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Biological Sciences
January 1986
The genera of Elatinaceae in the southeastern
United States
Gordon C. Tucker
Eastern Illinois University, [email protected]
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TUCKER, ELATINACEAE
THE GENERA OF ELATINACEAE IN THE
SOUTHEASTERN UNITED STATES
1
Gordon
ELATINACEAE
Tucker
C.
2
Dumortier, Anal. Fam. PL 44, 49. 1829, "Elatinideae,"
(Waterwort Family)
50 cm tall) of aquatic or moist terrestrial
lower nodes usually with adventitious roots. Plants
Annual or perennial plants (up
habitats.
Roots
fibrous;
to
glabrous or glandular pubescent throughout, with unicellular or multicellular
multiseriate capitate trichomes. Leaves opposite or decussate, entire or coarsely
stomata anomocytic; stipules scarious. Flowers small, actinomorphic,
3
serrate;
lablished in the
first
V
>,h
»n
19S8) and continued
\h
North and South Carolina, Georgia, \
Alabama, Mississippi, Arkansas, and Louisiana. The descriptions are based prim;
he area covered by the
,
nold
(Inn,
p..
<
•>
nei
ic
i
lora in< hides
1
I
thanl.
,
Wood
Norton Miller and Carroll
for
oppo. tunities provided by the Generic Flor;
Hi.
icr.
s
help in the development
;rest in the
Elatinaceae by
Thomas
.
L.
ihepres.
c,1
Wilbui
.itiesofth.
:
iced Systematics course a
ppropriate topic for a rese;
libraries ol
the -\rnoii
••
titutoBotam
helped co
'Roloe i<
ii
;up
New
\
ork State
Museum. The
Pursh) Arnott — (
'i.
)
/
,,
,
onnnin
un
(Hook..) Seub
.
L
I
oi
l-i
in
n
in,
/
*
on,
I'.d
n
i
i
oln
an
Ii
;
(
Viii
(>
i
o (nyk).
o
.
m
dl
nl
,
Hnl^poii
»>,i
Meyer-Connecticut, Lyme, Tucker A Linkc J!
(
i
State E< liuauonIVp. rl
,
New Yor
U>°(<
and Ston
/uivi/id
l
.
Hoi
in)
JOURNAL OF THE ARNOLD ARBORETUM
472
hypogynous, borne singly or
5 [or 6], free or barely
[2 or] 3-6[-10], in
1
in
[vol. 67
small clusters in the axils of leaves. Sepals 2-
united basally. Petals membranaceous, 2-5,
free.
Stamens
or 2 whorls, the outer whorl alternate with the petals;
anthers broadly ovoid, dehiscing by longitudinal
spheroidal, tricolporate, 2- or 3-nucleate
when
slits;
shed.
pollen prolate to sub-
Ovary
[2 or] 3-5-locular,
ovoid to depressed ovoid; placentation axile or basal, the partitions not reaching
the summit of the ovary in some species of Bergia; ovules numerous, anatropous, bitegmic, tenuinucellar; megagametophyte (embryo sac) of the Polygonum type. Fruit a thin-walled septifragal capsule. Seeds ellipsoid to oblong,
0.5-1
.5
mm long, with finely reticulate [smooth] surfaces; endosperm very
embryo straight, filling nearly the entire seed; germination
Base chromosome numbers 6, 9. Type gi nus: Elatine Linnaeus.
or none;
A
little
epigeal.
two genera, Bergia L. and Elatine,
and about 35 species. Both genera are represented in the United States. One
species of Bergia and two of Elatine occur in the Southeast.
small, nearly cosmopolitan family of
The
Elatinaceae are herbaceous or suffrutescent aquatic or wetland plants
with opposite [whorled] simple
interpetiolar stipules.
[tripartite or quadripartite] leaves
The inconspicuous two-
nomorphic flowers are borne
with paired
to five- [or six-]merous acti-
singly or in dichasia in the
small, thin-walled capsular fruits are septifragal,
upper leaf axils. The
and the seed coats are char-
aclenstically strongly sculptured.
Adanson noted a
between Elatine and the Caryophyllaceae in their
opposite leaves, small flowers, and tiny seeds. This view was also held by De
Jussieu, De Candolle, Bentham & Hooker, Bessey, and Hutchinson. As early
as 1 827, however, Cambessedes noted similarities between the Elatinaceae and
similarity
the Guttiferae {sensu lata, including the Hypericaceae). Gray, in his discussion
of the taxonomy of the family, emphasized its similarities to the Guttiferae.
Niedenzu, and
Melchior
succeeding editions of Engler's Syllabus, placed
the family in the Parietales. Cronquist, Takhtajan, and Thorne concurred in
later
in
the placement of the Elatinaceae in the Theales
and agreed
that
its affinities
with the Guttiferae (Clusiaceae). Corner noted a similarity in the structure
of the seeds of the two families. The sculpturing of the seed coat in the Elatinalie
ceae
is
very
much
like that
of Guttiferae subfam. Bonnettioideae, particularly
the genus Ploiarium Korth.
The wood anatomy of Bergia suffruticosa Fenzl
relationship of the family
indicates that the
most
likely
with the Guttiferae (Carlquist). The following
similarities arc apparent: occurrence of simple perforation plates, presence of
vasicentric tracheids
is
and fibriform
vessel elements,
predominance of uniseriate
of scalariform vessel-ray pitting, absence of intraxylary phloem, presence of brownish compounds [tannins?] in the parenchyma,
and occurrence of druses and solitary crystals.
Melikian & Dildarian, on the basis of anatomical and palynological studies,
rays, vertical orientation
and Walia
& Kapil, on the basis of embryological studies of the Frankeniaceae,
a family usually placed in the Parietales, concluded that the Elatinaceae and
the Frankeniaceae are closeh r<
ted
lowi er, because several of the simiI
larities
they listed
(e.g.,
I
trinucleate pollen, bitegmic ovules,
and monosporic
TUCKER, ELATINACEAE
1986]
embryo
sacs) characterize
many
473
families of angiosperms, a close
i
between the Frankeniaceae and Elatinaceae seems doubtful.
The family
known chemically
is little
(Gibbs, Hegnauer). Several phenolic
acids (delphinidin, ellagic acid, quercetin, cyanidin, kaempferol) have been
reported from Bergia (species not indicated); saponins and alkaloids are absent
from Bergia, while tannins occur in at least two species. Bergia suffruticosa
has been found to lack alkaloids. Elatine appears to be poor in taxonomically
interesting chemicals: E. gratioloides A. Cunn. contains no alkaloids, saponins,
or leucoanthoc\iini
'
i
,
'xa
i
il.apierre)
DC. contains
ellagic acid
but
compounds. The petals of E. americana (Fernald) and E.
minima (pers. obs.) are sometimes pinkish, probably because of anthocyanins.
Gibbs reported druses and raphides to be absent in the family, while Metcalfe
& Chalk noted the occurrence of cluster crystals in the endodermis and pith
of Bergia (species not indicated), and Carlquist recorded druses and solitary
crystals in the parenchyma of B. suffruticosa.
The family is of little economic importance. No species is recorded as being
gathered for use as food or condiments, nor is any reported to be poisonous
=
In
36, is employed in Pakistan
Bergia
suffruticosa.
livestock.
or
humans
to
in folk medicine and in Sudan as a poultice for broken bones.
Several species of Bergia are weeds in rice fields in the Old World, as are
species of Elatine in California, Japan, and Java. The seeds and foliage of
Elatine are eaten by ducks, and the plants are considered to be beneficial because
they consolidate mud and provide cover for small fish. Several species (e.g.,
E. HydropiperL. and E. triandra) are cultivated as "turf- forming" foliage plants
in aquaria. They are reported to be easy to propagate from either cuttings or
lacks other phenolic
The family
is
poorly
known
A
taxonomically.
comprehensive worldwide
revisionary study of Bergia has never been made. The only global monograph
of
the
account
Niedenzu's
(Dumortier).
1870's
in
the
appeared
Elatine
of
Elatinaceae in Die Natiirlichen Pflanzenfamilien is of limited use for the identification of specimens because of its synoptic nature. Most taxonomic inves-
been concerned chiefly
with the description of new taxa. Most workers seem to have been familiar
only with the species represented in their herbaria.
tigation in this family has either involved floristics or
dn,
Families des plantes. 2 vols. 640 pp. Paris.
under the generic name Potamopitys Adanson,
7,
5
M.
Alsines, Alsines,"
i<
\
rLliiia'.t.
i.e.,
li
|
the Caryophyllaceae.]
'
I
Mi.
•
4:
i'.
DO
I
'I
I
,,
i
/w/sMillu
mi
1)
Roxb., Elatine triandra, and E. ambigua.]
Elatinaceae. Hist. PI. 9: 218-221. 1888. [Affinities of the family; Bergia
s and Elatine paludosa (Bell.) Seub. illustrated.]
s
& J.
D. Hooker. Elatinaceae. Gen. PI. 1: 162, 163. 1862.
;sey, C. E. The phylogenetic taxonomy of flowering plants. Ann. Missouri Bot. Gard.
2: 109-164. 1915. [Elatinaceae, 138, placed in Caryophyllales immediately following
vtham, G.,
the Caryophyllaceae.]
JOURNAL OF THE ARNOLD ARBORETUM
474
Bofkovskikh,
Maim
&
[vol.67
Zakharhva. Chromosome numbers
of flowering plants. A. A. Fedorov, ed. (Russian and English prefaces.) 926 pp.
Leningrad. 969. [Bergia and Elatine, 263; most chromosome counts through 964;
B. ammanioides Roth, In = 24; B. capensis L., 2n = 18; 11 sujfruticosa. In = 36;
hexandra. 2n = 72; E. ilvdropiper. In - 40;
triandra. 2h - 40
Brfwbaker, J. L. The distribution and ph\L
.Ui
h
kc of binucleate and
Z., V.
Grif, T.
\,
\
ii
().
1
1
/::.
/•;.
.]
i.
,
trinucleate pollen grains in the angiosperms.
[Elatinaceae,
Am.
1078; discussion. 1076; Elatine
Jour. Bot. 54: 1069-1083. 1967.
K num.
,h
leak- pollen (1
species
examined), while Bergia sheds binu leak- poll(2 species examined). The trinucleate pollen of Elaiim d
n Irom .11 oihi
gu .It
gem
of the Theales and
supports a possible relationship with the Tamaricaceae but not with the Caryophyli,
i
i
i
Cambfssedes, J. Note sur les Elatinees, nouvelle famille des plantes. 7 pp. Paris. 1829.
[Family and generic descriptions; brief discussion of features distinguishing Elatinaceae and Caryophyllaceae and of possible relationship with Hypericaceae.]
Candolfe, A.
Elatinaceae. Prodr. Syst. Nat.
P. de.
390. 1824. [Elatinaceae included
1:
in the Caryophyllaceae.]
Carlquist,
,u
i
i
Wood
S.
m
d
id
and stem anatomy of Bergia
i"iiilu
i
ma
ol
.lliUi
,i
\
Ann. Missouri
fibriform vessel elements.
it
of Elati-
sujfruticosa: relationships
In id-
<
\
i'
in
i
in'
H
i
Ik
'
n
i
I
Bot. Gard. 71: 232-242. 1984. [Photo-
graphs of stem cross sections; wood structure supports relationship with woody
members of the Guttiferae.]
Casper, S. J., & H. D. Krai sch
Pteridophyta und Anthophyta. 2. Teil: Saururaceae
bis Asteraceae. Band 24 in H. En
J. Gi-.ki.ofi-, & H. Hi yniu Susswasserflora von
Mitteleuropa. Pp. 105-944. Stuttgart and New York. 1981. [Pagination continued
from part
(Vol. 23, 1980); Elatinaceae, 614-626; Bergia capensis and ten species
of Elatine; illustrated.]
Cook, C. D. K. Elatinaceae. In: T. G. Tutin et al, eds., Fl. Europaea 2: 295, 296.
i
.,
1
[Bergia capensis
196?
i
weed
in
fields in
ric<
Spain; seven indigenous species of
Elatine and one introduced species (E. ambigua) in Europe.]
Elatinaceae. Pp. 77, 78 in V. H. Hlvwood, ed.. Flowering plants of the world.
New York. 1978.
.
M. Rix, J. Suinfffer, & M. Seitz. Water plants of the world.
vii + 561 pp. The Hague. 1974. [Elatinaceae, 230-232.]
Corner, E. J. H. The seeds of dicotyledons. Vol. 1. x + 31 pp. Cambridge, England,
and New York. 1976. [Elatinaceae, 128.]
B.
,
Gut,
J.
E.
1
Correff, D. S., & H. B. Correll. Aquatic and wetland plants of the southwestern
United States, xvi + 1777 pp. Environmental Protection Agency, Washington,
>"
issi <<1 iii
oliiu.
Si ,ii. (.id
up In
!>'
M Jen;ia
ma. id tin
di.
di a Gao
'ivsncrnni Gra\
chitensis
n
triandra ihe first lour illustrated with plates irom M
o
M. C. Johns idManual of Hi. vascular plants ol l\\\as.
|>P
]
I
<
i
'
'
,
I
.
i
I
)
I
>>
1
|
'»
/
i
•
-&
|
Renner, Texas. 1970. [Elatinaceae. 1066
w
MHu
1067
triandra
Elatiru
'!
1
i
ind
brach)
/
mil Iuj
m
;u
"in ditches, swamps, marshes, and on mud about ponds and on wet banks in southern
i
»
I
.oil
i
i.e. in
in
''ii ill;
'
..
'
/
,
Cronquist, A. An integrated system of classification of flowering
York. 1981. [Theales, including Elatinaceae, 334, 335.]
Davis, G. L. Systematic embryology of the angiosperms.
vii
\
/
;
,i
•
i
plants.
+ 528
,i
,
1262 pp.
pp.
New
New
York.
1966. [Elatinaceae, 227.]
Dumortier,
B.
C
Exaincn eritiqu
Ilimnm
d(
Hull Soc.
Roy. Bot. Belg. 11: 254-
274. 1872. [Taxonomic history oi'Elaiine; origin of the generic name; synopsis of
Imhmi
\
\\
BimlKhdiagiammc
'
1 In
il
575 pp
l.eip/ig
1878. (Reprinted
TUCKER, ELATINACEAE
1986]
1954 by Otto Koeltz.) [Elatinaceae,
Elatine Alsinastrum, E. hexandra E. n
in
ioides.]
Pollen morphology and plant taxonomy. Angiosperms. 539 pp. Stockholm. 1952. (Corrected reprint with addendum [pp. 541-553]. New York. 1971.)
in
grains
pollen
"The
IB;
Meyer,
E.
9
anagalloides
Bergia
159;
[Elatinaceae,
fig.
Erdtman, G.
±
Elatinaceae are
different
in Caryophyllaceae, Frankeniaceae,
from the grains
Ly-
thraceae, Tamaricaceae, etc."]
Fernald, M.
Gray's manual of botany, ed.
L.
+ 1632
lxiv
8.
pp.
New
York. 1950.
[Elatinaceae, 1015, 1016.]
Gibbs,
R. D. Chemotaxonomy of flowering
plants. 4 vols,
xx
+ 2372
pp. Montreal
and
London. 1974. [Elatinaceae, 3: 1839, 1850, 1851.]
Gleason, H. A. New Britton and Brown illustrated flora of the northeastern United
547;
[Elatinaceae,
2:
546,
1952.
York.
New
vols.
3
Canada.
adjacent
and
States
figures of Bergia texana, Elatine triandra var amcricana and var. brachysperma;
taxonomy follows Fassett.]
Godfrey, R. K., & J. W. Wooten.
Aquatic and wetland plants of the southeastern
328-330,
[Elatinaceae,
Georgia.
Athens,
+
933
x
pp.
Dicotyledons,
United States.
North
western
from
reported
is
amcricana
var.
triandra
Elatine
no illustrations;
texana
Bergia
Missouri;
and
Tennessee,
Mississippi.
Georgia,
Carolina, northern
from
Arkansas, Texas, Washington, and California.]
Illinois to
15:
Fl.
URSS
eds.,
Bobrov,
E.
&
B.
i
Elatinaceae.
In:
Gorshkova, S. G.
by
translation
(English
s
193-203.
1974
15:
s
R.
Ki.
(in
259-271. 1949
AlsinasE.
species);
(seven
Elatine
species),
(two
[Bergia
N. Landau. Jerusalem).
i
•
I
.
1
truntand
pi
triandra illustrated
I
"'
i
,
\
Vol.
illustrate
1. 230 pp. 100 pis.
borcali-orienUilis
americae
Gray, A. Genera
"£.
ameri(misidentified
as
minima
Elamu
217-220;
[Elatinaceae,
Boston. 1848.
excellent
descriptions,
pi
good
961;
tc
una)
/
(as
texana
Bergia
cana"), pi. 95;
florae
;
family.]
5 vols. Basel
lomie der Pflanzen.
.
Walia
&
and
Stuttgart. 1969. [Ela-
Pp. 647-696 in B. M. Johri, ed., Em[Elatinaceae, 661; discussion of work of
Kapil.]
Hitchcock, C.
L.,
&
A.
Cronqi
Vascular plants of the Pacific Northwest. Part
ust.
3:
Saxifragaceae'to Ericaceae. 614 pp. Seattle. 1961. [Elatinaceae, 434-437, illustraunerkana
- lath
ind
xa
Bergia
tc
of
]
illustrations
detailed
tions, 441;
1972.
Taipei.
pis.
vii
175
+
297
Frontisp.
pp.
Taiwan.
of
flora
Pollen
Huang, T.-C.
1
1
\
described,
triandra
and
lain
1
Blanco
w
serrata
Bergia
62
pi
106
[Elatinaceae,
illustrated; best published photographs of pollen of this family.]
Hutchinson, J. The families of flowering plants. Vol. 1. Dicotyledons, x + 510 pp.
iud
Hu
h
hn
4
[Caryoph\llal
London. 1959.
Unm
Jussmu, A. L.de. Genera plantarum
l
!
|
h
i
Elatine, 333; included in Caryophyllaceae.]
Knuth P. Handbook of flower pollin m<<n
t
iv
n;-l
h
+ 526
h
i
>
pp. Zurich. 1791. [Bergia,
lan<
i
b>
J.
R.
Ainsworth
pp. Oxford. 1909. [E. hexandra, 203; "authis species,
of
flowers
reddish-white
small
phi
n
the
ia
x
II
p-lhnati
s<
ton.diu
three
stigthe
upon
directly
pollen
shedding
and
introrsely.
dehiscing
the anthers
Davis.) Vol.
2.
Frontisp.
>
+
vii
+ 703
.
.
et analydescriptive
botanique
general
de
Trade
868.
Decaisne.
Le Maout, E., & J.
seeds
and
flowers,
habit,
436;
[Elatinaceae,
435,
1868.
Pans.
+
746 pp.
tique. viii
Hydropiper illustrated.]
of£. hexandra, E. octandra, and
London
viii
1
608
Vol.
+
of
seedlings.
pp.
knowledge
our
to
Lubbock, J. A contribution
1
/•-'.
.
and
New
York. 1892. [Elatinaceae, 230, 231.]
JOURNAL OF THE ARNOLD ARBORETUM
476
Mason, H.
A
L.
IMS-
Vlljeks
[]
|
i
sperma,
|„
|
E ami
E ohovaiu
(arnica
|«.
.
&
11,1,1
1!
(1
Mason
Mason ind
ell)
i
Pp. 334. 33
S
>
,
i
l
J
ilensis
Mason
all
and Los
a!lm
{ll
(,
hrachy
I
iliiislralcd.j
miok. Hngler's Syllabus der Pflan-
<
oniparahve ana
(
I\
i'
'
i
'
'
Mi
,„
t
1
hclcniinini
II
//;
s
/,',,,,,
I
/
/
pp. Berkeley
Berlin. 1964.
2.
DnnxKixs
I
<>•
'
'
„.;
lis
/enfam.lien. ed. 12. Vol.
P.,
U
,,
,
i
Melchior, H. Elatinaceae.
Mei.ikian, A.
+ 878
of the marshes of California. vdi-[x]
flora
[vol. 67
and palynological study
...I
n
in
(
nai
il
ii
)Piol
i
lim
;
Armian. 30(11): 44-49. 1977. [Investigation of Elatine Usinastnim, Hernia amina/aouh
B odouita Edgew., B texana M in in
ji
,o>
ol, m
,«h n
photomicrographs and buel h
up inn oftl pollen grains.]
MircAiFr. ('. R.. & L. ( mmk
-,<-|
-.,...,
s
m,....!.
]<;sii
...
I)
I.
Moi.au, U. Elatinai.ic ///
II
in
A I' si \i ki eds., Fl. Ecuador 20: 19-23.
I.
1
.
,
i
()
•
1983.
Munz,
A
A.
,
,„
[£<>/;<,'/</
P.
<
,i
i
,
and
.,
illustrated.]
California flora. 1593 pp. Berkeley. 1954. (Elatinaceae, 271-273; E.
cahfornica illustrated.]
N'i:i>i\/r.
Elatinaceae.
'.
I
///;
Em.iik
A.
K I'lewn,
<\
Nat. Pflanzenfam. ed.
21:
2.
270-276. 1925.
Radford, A. E„ H.
I"
IIS3pp
&C.
E. Aiiles,
R.
Bo a
ortlH
Manual
.
ihevascnlai Hon
ol
!%8
ol ih,
irolina;
'
lalmaa
singl.
-ecu
Elatine triandra, recorded from the mountains of North ( arolina (Jackson Co.).]
Rfndle, A. B. Classih
m of the flowering
mis Vol. 2. Dicotyledons. 640 pp.
Cambridge, England. 1952 [Pan,
ilnmi,.,
(P
lollowing the FranI.
pel Hill
I
nolina
'
[1
i
i
I
,1
i
H.
Rii.ey,
P.
Familu
if
:i
I
flowering plants
outhern Africa,
ol
+ 269
xviii
pp. 144 color
photographs. Lexington, Kentucky. 1963. [Elatinaceae, 140, 141.]
Russell, G. E.G. Taxonomic bibliography ol "\ aseula, aquatic plants in southern Africa.
'ill iiol
,-,,
o,
\|,
K(i
IS"
,, ,„,.
,„,
\l\
l.mu.ui.n
Sculthorpe, C. D. The biology of aquatic vascular plants, xviii +- 610 pp. London.
1967. [Numerous references to Elaiuw and Bngia: I
ml
like
aquatics.
•
I
«
,
|
.
|
i
|
mam
has different growth forms
Stevfrmark,
J.
A.
in
and out of
w.iu
Flora of Missouri, lxxxiii
inaad.a 68
(/
i
fit*
1
5)
]
1725 pp. Ames, Iowa. 1962. [Elatine
t-
th species very
Thoknf,
\ plnlo
R. F.
',en,
tie
,
lassiiicalio
the
ol
i
1976. [Thcalcs: suborder Hypericinac: Elatinaceae, 57, 58.
Jour. Bot. 3; 8s 107. ls>X3.]
106.
Walia,
K.,
&
R. N. K\i'ii
.
I
mbu
oIolm ol
•'
i,
n,<
'
,
35See also Nordic
\ngiosp< rmae. Evol. Biol. 9:
i,,n
,th
some comments on
the systematic position of the Frankeniaceae. Bot. Not. 118: 412-429. 1965. [Elatlo
an
i, Li
n
m.i
o
h
n
bitegmic ovules, monosporic embryo sacs,
1
^d
t
,
,
i
i
I
i
,
i
i
I
|
;
Wi
,
'
formation commences at the chalazal end;
keniaceae in the Parietales near the Elatinacea
ttsti in, R. R. von. Handbuch der s
Leipzig and Vienna. I'M
n in
i
il
i
hara<
It
i
,
ni/l
s
[Paneiale
Elatinaceae
'"<
4,
following Frankenia
I
,
TUCKER, ELATINACEAE
Plants glandular pubescent throughout; flowers 5-merous; sepals acute, with a conspicBergia.
1
uous, thickened midrib; capsules ovoid
.
Plants glabrous; flowers 2-4-merous; sepals obtuse, without a visible midrib; capsules
2. Elatine.
globose or depressed globose
1.
Bergia Linnaeus, Mant. PL
2:
152. 1771.
Annual [or perennial], herbaceous [or suffrutescent], simple to much-branched
procumbent to ascendent plants of moist, disturbed soils; often occurring on
sand bars along rivers. Roots fibrous, much branched from a conspicuous
leaves.
lower
of
the
axils
the
in
formed
usually
roots
adventitious
taproot;
Stems herbaceous but woody and thickened at base, glandular pubescent
throughout. Leaves decussate, glandular pubescent on both surfaces [or glaFlowers
pubescent.
glandular
scarious,
stipules
serrate;
margins
the
brous],
mucronate,
with a thickened midvein and scarious margins, glandular pubescent throughsolitary or in dichasia in the axils of the leaves. Sepals 5, free, acute,
out. Petals 5, oblong,
membranaceous, glabrous, whitish. Stamens
5 [or 10];
anthers ellipsoid; pollen tricolpate, subprolate to spheroidal, sexine reticulate
6]-locular
[or
ovoid,
Ovary
5
when
shed.
binucleate
reticulate-polybrochate,
to
[the partitions not reaching the summit in some Asian species], each locule
with numerous ovules; stigmas 5; styles 5, very short. Seeds oblong, slightly
curved, brown, obscurely reticulate [smooth]. Base chromosome number 6.
1730-1790,
Bergtus,
Peter
Jonas
for
(Named
L.
capensis
B.
species:
Type
Swedish botanist and student of Linnaeus.)
species
Three
tropics.
World
of
the
Old
primarily
25
species,
about
of
A genus
''
Camb. in Brazil; B. capensis,
World:
New
Ben
occur in the
2n= 18, native to Africa and southern Asia, collected as an adventive on the
Pacific coast of South America (Molau); and B. texana (Hooker) Seub., ranging
from Illinois, Missouri, Arkansas (Desha County), and Louisiana (Bossier, Red
River, St. Mary, and Grant parishes), westward to northern Mexico, southern
'•
California,
and eastern Washington.
The center of greatest diversity in the genus is in eastern and southern Africa,
where some 20 species occur. By contrast, there are only five species in southern
which ranges from
capensi
Asia and two in Malesia and Australia.
southern Africa to India and Indonesia, is the most widely distributed species
Spain
fields
in
in
rice
weed
adventive
an
recorded
as
is
also
It
genus.
in the
;
-
and Portugal.
Niedenzu divided the genus
sect. Bergia (seel.
into
two
sections.
He
placed Bergia texana in
Med/.), in which the flowers are borne in
axillary dichasia. Species of sect. Monanthae Niedz. are characterized by
'
solitary axillary flowers.
Apparently nothing
About half the
is
known about
the pollination biology of any species of
species of Bergia are aquatic; the remainder are plants of
JOURNAL OF THE ARNOLD ARBORETUM
478
moist
[vol.67
According to D'Almeida, B. capensis has dimorphic roots. The
plumose water roots lack root hairs but frequently have chloroplasts in the
soils.
cortex and thus supplement the leaves as assimilatory organs. The stout whitish
roots that anchor the plant in the muddy bottom of the pond or pool bear very
few
lateral roots
but are almost completely covered by root hairs.
Under family references see Backer, Baili.on, Bi-ntiiam & Hooker, Bessey,
Bolkovskikh el ai. Brhwbakik, Cxmiu ssldi s. Di Canixilli:. Cari quist, Cook (1968,
1978), Corner, Corri
Cork:
& (okhi
& Johnsion, ( konouist, Davis, Eichler, Erdtman, Gibus. Gi -vson. Gorsc iikova. Gray. Hi rr. Hue ikock & Cronquist,
Huang, Hutchinson, Li: Maoim & Decainne, Lubihx k. Mason, Mei.ikian & Dildarian, Metcalfe & Chalk. Molau, Munz. Niepen/u. Rindee, Riley, Russell,
Scuithorpe, Steyermark, Takhtajan. Thokne, and Walia & Kapil.
i
i
i
i
i
.
i
i
D'AlmeidaJ.F. R. A contribution to the siikb of'ihi biology and physiological anatomy
of Indian marsh and aquatic plants. Part II. Jour. Bombay Nat. Hist. Soc. 43: 9296. pis. 1-3. 1941. [Habit, ecology, and anatomy of Bergia capensis; 20 figures.]
Daihan, A. S. R., & D. Singh. Embryology and seed-development in Bergia 1 Jour
.
Indian Bot. Soc. 50: 362-370. 1971.
&
Development and
•
structure of female
ndorata Edgew. Proc. 57th Indian
Ghaeoor, A..&S
!
1
tin
I
,
<
Sci.
Congr. 3(4): 254, 255. 1970.*
r,
'I
<\,
,
gametophyte and seed of Bergia
1
,
kisian 19: 1-5. 1972. [Descriptions,
keys, illustrations of three species of Bergia.]
Hooker, W.
Bergia texana.
J.
Kajale, L. B.
A
278. 1840. [Original description (as
Ic. PI. 3: pi.
contribution to
iln'
fi
hi
tor}
oi
immanioides Jour. Indian
••
Be)
Merimea
Bot. Soc. 18: 157-167. 1939.
Ragiiavan, T.
capensis
Ramayya,
I
&
S.,
inn
&
V. K. Srinivasan.
lorn
M. !v
Ituli
n
I!
.o.
;i
A
contribution to the
I"
S
,
i')\
I
life
history of Bergia
^40
rhe morphology of the shaggy appendages. II. Elatinaceae. Jour. Indian Bot. Soc. 54: 110-115. 1975 [Multiserial capitate glandular
trichomes in
/<
Ro\b
Thieket,J. W. Additions to the
n ilo.
uii?
o
_ „
966. [Bergia texana
N.,
'
••
.ii
,i
-.
s
-
]
I
Yousif,
G,
in the
G. M. Iskander,
Sudan
llo. a
iu
&
<
.
E. B. Eisa.
mpiaS4(2)
(
!
Investigation of the alkaloidal
M
Hi
!
i.
\li
,
components
<l>wu -o.sa. used in folk
medicine, contains no detectable alkaloids.]
2.
Elatine Linnaeus, Sp.
PI. 1:
367. 1753; Gen. PL ed.
5.
172. 1754.
Small, aquatic or emergent, herbaceous annuals or short-lived perennials of
marshes, streambanks, shores of lakes and ponds, mud flats, pools, ditches,
and
Roots slender, soft, the exposed portions sometimes with chloroplasts in the cortical cells. Stems soft, chlorophyllous, with 5air chambers
visible in cross section; stems upright when growing underwater, more or less
procumbent when growing on wet soil or mud. Leaves opposite, sessile or with
short petioles, blades narrowly to broadly elliptic to nearly orbiculate, onerice fields.
1
1
fourth to three-fourths as long as wide, entire or essentially so (with hydathodes
on the margins at the ends of the veins) the apices rounded, the bases cuneate
to somewhat rounded. Flowers solitary in the axils of the upper leaves, [2 or]
TUCKER, ELATINACEAE
1986]
479
membranaceous, very pale green, inconspicuous. Petals
the same number as sepals, membranaceous, pale greenish white, about as long
as the sepals [small floral nectaries present in some species]. Stamens [2 or]
3 [or 4]-merous. Sepals
about half as long as to equaling the petals; anthers tetrasporangiate (sometimes bi- or trisporangiate in cleistogamous flowers), broadly
ovoid, the connective apex subacute, prolonged slightly beyond the anther
3 [-8]; filaments
locules; pollen tricolporate, spheroidal to subprolate, sexine granulate to reticulate, trinucleate
when
shed. Ovaries broadly ovoid, [2 or] 3 [or 4]-locular, the
partitions thin, fragile; placentation basal [axile]; styles 3; stigmas terminal,
appressed to the ovary. Capsules subglobose or depressed ovoid, the walls thin,
membranaceous, delicate, the seeds more or less visible within. Seeds cylin-
narrowly to broadly ellipsoid, the surface
brown to yellowish brown, reticulate with a network of fine ridges forming
hexagons [ovals]. Base chromosome number 9. Lectotype species: E. Hydropiper L.; see Britton & Brown, Illus. Fl. No. U. S. & Canada, ed. 2. 2: 538.
drical, straight or slightly curved,
1913; also see Hitchcock
& Green.
name employed by
{FJatme, a Greek plant
Dioscorides and Tournefort and adopted by Linnaeus [Crit. Bot. 103. 1737;
Philos. Bot. 144, 174. 1751]; also see Dumortier, Gray.)-WATERwoRT, pigmy
A genus of about 25
species, interruptedly
cosmopolitan in distribution, with
on all continents except Antarctica. Ten species are native
in
seven
species
are
five
to
There
Eurasia.
12
to
and
about
America
North
to
South America, mostly in temperate and Andean regions. Three primarily
European species occur in North Africa; none apparently grows in the central
part of the continent, while two are reported from Zimbabwe and Namibia
(Riley). Two species occur in India and Malesia; one, Elatine gratioloides
Bentham, is found in Australia, New Zealand, and Fiji.
Two subgenera and three sections were named by Seubert, whose classification was followed by Niedenzu in Die Naturlichen Pflanzenfamilien. Subgenus Potamopitys (Adanson) Seub., containing only Elatine Alsinastrum of
Europe and North Africa, is characterized by having whorled leaves. The
remaining species, all of which have opposite leaves, comprise subg. Elatine
(subg. Hydropiper Moesz). Subgenus Elatine contains two sections. Section
Elatine (sect. Elatinella Seub.), in which the flowers have six to eight stamens
in two whorls, includes about eight species of Eurasia, California (E. heterandra), and South America (E. ecuadoriensis). The remaining species, which
have two or three stamens in one whorl, comprise sect. Crypta (Nutt.) Seub.
and occupy nearly the total range of the genus. All North American species
species occurring
(except E. heterandra, q.v.) are included in this section. Elatine heterandra
may have either three or six stamens per flower (Mason), thus shedding doubt
of stamen number in classification.
4
species occur in the Southeast. Elatine americana
on the
reliability
Two
4
The taxonomy used
specimens
,
1
r
,
,i,
(at \,f< ni
,,guisluil)k1
1
o.
1
1
on
hei
<
loll
rnaUiM^I
I
cAcaiiu
in
(i
d
ilu
mn
li.i'.i
il
1
1
m.l
*
1941)
)>h<n
ii
)i
1
1
urn
is
known from
col-
\n examination of numerous herbarium
ih.u
/
////;/;
I.. sin
1
/
n.l
n
.1
n
",1111,1
1
ano
/
uiiu
,1,
ami
on) treated these species
JOURNAL OF THE ARNOLD ARBORETUM
480
[vol. 67
North Carolina, and Vermillion Parish, Louisiana. It
ranges northward to Newfoundland and southeastern Manitoba. It is also common in Australia and New Zealand (Moore & Betche, Cheeseman, Good).
More recently, Aston treated these Southern Hemisphere populations as a
species, E. gratioloides, but her description and illustration seem indistinguishable from those of E. americana.
The other southeastern species, Elaime hrachysperma, occurs from Georgia
westward to California. Specimens have been seen from Georgia (Hancock and
Oglethorpe counties), Alabama (Pern
ounty) and Louisiana (Cameron and
lections in Jackson Co.,
Lafayette parishes).
Two additional species occur in northeastern North America. Elatine minima has a wide range, from Labrador to the Northwest Territories, southward
to Virginia
and
Illinois.
Elatine triandra, a Eurasian and western North
Amer-
and Brooklyn, New
York; in both localiti s h
believed to be an introduction from Europe. Five
species— two endemic to California— occur in western North America.
Plants of Elatine grow as submersed or emergent plants in shallow fresh
[brackish or alkaline] pools, lakes, ponds, and ditches. They often occur in
iii
drained or in natural pools that dry out.
ican species, has been collected in Skowhegan, Maine,
i
,
.!,.,
.1,
I
Many species show some adaptation
to fluctuating water levels in
having plants
with different growth forms under water and on land. The most striking example
of this dimorphism occurs in the European E. Alsinastrum, the only species
with whorled leaves. The upper, emergent portion of the stem bears whorls of
leaves with ovate blades 1-2
cm
submersed lower stem has
leaves divided into four capillary segments, thus giving the appearance of 12
leaves per node. In the remaining species terrestrial and aquatic forms are less
different. In E am>
wan
vspern
submersed plants have longer
internodes and longer, narrower leaf blades and are darker green than littoral
plants (Bicknell, Sculthorpe; illustrations in Fassett and Kupper & Gams).
Knowledge of the pollination biology of Elatine is incomplete. Cleistogamous
underwater flowers are present in many species (Duncan recorded them in
populations of E. americana in Georgia). Chasmogamous flowers have small
nectaries, but no report of insi
iu»i
h,
been found. Self-pollination in
E. hexandra, In = 72, is effected as the filaments elongate, bringing the anthers
long, while the
i
i
i
-
i
into contact with the stigmas (Hutchinson, 1955; Knuth). Self-pollination has
been observed to occur
same manner in plants of E. minima collected
and grown indoors at the New York State Museum (collection from Stonington,
Connecticut, G. C. & J. R. Dicker 3217 [nys]). In the cleistogamous flowers
of E. triandra, In = 40, and E. hexandra the anthers are brought into contact
with the stigmas as the filaments elongate. The pollen grains germinate in situ,
and the tubes grow through the anther wall into the stigma (Frisendahl).
Under family
Bolkeiovskikh
Cook
the
in
Adanson, Backer. Baillon, Bentham & Hooker,
Brewraker, Ca.mhensedes, Di Candoiii, Cook (1968, 1978),
references see
el at,
Corner. C'orrii & Corri
Corri
& Joiinsion. Cronquist, Davis,
DUMORTIER, ElCHI.ER, ErDIMAN, FlRNAIEJ, GllSBS, Gl.EASON, GODIREY & WOOTEN,
et a!.,
i
i
i
.
i
i
TUCKER, ELATINACEAE
Water
Arber, A.
436 pp. Cambridge, England. 1920. [Elatine, 245;
he.xaiu.lru show ing the circle of root hairs that surrounds the
plants, xvi
germinating seed of
E.
t-
minute radicle, jfe 158.]
Aston, H. I. Aquati
3
"
76 description illustration of
i>ratu>h>idcs lien t ham
7
(/
74-
[Elatinaccae
amencana
vai
Argi itinj
D
iiistrali
ensis).]
Bactgalupo, N. M. Observaciones sobre el genero / latine&n
16: 106-1 15. 1970. [Revision of the Argentinu] pecies
la
•id
,,,,'
/
irwiniana
a and E. opposita;
illustrated.]
+ 298
habitat data, iv
Bicknell,
The
E. P.
N
pp.
'
amlin
i
V.i
:
xpcr
1977. [Elatine
Sta., Raleigh.
and (lowering plants
ferns
Club 40: 605-624. 1913. [Elatinaceae: E. an
mersed and terrestrial growth forms based o
Cajander, V.-R., & R. Ihantol a. Mercury in some higher aquatic plants and plankton
mthern Finland \nn. Bot. Fenn. 21:
in the estuary of the River Kokemaenjoki.
thandra I
in
151-156. 1984. [Highest concentrations ol mercuiy del
i
.'
-
m
n
dry weight.]
Effects of fish nests on pattern and zonation of
Carpenter, S. R., & N. J. McCri \m
submersed macrophytes in a softwater lake. Aquatic Bot. 22: 21-32. 1985. [Elatine
"h/i
l!vclr<'/'i["
t
)
nllion,
i
i
.
colonizes sunfish nests in Michigan and Wisconsin.]
ed 2 W. R. B. Oliver, ed. xliv
Cheeseman, T. F Manual ol thi
s
Bentham in New
,.
ton 19?
1163 pp Wei
minima
.
i
\ahnd
De Wit, H.
m
\
C. D.
London. 1973
i<\
\
)
\n
Aquarium
d
tin
ia\on
<n<u-
i
i-
plants. (English translation
I'H
197
latint
[1
at-
1/
/
„„„
,
E
yatioloides.]
by
J.
„
A. Schurman.) 220 pp.
u
>
i>
m
<
<
n<
Duncan, W. H. New /tj//w(Elatinaci ac) populations in the southeastern United States.
riandra in gi riite outcrop pools in the Georgia
Rhodora 66: 47-53. 1964 [1
Piedmont; comments on difficulties in assigning these plants to either E. amencana
/
or E. brachysperma sensu Fernald.]
Eames, A. J., & L. H. Ma< Danii s. An introduction to plant anatomy, ed. 2. xviii +
427 pp. New York. 1947. [Cross section of stem of Elatine (species not indicated).
i
fig-
183.}
Fassett, N. C. Notes from the herbarium of the University of Wisconsin -XVII.
Elatine and other aquatics. Rhodora 41: 367-377. 1939. [/':. brachysperma and E.
The genus Elatine in eastern North America. Rhodora 19: 10-15. 1917.
>aiuha. specimen citations.]
>,n ,i.,m
amencana
94 [Defense of specific
Elatine amencana and E. riandra. Ibid. 43: 208-2
Fernald, M.
[E.
.
L.
•'
i
t
1
1
.
1
1
.
n placentation and leaf shape from the primarily
statusofi am icana iifferenci
Eurasian E. t riandra.]
Frisendahl, A. Uber die Entwicklung chasmo- und kleistogamer Bluten bei der Gattung
Elatine. Acta Horn Gothob. 3: 99-142, 192/. [Anatomical investigation of E. hex,
,io,i.
Gauthier,
and
R.,
/
n andra
& M
man
K\\\u
Univ. Montreal 64
L
uion:
cruel
Discu
'9
cana, E. tnandra, and E.
Godwin, H. The
i>.
illustt
minima
in
|
lans
,
1
kiebn
on, keys, distribution
onii
Insl
Bo
maps of E. amen-
North America.]
history of the British flora, ed.
2.
x 9
541 pp. Cambridge, England.
JOURNAL OF THE ARNOLD ARBORETUM
482
1975. [Elatine,
141.
142;
//.
hcxamira and
deposits at several localities in the British
Goon.
Hydropipcr found
/.'.
Isles.]
The geography of the flowering plants, ed. 3. xvi + 518 p
England. 1964. [Elatine. 88. 230: E. amencana in North America and disjunct in
Australia and New Zealand.]
Hardy, A. Monographic des Elatine de la More beige. Bull. Soc. Bot. Belg. 10: 1 73—
194. 1871. [Taxonomic history of the genus; descriptions of the eight species atR. D.
tributed to Belgium.]
Heusser, C.
Pollen and spores of Chile;
J.
nospermae,andAngiospermae.
ne chilensis, 33, 34, pi. 27.]
Hitchcock, A. S., & M. I Gri
gamae (1753-1754).
i
xiii
modern
167 pp. 60
i
pis.
Tucson. Arizona. 1971. [Elati-
Standard-species of Linnaean genera of Phanero-
n.
Pp. 110-199 in
Ramsbottom
J.
Proposals by British
el at.,
London. 1929. [Elatine 151;
Hydropipei th< type species.]
Hunziker, A. T. Sobre una nueva hidrofita argentina: Elatine Lorentziana nov.
botanists.
'
Spanish; English abstract.) Lorentziana
J.
1:
5-10.
British wild flowers. 2 vols. 491 pp.
sp. (In
1970. [Description, illustration,
new species closely related to the eastern North American
discussion of a
Hutchinson,
Gym-
types of the Pteridophyta,
minima.
E.
]
Harmondsworth, England. 1955.
hexandra, 2: 374, illustrated; self-pollination described.]
Katz, N. J., S. V. Katz, & M. G. Kipiani. Atlas and keys of fruits and seeds occurring
in the Quaternary deposits of the U.S.S.R. (In Russian; English and Russian title
pages.) 365 pp. Moscow. 1965. [Elatine. 2\l, Jigs. 62.S-62.I3: seeds of/7 Alsinastrum, E. hexandra. E. Hvdiopiper.
orthospcrmu, E. irtandra recorded.]
Kerner von Marii.aun, A. Natural history of plants. (English translation by F. W.
Oliver et al.) 2 vols. Glasgow. 1904. [Elatine livdropiper, 1: 868; seeds of this
species are common in mud carried on the feet of birds. This appears to be the
[E.
E
ourci
ol
l
lan in
in
i
ted le
-.
i
i
persed by waterfowl.]
Keeper, W., & H. Gams.
Flat.naceae.
hoi
ite
I
///;
G.
Hon,
(e.s
\em
u.)
ed., lllus. Fl.
that
.'
Ian u
i
lis-
Mittel-Europa 5(1):
535-544. 1925. [Aquatic and terrestrial form oi se era] spe< ies illustrated.]
Lemesle, R. Embryogenie des Elatinacees. Developpement de l'embryon chez YElatine
Alsinastntm L. Compt. Rend. Acad. Sci. Paris 188: 1569, 1570. 1929.
Lohammar, G. The northern limit of
tm
Sv. Hoi
idsskr 67: 306, 307.
1973. [77. triandra northward to 66°42'N latitude m S\ved< n and / liydro/apei to
67°58'N in Finland.]
Love, D., & J. P. Bernard. Flora and vegetation of the Otterburne area, Manitoba,
,
/:.'/
'
i.i'l
7,i
S'
Lid-
h
^s
In = 36.]
Macbride, J. F. Elatinaceae.
Hist. Bot. 13(4): 3, 4.
Maheshwari,
<>a
1
io-461
M
19V)
hmmihunM
[.
u bridi
ouut
/
Ian,,
memaaa
Peru. Publ. Field Mus. Nat.
1941. [Elatine peruviana. E. triandra var. andina Fassett.]
In:
J.
i
.
.
eel.,
Fl.
The angiosperm embryo sac. Bot. Rev. 14: 1-56. 1948. [Elatine Hyl"l
)<<
aiunl. ol oo m
no ol bei rant 16-nucleate embryo sacs
P.
i
,
<
formed from fusion of two normally organized, 8-nucleate sacs.]
Mason, H. L. New species of/ latin m aiil inia Madrono 13: 239, 240. 1956. [E.
gracilis and E. heterandra, spp. nov.]
Moore, C, & E. Betche. Handbook of the flora of New South Wales, xxix + 852 pp.
Sydney. 1893. [Flatnue ic
.1
amencana recorded from southeastern Aus<
)Ri,
C.
Phytosociological studies on the
with special reference to
weed community of the paddy
field
of Japan
See Hiroshima Univ. Bot. 19: 299319. 1985. [Elatine triandra var. pedicellata an important weed of nee fields on
its
spring phase.
.lour.
Hokkaido, Japan.]
iller, F. Untersuchungen iiber die Struktur cinigcr Aiten
on Elatine. Flora (Regensburg) 60: 481-496, 519-526. 1877. [Classical anatomical study of vasculature
\
TUCKER, ELATINACEAE
1986]
483
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,
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[Infraspccific variation in seed production; effects
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.
62°N
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\
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•
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,