4-7 months. It tolerates relatively low temperatures, so take
care to prevent escapes!
100-125 mm
(4-5 inch)
120-153 mm
(4.7-6 inch)
Prefers temperatures
at the higher end of
the range 18-25 oC.
80% humidity is
required. Spray daily
and keep a shallow
dish of water in the
cage. Provide bark
for shelter.
Bramble, oak
Aggressive; keep apart from other
types. Eggs are laid in 2 cm deep peat. A
large propagator with a thick layer of moist
peat makes ideal housing. The eggs hatch
in 4-6 months, nymphs mature in 6 months
and adults live for about a year.
Normal room temperatures suffice. High
humidity not required.
Spray the food plant
daily but use a ventilated cage.
Bramble, oak
(especially
suitable for
nymphs), rose,
hawthorn and
eucalyptus.
77-115 mm
(3-4.5 inch)
100-153 mm
(4-6 inch)
Warning. Can draw blood if carelessly
handled. Not suitable to be kept by
young children.
Despite its exotic appearance, this stick
insect was usually considered relatively
easy to keep. Recently, however, there
have been reports that nymphs are dying
before completing their final moult. Inbreeding or parasitic attack have been suggested
as reasons for this change. The female
catapults the eggs to the floor of the cage.
They should hatch in 4-8 months. Nymphs
complete development in 3-4 months and
adults live about 6 months.
Warning. The spines can draw blood if the
insects are carelessly handled and can nip
the handler if disturbed. Not suitable to
be kept by young children.
9
TABLE 1 (cont.)
The general features of species of phasmid selected for their ease of care
Scientific
name
Common name
and origin
General form
Heteropteryx
dilatata
Jungle Nymph or
Malaysian stick
insect.
Males are dark brown
with long wings.
Females are apple
green, broad and
spiny.
77-88 mm
(3-3.5 inch)
145-160 mm
(5.7-6.3 inch)
Stick-like brown or
yellow-brown insects
with medium-sized
wings.
50 mm
(2 inch)
83-88 mm
(3.25-3.5 inch)
The Cameroon
Highlands
Sipyloidea
sipylus
Pink winged or
Madagascan stick
insect.
East India
Australia
Size of adult
Temperature and
humidity
requirements
Food plants
General information and life cycle
statistics
Best in heated surroundings 21-27 oC.
Needs humid conditions; spray food
plant daily and provide a shallow dish
of water. Avoid wellventilated cages.
Bramble.
Eggs are laid on or in moist sand and take
12-16 months to hatch. Nymphs mature in
about the same time and adults live for
12 months.
Tolerates a wide
range of temperatures from 16-27 oC.
Prefers a high humidity of about 70%.
Spray daily.
Bramble or
eucalyptus.
Will also eat
rose flowers,
oak, rhododendron etc.
10
Warning: Adults can draw blood by biting
or stabbing. Handle them frequently when
young to reduce such aggression. Not
suitable to be kept by young children.
Being winged, this species is useful in
showing basic insect characteristics.
Reproduction is normally by parthenogenesis. Eggs are glued to rough surfaces.
Cover the cage sides (especially the
corners) with corrugated cardboard to
receive the eggs. These will hatch in about
3 months. Nymphs mature in 4-6 months
and adults live for 6-9 months.
6.
Housing requirements
6.1 Eggs
The ideal container for hatching eggs is a small plastic box with a transparent lid.
Such boxes can be purchased from commercial suppliers (see Appendix 2)
although sandwich boxes and other items (such as the plastic boxes used to pack
Ferrero Rochet chocolates!) are equally suitable. These boxes protect the eggs
while allowing the contents to be easily checked for emerging nymphs. However,
in an emergency, any secure boxes can be used, although if they are opaque they
will need to be opened to check for hatchlings every day. Since the eggs and the
emerging nymphs of some species require ventilation, a number of small holes
should be drilled in boxes that have tight-fitting lids. The base of the container
should be covered with a layer of moistened horticultural sand about 1 cm deep.
According to their type, eggs should be placed on top of the sand or pushed
gently into it (see Table 1 for information). The boxes should then be labelled.
Thereafter the eggs should be kept moist by spraying them with water once or
twice a week. The resulting moist conditions may encourage the growth of
mould on the eggs. If this is suspected, Nipagin powder (methyl 4-hydroxybenzoate) should be sprinkled lightly onto the sand every few days. Mould
inhibitors such as Nipagin are sold by garden centres and some school science
suppliers. Alternatively, eggs that have been placed on the surface of the sand
can be gently dusted off using a soft paintbrush to remove any developing fungal
growth.
The incubation temperature should normally be the same as that provided for
adults and nymphs. Most eggs take several months to hatch. The time taken can
vary greatly, even between eggs that come from the same batch, so do not expect
all the nymphs to appear on the same day. The factors that determine this variation are not yet understood although moderate warmth is known to reduce the
time required for development.
6.2 Nymphs
As soon as the nymphs have emerged from their eggs and their skins have
hardened, they can be transferred to larger living quarters. In most cases this will
be the cage in which they will be housed as adults. However, if this is already
full or contains members of the more aggressive species such as Macleay’s
Spectre, the Jungle Nymph or the Giant Spiny stick insect, it will be necessary to
find some short-term housing until more suitable accommodation can be found.
This may simply consist of a plastic lunch box, although certain species (see
Table 1) will require some netting-covered holes to be cut in the lid for ventilation purposes. Since moulting nymphs require the height of their living quarters
to be at least three times their length, a taller cage will soon be required.
Newly-hatched nymphs are very fragile and often experience high rates of
mortality. Consequently, they need to be handled carefully; see section 9. They
move about actively looking for food and seek out droplets of water to drink.
Spray the food plant regularly and if the nymphs have difficulty in feeding, trim
back the edges of the leaves to expose some softer tissue. If that fails, try an
alternative food plant!
11
6.3 Adults
A variety of containers can be used for keeping stick insects. It is important to
choose housing to match the requirements of the particular species being kept.
Size. All stick insects require a cage of sufficient height to accommodate a good
supply of the food plant and to allow the nymph stages to shed their skin. Again,
the rule of thumb is to ensure that the height of the cage is at least three times the
length of the largest adult insect to be housed in it. Access to the inside of the
cage is necessary for cleaning purposes and for changing the food plant. Where
possible this should be provided though one of the sides, since adult insects of
some species often cling to the top of the cage, creating difficulties when the lid is
opened!
Ventilation. Some species require relatively low humidity. This is easiest to provide using a well-ventilated cage, with net-covered apertures on one or more
sides. Use fine, black entomological nylon netting glued in position to contain the
smallest specimens while allowing them to be easily seen. Appendix 2, Suppliers
of livestock and equipment, suggests sources of suitable netting and Appendix 5,
A d-i-y cage for stick insects, some useful adhesives. Tropical forest varieties need
higher temperatures, greater humidity and less ventilation. For these types, housing with solid walls is more suitable. Table 1 provides information about the
requirements of 9 commonly available species. Use this information to match
housing to its occupants. Reputable suppliers will provide similar information
about any other types of phasmid that they supply.
A wide range of containers has been pressed into use for housing phasmids,
including those listed below. Inventiveness and imagination know few bounds in
this area! However, it is important to ensure that the container used really will
provide the living conditions required by different types of stick insect.
•
Large jam or sweet jars with the mouth covered with fine meshed netting.
The mesh must be held securely in position with a large elastic band. Plastic
jars have the advantage that additional ventilation can be provided by
punching or cutting holes in the wall and covering them with netting.
•
Plant propagators with adjustable ventilators. These can be useful when
keeping phasmids that prefer warmer conditions, since they can accommodate a heating cable or pad. All the ventilators must be rendered phasmidproof.
•
Aquaria with suitably-adapted hoods in which the ventilation holes have
been covered with fine mesh. Because it is not essential for these tanks to be
watertight, old, cracked or metal-framed types are quite suitable and may be
obtained second hand for a very modest sum.
If a hood is not available, all that is necessary to convert aquaria to insect
housing is to tip them on end (to provide sufficient height) and cover the
open side with netting. If this arrangement is to be used for more extended
periods it is worth making up a light ‘door frame’ to which the netting can
be fixed. Such a door can then be hinged using self-adhesive tape, allowing
easy access for cleaning out and food plant replacement.
12
An aquarium adapted for housing phasmids
•
Old chemical balance cases. For insects that do not require high humidity
the sliding front can be replaced with a light netting cover (as above). Otherwise, very little adaptation is necessary.
•
Vivaria normally sold for reptiles and amphibians. These have the advantage that they have often been designed for use with heating cables or pads.
•
Butterfly cages. These consist of a wood- or wire-framed ‘box’ covered with
netting. Although suitable for temporary use, they are designed for liquidfeeding insects and some stick insects can chew through the netting. Sources
of these cages are given in Appendix 2.
•
Purpose-built cages. These can be purchased from scientific suppliers (see
Appendix 2, Suppliers of livestock and equipment) or alternatively can be constructed from inexpensive materials. They are capable of providing optimum
living conditions for stick insects.
There are two basically different types of manufactured cage: clear acrylic
cylinder cages and rectangular types usually with the door, back and roof
made of clear acrylic sheet and metal or nylon mesh side walls. Cylindrical
cages are well suited to the housing of insects requiring humid conditions;
rectangular types can be modified to cope with a range of humidity requirements. It is possible to construct either type of cage from d-i-y materials.
Instructions for constructing a ventilated cage are given in Appendix 5. Cylindrical cages can be made with two sheets of transparent acetate sheet (as
used for making overhead projector transparencies), fixed together to form a
tube using clear, self-adhesive tape. The resulting cylinder is taped to a flat
surface or fixed inside or around a circular biscuit ‘tin’. The top is covered
with netting taped into position or using the biscuit tin lid in which ventilation holes have been drilled or a ventilation panel cut out and covered with
netting.
13
A popular type of clear plastic cylinder cage
This is a good general-purpose cage, albeit
with little ventilation. It is particularly
suitable for insects requiring moderate to
high levels of humidity.
A d-i-y wood frame and netting cage
Two or three sides of this cage consist of
fine netting. Ventilation can be adjusted
by covering the netting sides with
plastic sheeting.
It is important to choose a suitable location for the cage. Although most stick
insects will survive (and many will flourish) in unheated cages, they must not be
subjected to rapid or extreme temperature fluctuations. The cage should therefore not be kept on a windowsill or directly over a radiator. The ideal position
would be in the corner of a room that is warm by day and cooler at night.
Heating
For many species, no additional warmth other than that provided by normal
room heating is necessary. Where warmer conditions are required, eg, by some
tropical species, the safest method of providing them is by a heater placed
underneath the cage, or buried beneath sand at its bottom. Suitable heat sources
14
for this purpose include mats or pads sold by garden suppliers for heating plant
propagators. Some of the mats or pads sold for heating vivaria are also suitable.
Although ceramic, infra-red emitters provide sufficient heat, they should not be
placed inside a cage because the holder and parts of the surface can become very
hot. Likewise, it is unwise to use infra-red heat lamps, spot lamps or even conventional light bulbs inside the cage because many of the insects that require
warmth also need a very moist atmosphere. Spraying the cage with water to raise
the humidity may result in the light bulbs shattering. Furthermore, many stick
insects are nocturnal and need a period of darkness to become fully active;
something that cannot be provided by a continuously-running light bulb. These
problems can be overcome by placing a lamp outside but close to the cage. The
lamp holder must be suitably-designed for the bulb being used, properly supported and electrically safe. An Anglepoise lamp is quite suitable for use with a
domestic light bulb and can be turned off by a timer switch for a few hours during the night. A maximum and minimum thermometer placed inside the cage
can be used to check whether sufficient heat is being supplied. Some of the more
expensive insect cages are supplied with a heater and thermostat but this refinement is not necessary for culturing the species mentioned in this guide.
7.
Feeding
Although most of the common species of phasmid will eat bramble leaves (Rubus
fruticosus), they do not form part of their natural diet. The chief exception is the
Laboratory or Indian stick insect, Carausius morosus, which eats privet leaves
(Ligustrum sp.). Fortunately, given a stout pair of gloves and some secateurs, both
of these plants are easy to obtain at most times of the year. The greatest difficulty
is likely to be experienced in early spring, when few mature leaves remain on the
stems and new growth is only just appearing. The young leaves of many plants
(including bramble) seem to be poisonous to phasmids and should be removed
from any material that is to be offered as food. It is therefore worth looking out
for bramble plants growing in sheltered places, since these provide the best
chance of obtaining a supply of mature leaves in late winter. With this difficulty
in mind, at least one commercial supplier offers to provide schools with suitable
bramble stems delivered on a weekly basis throughout the year.
Enthusiasts have experimented with a range of alternative foods, including wild
rose (Rosa canina), hawthorn (Crataegus monogyna), raspberry, oak (Quercus spp.),
Cotoneaster, ivy (Hedera helix), Rhododendron and Pyracantha. The shrub Hypericum
‘Hidcote’ (St John’s wort) is also reported to be well received and has the advantages of being semi-evergreen and free of thorns! Even apple peelings and lettuce
leaves have been accepted by some species when other food sources have failed.
If local supplies of bramble become scarce, it is worth trying out one or two of
these alternatives; the evergreen species are obviously particularly useful in
winter. Whatever the alternative food, it is, however, rare for a stick insect to
change its diet once it has established a food preference.
Avoid collecting plants growing close to roads or adjacent to crops that are likely
to have been sprayed with insecticides, since pollutants may harm your stock.
Once gathered, the vegetation must be prepared before being introduced into the
insect cage. Remove any dead leaves and twigs and all visible invertebrate life
such as snails, slugs and woodlice that could attack young phasmids. Then cut
15
off the dead bases of the stems and crush the newly-exposed ends before placing
them in water. This can be provided by using wet sand, moistened florists’ ‘oasis’
or simply a pot of water with the gap between stem and pot filled with paper or
cotton wool to prevent insects from drowning. Food plants should be regularly
checked for freshness but, treated in the manner described, they should last for
up to a week, or until they are consumed. When replacing the pot of old food
plants, check thoroughly for stick insects hidden on the twigs etc.
8.
General care
Most species require only very basic levels of routine maintenance. Whenever the
food plant is replaced, the cage should be cleaned out. To make this process
easier, cover the floor or table with a sheet of paper that is larger than the base of
the cage. This allows droppings, small nymphs and eggs to be collected up with
the minimum of fuss. Any eggs can be separated from the droppings by removing the paper and gently tipping it so that they roll towards one corner. They can
then be transferred to a suitable box for incubation; a small paintbrush can be
very useful for doing this. For species that lay their eggs in soil, a pot containing
a layer of moist peat or sand about 3 cm deep should be placed in the cage. Any
eggs laid in this pot should be gently separated out every few days and
transferred to fresh medium for incubation. Eggs that have been glued onto surfaces such as twigs can be removed with a damp paintbrush. Those fixed onto
leaves can be carefully cut free. In both instances the freed eggs should be transferred to a box as described in section 6.1. When cleaning out a cage, try to avoid
raising dust that might be inhaled.
Most phasmids benefit from a supply of water droplets on the surface of the food
plant and cage walls. This can be provided by lightly spraying with a hand
spray. This is available from some of the suppliers listed in Appendix 2. Similar
sprayers, designed for spraying foliar feed onto plants, are available from garden
centres. Alternatively, provided that they are very thoroughly washed out
before use, the pump-spray dispensers in which some domestic liquids such as
window and bathroom cleaning fluids are supplied will serve the purpose
equally well. Spraying should be carried out about once or twice a week for
temperate species. Those types that originate from tropical rainforests require
daily spraying to ensure suitable humidity levels within the cage. Do not soak the
cage and its contents, since this encourages mould that can be harmful to the
occupants. For the real enthusiast, humidity gauges can be obtained from garden
centres and laboratory equipment suppliers.
9.
Handling
As mentioned earlier, young nymphs are very delicate and need to be handled with
great care. If they need to be moved, they should be picked up using a soft brush or
gently encouraged to walk onto a piece of paper or other surface. They should not
be picked up with the fingers. Older nymphs and adults should also be handled
with care, since they easily shed their legs. The best strategy is to coax them onto the
hand rather than attempting to pick them up. If it is essential to lift them up, grasp
large insects by the middle of their bodies and medium-sized insects by their tails. A
few types can give a nip, bite or scratch and should be handled with respect and a
pair of gloves! Details of the more aggressive types are given in Table 1.
16
Eurycantha calcarata - Giant Spiny Stick Insect - ‘not for the beginner; large,
aggressive and needing warm, moist conditions’
10.
Surplus stock
Many species produce large numbers of eggs, and may reproduce by parthenogenesis. As a result, the numbers of offspring can soon become overwhelming.
The easiest method of controlling numbers is to dispose of the eggs. They cannot
simply be placed in the refuse bin, however, since this could be construed as
illegally releasing the insect into the wild. If they are prevented from hatching,
for example, by putting them into a plastic box or bag and placing it in a freezing
compartment for a few days, they can then be disposed of without concern.
Alternatively, it may be possible to ‘trade’ some eggs with other interested enthusiasts, although the market is well supplied with the commoner species. Since
insect eggs make a welcome addition to the diet of many aquarium fish, another
method of disposal is obvious!
Nymphs and adults can be more difficult to dispose of. Some may be donated to
interested students or sold to pet shops. They also make suitable food for any
carnivorous animals kept in captivity such as lizards, frogs, newts and spiders. The
last (and least popular) option is to carry out humane euthanasia. As with the
eggs, nymphs and adults can also be killed by placing them in an airtight container
in a freezer for a day or two. If no such means of chilling the insects is available, it
will be necessary to kill them using a chemical method. First, find a jar large
enough to hold the biggest of the insects to be treated. Choose a glass jar with a
tight-fitting glass, plastic or cork lid; a large coffee jar is ideal for most species.
Place a layer about 20 mm deep of well-bruised laurel leaves (Prunus laurocerasus,
not the variegated varieties) in the bottom of the jar and leave it firmly closed for 23 days before use. Such a jar should remain capable of killing insects for up to a
month; the leaves release hydrogen cyanide. For schools that have access to it,
ethyl ethanoate (ethyl acetate) IRRITANT p HIGHLY FLAMMABLE q provides a conv17
enient alternative to laurel leaves. Pour a few drops onto a pad of cotton wool
placed at the bottom of the jar. This chemical should be used and stored with care.
Use it in well-ventilated areas and be aware that its sweet smell can be addictive.
Consult CLEAPSS Hazcards 43 (or contact CLEAPSS for advice) to obtain the hazard data necessary to carry out a risk assessment.
An insect killing jar
11.
Holiday care
Stick insect cultures can survive half term and other shorter holidays without
attention. Try to avoid having large numbers of insects just before any long
school holiday. Recruit suitable carers in good time to look after the remaining
insects. This may require pupils to take the cages and their contents home with
them. If so, this needs to be organised well in advance so that parents can be
consulted and suitable transport arranged. Make sure to send home a brief information sheet with the insects. This should outline the care requirements of the
insects, including the collection and preparation of their food plant(s) and any
temperature and humidity requirements they may have. Warn parents to check
that the cages are properly sealed so that the occupants cannot escape and ruin
the houseplants!
12.
Transporting stock for sale or exchange
The cheapest and most convenient way in which to purchase phasmids is in the
form of eggs. Nymphs, and occasionally adults, are also offered for sale, but
these are progressively more expensive. Furthermore, nymphs do not travel as
well as eggs, while adults may only have a short life expectancy on arrival.
If personal collection or delivery is not possible, the best method of transport is to
send eggs through the post. Avoid sending them when cold weather is forecast,
since frost would certainly kill most of them. A convenient method of posting
eggs is to enclose them in a short length of relatively thick-walled plastic tubing
and stopper the ends with cotton wool (plastic plumbing pipe cut up into short
lengths is ideal). This arrangement is then fixed with self-adhesive tape to a piece
of card, placed in an envelope and sent by ordinary letter post. Provided the tube
is strong enough to prevent crushing, this method is likely to be very successful.
Alternatively, the eggs may be packed with cotton wool in plastic containers
such as those used to hold 35 mm film cassettes. These can then be placed in
stout envelopes and sent through the post in the same way that film is sent to
firms for development.
Sending nymphs and adults by mail or courier presents additional risks because a
suitable environment cannot be economically maintained within a parcel. Frosts
and periods of very hot weather are equally damaging to these stages in the
animals’ life history. If this form of delivery is unavoidable, the insects should be
18
packed into a stout, well-ventilated, escape-proof, cardboard box. The box should
be packed with dethorned food plant, the cut ends of which have been surrounded
with damp cotton wool and enclosed in polythene to retain the moisture. Sufficient
room should exist within the box to allow the insects to move freely about on the
food plant without being too cramped. The outer packing must be substantial to
prevent the package from opening in the post. Both the consignor’s and the
consignee’s addresses must be clearly written on the package, preferably with
telephone numbers. The whole package should then be labelled:
‘URGENT – BIOLOGICAL SPECIMENS - PLEASE HANDLE WITH CARE’.
13.
Diseases
Little is known about the diseases of phasmids. Fungal attacks may kill developing eggs, but the causes of the quite frequent ‘sudden deaths’ are still unclear.
Most of the problems encountered in keeping and rearing stick insects appear to
be the result of unsuitable housing conditions (incorrect humidity, overcrowding, poor food plant condition etc) rather than disease. Snails, woodlice and
spiders have all been known to attack phasmids at some stage in their life
history, which is why food plants should be carefully checked before being put
into their cages.
14.
Educational uses of stick insects
The value of stick and leaf insects in schools is greatly under-rated. They allow a
great deal of observation and investigation to be undertaken by pupils of all ages.
Here are some suggestions of activities from which to choose.
14.1 Studying insect life cycles
Stick insects provide good examples of the stages in incomplete metamorphosis,
contrasting well with those of butterflies, moths, beetles and many others which
have complete life cycles involving a pupal stage.
14.2 Studying insect anatomy
Although the adults retain many juvenile features, such as feeble wing development, phasmids nevertheless display all the basic characteristics of insects. Most
are relatively large and inactive by day, making them particularly easy to
observe and photograph. They make excellent material for developing the
observational skills of both primary and secondary school pupils. In addition,
moulting provides an excellent opportunity for pupils to observe and record a
process rather than a structure. The use of sequencing and illustrations to supplement written descriptions are useful skills that pupils will need to develop in
such recording work. Digital microscopes (eg, the Intel computer microscope) are
obviously invaluable in observing and recording such events.
The skin shed during ecdysis allows a detailed microscopical examination of different regions of the body to be carried out. Furthermore, many stick insects
(including the Indian stick insect) feign death when disturbed. In this state, the
surface of the exoskeleton can be studied in detail using a binocular microscope,
a hand lens or a digital magnifier.
19
14.3 Investigating stick insect movement
One major problem is that many stick insects remain fairly motionless by day,
which can make studying movement difficult! Unfortunately, the commonest
phasmid kept in schools, the Indian stick insect, is not only inactive by day but also
enters a completely torpid state if disturbed. Inert insects can be encouraged to
move by warming them in the hand and gently blowing on them, but this is not
always successful. Some species, such as the Thai stick insect, Baculum thaii, are
more active than most others, making them worth keeping for this reason alone.
In what order do insects move their legs?
This can be tackled as a group activity. Each leg of the insect must first be
identified by a letter or number. Pupils then choose one or more legs to observe,
calling out the letter or number as it is lifted from the ground. Another pupil acts
as group scribe, noting down the sequence of numbers as they are called out.
Alternatively, if the school has access to a suitable camcorder (or the Intel microscope used as a close-up viewer), a video can be made of the insect on the move.
Frame-by-frame analysis will then reveal the sequence in which the legs move.
Different insects can be compared to determine whether there is a fixed pattern
across the group. Do all species move in the same way? Some certainly sway
from side to side as they move, perhaps influenced by air currents.
What is the average stride length?
This is another job for the digital camera or camcorder. Place the insect on a sheet
of graph paper of sufficient area to allow the insect to take several strides. The
graph paper should be chosen to provide the clearest image possible, ie, dark
lines on white paper. A camera capable of taking a sequence of photographs in
succession should be firmly supported perpendicularly over the insect. If possible, focus the camera on the graph paper rather than the top surface of the insect
(the manufacturer’s instructions should be consulted for information about how
this can be achieved). Ensure that the field of view covers the entire anticipated
walking area. Take a sequence of pictures when the insect moves so that the
stride of each leg can be observed and measured against the background graph
paper on the resulting images.
14.4 Investigating stick insect physiology
The Animals (Scientific Procedures) Act regulates the type of experiments that can
be carried out on animals. It prohibits the carrying out of any procedure that
could result in a vertebrate (other than a human being) suffering pain, distress or
lasting harm, unless under licensed control. No such regulations apply to practical work carried out on invertebrates such as stick insects so the range of possible practical studies is wider, although no teacher would wish to encourage
callous behaviour towards living things. None of the studies suggested here is
thought to damage or cause the insects any great distress. However, scientific
literature does contain suggestions of studies that could do so. Pupils coming
across such accounts may wish to discuss the moral and ethical aspects of experiments on animals.
What factors affect the colour of stick insects?
The Indian stick insect is normally a dull green or brown colour. Its colouration is
due to green, orange and red-brown pigments in the skin, movement of which
enables the insect to adapt, over a period of a week or two, to the colour of its
20
surroundings. This can be investigated by keeping the insects in cylinder cages
covered with differently coloured paper. It is suggested that yellow or light-green
cages give rise to adults that are generally light in colour. Crimson or black cages
result in very dark brown insects and a blue background produces sepia-coloured
ones. Short-term colour changes are more difficult to detect because the nature of
the illumination and reflection from nearby surfaces can affect our colour judgement. Changes are most obvious if different regions of the insect body are subjected to different conditions (for instance, by masking a part of the abdomen with
opaque tape). It is also said that high temperatures and low humidity cause green
insects to become brown. There is scope here for further investigations of the influence of environmental factors.
Studies of growth
The obvious change in size observable at each moult of the nymph poses the
question: does a similar increase in mass take place at the same time? If an
accurate balance is available, a single insect can be weighed before and after each
moult. Records kept of the length of time between successive moults experienced
by previous generations of the species can be useful in planning the necessary
weighing programme.
If a sufficiently sensitive balance is not available, weighing a batch of insects and
working out the average provides a valid, if less accurate, method of monitoring
growth. A graph or chart of the results enables changes in mass during moulting
to be studied. Once a method for measuring the growth of an insect has been
devised, it can be used to study potential variables that might affect growth, such
as dietary changes, day length or temperature.
Quantity of food eaten
Direct measurement of the mass of leaf eaten each day by a phasmid would
require an extremely sensitive and consistent balance, since the quantities involved are small. It may be possible to measure the food intake of a group of
similar insects using this method and then work out the average but even this
would require a very sensitive balance to obtain reliable results. It is much
simpler to measure the area of leaf consumed. Select a healthy, active adult and
place it in a separate container together with its usual food plant. After a few
days, replace the food plant with a fresh twig from which all except two or three
leaves have been removed. Immediately prior to introducing them into the
container, the mass and total area of these leaves should be measured. The area
can be assessed by tracing around the leaves as accurately as possible onto graph
paper. After 24 hours, the leaf should be removed, remeasured and discarded,
ready for a repeat study using a fresh leaf.
Use the masses and area of the intact leaves to calculate the mass of leaf eaten by
the insect:
area of leaf eaten x total mass of leaves provided
total area of leaves provided.
14.5
Investigating stick insect behaviour
Observation of the flight reflex
Insects commence flying when their tarsi are not in contact with the ground. This
is an example of how adaptations have arisen to match an animal’s lifestyle. The
21
flight reflex can be shown by tying a thread around the thorax of a suitable insect
(ie, one with wings!). When the insect is lifted up, a reflex response immediately
causes the wings of the insect to carry out flying movements. If a piece of card is
then brought up until the feet come into contact with it, flight ceases. A camcorder or a digital camera capable of taking sequences of images can be used to
analyse the speed and nature of the wing beat.
Catalepsy
This is a defence mechanism employed by many stick insects, which may help to
reduce predation losses in the wild. When alarmed, the body of the insect
becomes rigid due to the contraction of most of the limb and body muscles. As a
result the insect adopts the form of a straight stick with the antennae pointing
forwards and the legs backwards. The insect can remain in this condition for long
periods. The condition can easily be demonstrated by rolling the insect very
gently with two fingers on a level surface. Gently pinching the hind end of the
thorax or warming the insect in the hand will break the condition.
Photohorotaxis
(Photo = light; horos = border; taxis = movement in response to a stimulus.) Since the
eggs of stick insects are often simply cast to the ground, the nymphs must possess some means of finding plant stems and climbing onto them. This can be
investigated using a large cylinder of white paper with some strips of black
paper to represent the stems of plants. After a few minutes, most nymphs will be
found near the border between light and dark areas. This is not movement directly towards or away from light (phototaxis); it is movement towards a junction.
Other responses
It is relatively straightforward to design fair tests to study the following activities.
(a) Food preference. Many stick insects will eat leaves from plants other than bramble or
privet. Their preferences may be studied by offering a number of similar insects a
choice of food plant and measuring the quantity of each type consumed. Reference
has already been made to alternative food plants that are known to be accepted by
some species; see Table 1. It may be necessary to allow the insects 2-3 days in
which to adjust to the new food before attempting to measure the quantity eaten.
Experience has shown, however, that many stick insects refuse to accept suitable
alternative food material once they have become ‘used’ to a particular plant.
22
Therefore, a further study is to correlate an ability to switch to alternative foods
with the age of the animals, ie, which nymphal stage has been reached.
(b) Factors involved in stimulating activity. Most stick insects are nocturnal and
become active in the evening. What light level triggers the increase in
activity? Or do the stick insects have an in-built ‘biological clock’ that determines when they become active? Movement may be detected by recording
the sound levels inside the insect cage using a suitable datalogging sensor
and software program. A position sensor could also be used to detect movement over a period of a day or so.
Attach a ventilated, translucent sandwich box to one end of a rotation sensor
bar. This can be achieved by cutting holes in one end of the box and passing
thick gardening wire through them to fix the box onto the arm. Put the largest
stick insect available, together with a few leaves from its usual food plant, into
the box and secure the lid. Place the entire set up in a warm, quiet place with
few draughts. Carefully balance the box on the arm using masses or pieces of
modelling clay.
A set up for detecting insect movement
Use the sensor and suitable software to record changes in position of the box
as the stick insect moves around. Investigate whether time of day and/or
light levels affect the activity of the animals.
23
15.
Appendix 1 Checklist of equipment for keeping stick insects
Details of the source of most of the specialist items listed below are given in Appendix 2, Suppliers of livestock and equipment.
Basic equipment
Use
Cage (large) for adults
Sufficiently roomy, with appropriate ventilation
to house the species being kept. (It must be at
least three times as high as the maximum
length of the adult insect.)
Cage for nymphs, smaller than
above
Only necessary if the main cage is unsuitable.
Can double as a holding cage for active
insects when main cage is being cleaned etc.
Fine netting or gauze
For covering large ventilation holes. Also
provides a surface for insects to climb on.
Gardening gloves and secateurs
For collecting and handling food plants.
Newspaper or tissue paper
For covering the floor of the cage and aiding
collection of eggs and droppings.
Nipagin or other mould inhibitor
To help prevent eggs from decomposing.
Pot of water, ‘oasis’ or moist sand
To keep the food plants fresh.
Reliable source of food plants
-
Small paintbrush
For handling eggs and very delicate nymphs;
also for dusting off eggs to help prevent
decay.
Small ventilated plastic boxes (clear)
For storing eggs.
For maintaining more demanding species
Humidity meter
Useful for checking the humidity in cages of
insects from tropical areas.
Maximum and minimum thermometer
To check that temperature fluctuations are not
excessive.
Heating device, eg, thermal pad or
mat, heating cable, infra-red or
domestic light bulb (with or without
thermostat)
For heating the cages of some tropical
species.
24
16.
Appendix 2 Suppliers of livestock and equipment
Note. At the time of writing this guide, the suppliers listed below indicated that various species of stick
insect were on sale. However, current stocks may sell out and new species may become available.
Always check with the supplier to ascertain the species that are available before placing an order.
Some of the suppliers listed produce a catalogue of their animals and products.
Local pet shops may also supply stick insects.
Blades Biological
Cowden
Edenbridge TN8 7DX
Tel:
01342 850242
Fax:
01342 850924
E-mail: [email protected]
Web site: www.blades-bio.co.uk
Stick insects supplied:
Aretaon asperrimus (Thorny1 or Sabah); Baculum thaii (Thailand); Carausius morosus (Indian); Menexenus maerens (Vietnamese prickly); Sipyloidea sipylus (Pink winged).
Other items supplied:
Plastic cylinder cage, net-covered butterfly cages, heat mats and thermostats.
Bugs Direct
2 Well Cottages
Devon TQ11 0JU
Tel:
01803 762409
Fax:
01803 762409
E-mail: [email protected]
Web site: www.bugsdirectuk.com
Stick insects supplied:
Acanthoxyla prasina (New Zealand prickly green); Acrophylla wuelfingii (Queensland titan); Extatosoma tiaratum (Giant prickly); Heteropteryx dilatata (Malaysian jungle nymph); Paraphasma rufipes
(Twig stick); Phaenopharos khaoyaiensis (Thailand giant walking stick); Sungaya inexpectata (Philippines).
Other items supplied:
None listed.
Virginia Cheeseman
3 Sutton Road
Heston TW5 0PG
Tel:
020 8572 0414
Fax:
020 8572 0414
E-mail: [email protected]
Web site: www.virginiacheeseman.co.uk
Stick insects supplied:
Anisomorpha monstrosa (Belize black); Aretaon asperrimus (Thorny or Sabah); Baculum extradentatum
(Annam); Baculum sp. (Thailand); Carausius morosus (Indian); Eurycantha sp. (Giant spiny); Haaniella sp. (Wood nymph); Heteropteryx dilatata (Jungle nymph); Lamponius guerini (Guadeloupe);
Libethra regularis (Trinidad miniature); Menexenus maerens (Vietnam prickly); Sipyloidea sipylus
(Pink winged); Sipyloidea sp. (Australian winged); Sungaya inexpectata (Sunny stick).
1
Throughout this section, the common names quoted are those that are used by the particular supplier concerned.
25
Other items supplied:
A range of clear plastic boxes, black nylon netting, vivarium heating mats, thermostats, thermometers, a humidity gauge and a good range of books about keeping phasmids.
Easy Insects
PO Box 107
Pontefract WF9 1YW
Tel:
01977 651187
Fax:
01977 644884
E-mail: [email protected]
Web site: www.easyinsects.co.uk
Stick insects supplied:
Acrophylla wuelfingii (Titan); Aretaon asperrimus (Thorny or Sabah); Carausius morosus (Indian);
Eurycantha calcarata (Giant spiny); Eurycantha coriacea (similar to giant spiny); Extatosoma tiaratum
(Macleay’s spectre); Heteropteryx dilatata (Jungle nymph); Medaura brunneri (Bangladesh); Phaenopharos khaoyaiensis (Thailand giant); Phasma gigas (Giant stick); Sipyloidea sipylus (Pink winged).
Other items supplied:
Vivaria; heaters; thermometers; humidity meters.
Griffin and George
Bishop Meadow Road
Loughborough LE11 5RG
Tel:
01509 233344
Fax:
01509 231893
E-mail: [email protected]
Web site: griffinandgeorge.co.uk
This company does not supply phasmids. It is a supplier of general equipment for school
science. Its catalogue includes a cylindrical plastic cage suitable for stick insects.
Philip Harris
Findel House
Excelsior Road
Ashby Park
Ashby de la Zouch LE65 1NG
Tel:
0845 120 4520
Fax:
01530 419492
E-mail: [email protected]
Web site: www.philipharris.co.uk
Stick insects supplied:
Carausius morosus (Indian); Extatosoma tiaratum (Macleay’s spectre).
Other items supplied:
Plastic cylinder cage; a rectangular ‘Bug cage’; a mist dispenser; pot for food plant with oasis.
Insectpets.co.uk
2 Ripon Close
Barns Park
Cramlington NE23 7XJ
Tel:
01670 738504
Fax:
E-mail: [email protected]
Web site: www.insectpets.co.uk
Stick insects supplied:
Baculum sp; Neohirasea (Vietnamese); Unknown sp. (Pink winged).
Other items supplied:
Plastic boxes, mist sprayer.
26
Phasmid Study Group
See Appendix 3 Sources of help and advice for details of this organisation. It is the major source of
less common-place species for the enthusiast.
Rep-tech
PO Box 1922
Windsor SL4 4ED
Tel:
01753 830444
Fax:
01753 831551
E-mail: [email protected]
Web site: www.rep-tech.co.uk
This company does not supply phasmids. It deals principally in reptiles and the equipment
necessary for culturing them. It supplies a wide range of infra-red heat lamps, heat mats, thermometers and a humidity gauge that are equally suitable for phasmid care.
Small-Life Supplies
Station Buildings
Station Road
Bottesford NG13 0EB
Tel:
01949 842446
Fax:
01949 843036
E-mail: [email protected]
Web site: www.small-life.co.uk
Stick insects supplied:
Aretaon asperrimus (Thorny or Sabah); Baculum extradentatum (Vietnamese or Annam); Baculum
thaii (Thailand); Carausius morosus (Indian); Eurycantha calcarata (New Guinea); Extatosoma tiaratum (Macleay’s spectre); Heteropteryx dilatata (Malaysian); Lamponius guerini (Guadeloupe); Neohirasea maerens (Vietnamese bark); Phaenopharos herwaardeni (Thailand straight); Sipyloidea sipylus
(Pink winged); Sipyloidea sp. (Thailand winged).
Other items supplied:
Two sizes of rectangular cage, egg-storage boxes, an adjustable mister and year-round supplies of
bramble. The company also publishes a useful publication Keeping Stick Insects (see Appendix 3).
Stickinsects.co.uk
131 Roundhill Road
St Andrews
Fife KY16 8HG
Tel:
01334 477385
Fax:
E-mail: [email protected]
Web site: www.stickinsects.co.uk
Stick insects supplied:
Carausius morosus (Indian).
Other items supplied:
Kits that include the basic items needed for starting and maintaining a culture of Carausius
morosus; a cylinder cage; mister and oasis.
Timstar Laboratory Suppliers Ltd
Marshfield Bank
Middlewich Road
Crewe CW2 8UY
Tel:
01270 250459
Fax:
01270 250601
E-mail: [email protected]
Web site: www.timstar.co.uk
Stick insects supplied:
Carausius morosus (Indian).
27
Other items supplied:
A supplier of general equipment for school science. Its catalogue includes a cylindrical, plastic
cage and a rectangular ‘Bug cage’.
Watkins & Doncaster
The Naturalists
PO Box 5
Cranbrook TN18 5EZ
Tel:
01580 753133
Fax:
01580 754054
E-mail: [email protected]
Web site: www.watdon.com
This company does not supply phasmids. A specialist supplier of a wide range of entomological
equipment, including netting, net cages and plastic boxes.
Worldwide Butterflies
Compton House
Sherbourne DT9 4QN
Tel:
01935 474608
Fax:
01935 429937
E-mail: [email protected]
Web site: www.wwb.co.uk
Stick insects supplied:
Aretaon asperrimus (Thorny or Sabah); Carausius morosus (Indian); Eurycantha calcarata (New Guinea); Extatosoma tiaratum (Macleay’s spectre); Neohirasea maerens (Vietnamese bark); Sipyloidea
sipylus (Pink winged).
Other items supplied:
Three different sizes of netting-covered rectangular cage (mini, standard and deep), two different
sizes of flat-pack, wooden-framed cages with netting sides, a large (9” x 12”) clear plastic cylinder
cage, a large Perspex-sided phasmid house, black nylon netting and plastic boxes in a variety of
sizes.
28
17.
Appendix 3 Sources of help and advice
The Phasmid Study Group
Membership secretary
Paul Brock
‘Papillon’
40 Thorndike Road
Slough SL2 1SR
Tel:
01753 579447 (after 5pm)
Fax:
E-mail: This group has a worldwide membership. It publishes a newsletter and journal and is by far the
best source of supply of stick insects for the enthusiast; some species will only ever be available
through the Group. However, to obtain phasmids from this source, one not only needs to be a
member, but a participating member! Whilst new members may be given surplus eggs of
common species, membership does not bring with it an entitlement to unlimited amounts of
scarce livestock. Instead, an exchange system operates. Members breed and produce a surplus of
one species to exchange for a starter culture of another. The different species are valued, enabling
the exchanges to be balanced by either quality or quantity. This ensures the whole group is selfsufficient in terms of adequate stock levels and availability of surplus material. If it is envisaged
that surplus eggs and culturing experience would not be returned to the Phasmid Study Group,
then membership should not be sought and phasmids should be purchased from one of the
dealers offering them for sale.
Amateur Entomologists' Society
PO Box 8774
London SW7 5ZG
Tel:
020 7942 5595
Fax:
E-mail: [email protected]
Web site: www.theaes.org
This organisation promotes the study and care of all types of insect, including phasmids. It
publishes a range of authoritative academic texts on a variety of topics together with a bimonthly
members’ journal, the Bulletin, and a bimonthly magazine for younger members, the AES Bug
Club Magazine.
Membership types:
Ordinary
Ordinary members receive the Bulletin six times per year and Invertebrate Conservation News three
times per year. £15.00 per annum.
Junior
Junior membership is for the under-18s. Juniors under 11 receive the AES Bug Club Magazine;
those between 11 and 12 receive both the Bulletin and AES Bug Club Magazine. Those aged over 13
receive just the Bulletin. £8.00 per annum.
Family
This entitles the member to both the Bulletin and the AES Bug Club Magazine. £20.00 per annum.
Associate
This category of membership is for schools, societies, libraries and other institutions. Subscription
is the same as for Ordinary or Family membership depending upon the publications required, ie,
£15.00 or £20.00 per annum.
29
18.
Appendix 4 Publications
Where a publication can be purchased directly from a publisher, contact details are given. Otherwise, orders should be placed with your usual supplier.
BOOKS
For further titles of books on stick insects written for children, visit the web site: www.amazon.
co.uk and search for ‘stick insects’. This should reveal additional titles (often American) to those
listed below.
A Step-by-Step Book about Stick Insects
Alderton, D. 2002
ISBN 0866223495
£2.85
TFH Publications
A beginner’s book, well illustrated in colour; short notes on 6 species and mention of others. 64
pages, hardback, 220 mm x 145 mm.
Rearing Stick and Leaf Insects
Baxter, R.N. 2002
ISBN 0951921932
£22 (plus £1.50 p&p)
Chudleigh Publishing
45 Chudleigh Gardens
Seven Kings
Ilford IG3 9AT
A very comprehensive hardback publication with 112 colour photographs, descriptions and culturing details of 49 species. A photograph and description of each species is followed by helpful
information about breeding and maintaining stocks. This is definitely a book for the enthusiast
rather than the beginner.
Rearing and Studying Stick and Leaf Insects
Brock, P.D. 1992
ISBN 0900054549
£5.20 (including p&p)
AES Publications
1 Tower Hill
Brentwood
Essex CM14 4TA
Tel:
01277 224610
Fax:
01277 262815
E-mail: [email protected]
A low-cost guide for the beginner or more experienced rearer, with detailed notes on 17 species
widely bred in captivity and brief notes on over 55 other species. 79 pages with figures and black
and white plates. Paperback A5.
The Amazing World of Stick and Leaf Insects
Brock, P.D. 1999
ISBN 0900054638
AES Publications
(see above)
£15.20 (including p&p)
A comprehensive guide to everything you want to know about stick and leaf insects. Although
suitable for beginners, it provides a wealth of information to interest the enthusiast. Contents
include fascinating facts, life history and development, collecting, preserving, breeding, taxonomic studies, notes on species from around the world and fossils. 182 pages with numerous
figures/black and white plates + 40 pages of colour plates. Hardback A5.
30
A Complete Guide to Breeding Stick and Leaf Insects
Brock, P.D. 2000
ISBN 1852791241
TFH Kingdom
£12.95
This book has comprehensive notes on 11 commonly-reared species, plus numerous colour
photographs of these and other species. It is suitable for the beginner or more-experienced rearer.
In addition to information about breeding, there are useful sections on housing, feeding and
trouble-shooting. 64 pages, hardback.
Keeping Stick Insects
Floyd, D. 1994
ISBN 0951246607
Floyd Publishing (from Small-Life Supplies - see Appendix 2 Suppliers of livestock and equipment)
£6.99 (plus £4.94 p & p)
This is written in an easy style and includes a general description of the anatomy and behaviour
of stick insects in general with insightful descriptions of the care of 7 common species. Line drawings are supplemented with 8 colour photographs. 60 pages, paperback.
Bug Books: Stick Insects
Hartley, K. & Macro, C. 1999/2000
ISBN: hardback 0431016860; paperback 0431016941
Heinemann Library
Price £8.99 hardback or £5.50 paperback
Answers to a number of simple questions, illustrated with colour photographs, designed for primary schools; 32 pages. Although some information is inaccurate, it contains some interesting
pictures.
VIDEO RECORDING
Stick and Leaf Insects. A Novice’s Guide to Keeping Phasmids
VHS/PAL. £12.00 including p&p.
GK Video
PO Box 213
Grimsby DN36 5ZG
Tel:
01472 811808
Fax:
01472 811808
Email:
Web site: A well-made, 32 minute video, containing much good advice.
31
19.
Appendix 5 A d-i-y cage for stick insects
An exploded view of the component parts
To make this cage you will need the following materials.
Quantity
Item
Dimensions
A
1 piece
Melamine-coated chipboard
300 mm x 284 mm x 15 mm
B
1 piece
Melamine-coated chipboard
300 mm x 300 mm x 15 mm
C
1 length
Softwood, painted gloss white
260 mm x 10 mm x 10 mm
D
1 length
Softwood, painted gloss white
200 mm x 10 mm x 10 mm
E
4 lengths
Softwood, painted gloss white
600 mm x 20 mm x 20 mm
F
2 lengths
Softwood, painted gloss white
630 mm x 20 mm x 10 mm
G
1 piece
6 mm thick glass with polished edges
600 mm x 300 mm
-
8
Chipboard screws
40 mm
-
8
Screw caps for above
-
-
8
Panel pins
10 mm
-
1 piece
Nylon mesh or net curtain material
Enough to cover three sides of
the cage
-
1 tube
Woodwork adhesive
-
-
1 piece
Hardboard
30 mm x 15 mm
-
1
Round-headed screw with washers
25 mm
32
Assembly instructions
(Note: You may need to adjust the dimensions of items given in the table overleaf, depending on the materials available locally.)
1
Fix the four pieces of timber E to the corners of the underside of A, using
chipboard screws. Countersink and cap the heads.
2
Fix item C to fit between the front uprights. Use adhesive and four panel
pins to fix it in position as shown above.
Screw the other ends of uprights E to the base, B, so that one pair is 15 mm
from the front edge as shown below. Again, countersink and cap the screws.
3
4
5
Fix the wood strip D in the same way as C, positioning it in the centre of the
space between the two uprights E.
Make sure all sharp edges on the glass have been polished by the supplier.
Carefully place it in position; it may be necessary to twist the framework so
that it fits snugly.
33
6
7
8
9
Glue the timber strips F to the top (A) and base (B) [as shown in the diagrams overleaf] on each side of the glass, to stop it sliding out from the sides
of the cage.
Use the piece of hardboard and round-headed screw to make a catch to hold
the top edge of the glass in place.
Cut out three pieces of nylon mesh or net curtaining material to fit over the
back and sides of the cage. Glue them in position using adhesive such as
UHU Contact, Evostik Safe 80 or Time Bond. Alternatively, a cool-melt glue
gun can be used.
When keeping insects that require high humidity, one or more sides can be
covered with polythene or acetate sheet, in place of or in addition to, the
netting. It can be fixed with glue or held in place with strips of wood fixed
to the uprights (E) with panel pins.
34
20.
Appendix 6 Web sites dedicated to stick insects
There are many web sites set up by commercial organisations as well as individual enthusiasts. This is a developing area and subject to rapid changes. A visit to
the web site of one of the established organisations will soon lead you on to other
specialist sites. In addition to the sites listed under entries in Appendices 2 and 3,
the following may be of interest.
Amateur Entomologists' Society
www.theaes.org
Australian Museum Phasmid
Factsheets
www.amonline.net.au/factsheets/phasmids.htm
Bug Club
www.ex.ac.uk/bugclub
Bugs in Cyberspace
www.bugsincyberspace.com
Earthlife
www.earthlife.net/insects/
Field Guide to the Stick Insects of
Australia
www.acay.com.au/~pmiller/
Phasmid Study Group
www.stickinsect.org.uk
The Sticklist
www.exotics.net/sticklist/
Tony & Charlotte’s Stick Insect Page
www.woodbat.co.uk/stick.htm
Tree of Life (search for ‘phasmid’)
www.tolweb.org/tree/phylogeny.html
35