On a collection of shallow-water hydroids (Cnidaria: Hydrozoa) from Guadeloupe and Les Saintes, French Lesser Antilles
Author
Galea, Horia R.
text
Zootaxa
2008
1878
1
54
journal article
10.5281/zenodo.184149
086e0d63-8af0-4ad1-8884-03fa56b5ea98
1175-5326
184149
Dynamena disticha
(
Bosc, 1802
)
(fig. 5J–N)
Sertularia disticha
Bosc, 1802
: 101
, pl. 29 fig. 2.
Dynamena disticha
—
Calder, 1991d
: 93
, fig. 50.—
Migotto, 1996
: 62
, fig. 12A–E.—
Medel & Vervoort, 1998
: 25
.—
Peña Cantero & García Carrascosa, 2002
: 121
, fig. 23C–E.
Dynamena cornicina
—
Leloup, 1935
: 39
, figs 22–23.—
Calder, 1983
: 9
, figs 1–2.—Hirohito, 1995: 167, fig. 54.
Material examined
.
Stn. 1
:
19.01.2008
—numerous fertile colonies,
6–8 mm
high, on
Thalassia testudinum
;
25.01.2008
—numerous fertile stems,
5–7 mm
high, on
T. testudinum
(
MHNG
INVE
60980);
18.03.2008
— several fertile colonies,
ca
.
8 mm
high, on
T. testudinum
;
20.03.2008
—several fertile colonies,
ca
.
8 mm
high, on
T. testudinum
;
21.03.2008
—several fertile colonies, up to
8 mm
high, on
T. testudinum
.
Stn. 2
:
22.01.2008
—several fertile colonies,
2–4 mm
high, on sponge and algae;
26.01.2008
—a few sterile colonies,
2–4 mm
high, on algae and rock.
Stn. 3
:
26.01.2008
—numerous sterile stems,
2–4 mm
high, on algae;
01.04.2008
— numerous sterile colonies, up to
6 mm
high, on concretions and algae.
Stn. 4
:
22.03.2008
—one sterile colony,
ca
.
7 mm
high, on ascidian.
Stn. 6
:
23.03.2008
—a sterile colony,
ca
.
7 mm
high, on
Halimeda
sp.;
28.03.2008
—a sterile colony,
ca
.
7 mm
high, on
T. testudinum
.
Stn. 7
:
25.03.2008
—several sterile colonies, up to
7 mm
high, on various algae, a sponge, and concretions;
27.03.2008
—one sterile colony,
ca
.
8 mm
high, on bivalve shell.
Type
locality
. Atlantic Ocean, no exact locality given.
Remarks
. The material originating from calm waters has long stem internodes; they are comparatively shorter in specimens from agitated waters.
The gonothecae of
D. disticha
have been described either occurring on the stolon (
Calder 1991d
) or arising from lower stem internodes (
Medel & Vervoort 1998
), or both (Hirohito 1995). In the present specimens, the gonothecae are mainly borne on the stolon but, in some stems, peculiar gonothecae arise from the hydrothecal openings. These gonothecae did not retain any specific feature of the common
type
: they are sac-shaped, of variable length and width, with smooth to slightly undulated walls, but not ridges; the apical end is rounded and no aperture could be observed (see fig. 5M–N). The gonothecal content is a homogenous mass of tissue (male gonothecae?).
Distribution
. Circumglobal in tropical, subtropical and temperate waters (
Peña Cantero & García Carrascosa 2002
). The Caribbean records are summarized by
Calder & Kirkendale (2005)
.