The non-Siphonophoran Hydrozoa (Cnidaria) of Salento, Italy with notes on their life-cycles: an illustrated guide
Author
Gravili, Cinzia
Author
Vito, Doris De
Author
Camillo, Cristina Gioia Di
Author
Martell, Luis
Author
Piraino, Stefano
Author
Boero, Ferdinando
text
Zootaxa
2015
3908
1
1
187
journal article
42365
10.11646/zootaxa.3908.1.1
6f1d1977-6b97-4789-828c-76ed250cf1ae
1175-5326
242729
D6AD2B49-170B-4D9C-84AA-DBE0FEEAD8BE
Sertularella gayi
(Lamouroux, 1821)
Fig. 94
A–C
See Medel & Vervoort (1998) for a complete synonymy.
FIGURE 94.
Sertularella gayi
:
A
, general view of a colony;
B
, detail of hydrocladia;
C
, gonotheca and hydrotheca (redrawn and modified after Medel
et al
. 1991 by C.G. Di Camillo). Scale bars: A, 5.0 cm; B, C, 1 mm.
Material examined.
HCUS-S 101 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula).
Description
(based on our own observations; Gili 1986; Ramil & Vervoort 1992; Ramil
et al.
1992):
Hydroid.
Hydrorhiza strong, radially ramified; colonies erect, pinnate, well developed, dioecious; hydrocaulus polysiphonic, up to ca
160 mm
, secondary branches sometimes present, internodes thecate, separated by oblique nodes alternatively directed to the left and the right; hydrothecae present in the monosiphonic parts of the hydrocaulus and hydrocladia; lateral, alternate, urn-shaped, tubular, swollen basally and slightly narrower distally, usually with the margin tilted outwards, in abcauline direction, aprox. 1/2 of the adcauline wall adnate to the internode, old hydrothecae with many times renovations, with thickened abcauline wall, adcauline wall often with transverse undulations, more or less pronounced, rim of hydrotheca with 4 equal marginal cusps, hydrothecal operculum of 4 triangular flaps attached in rounded embayments between marginal cusps. Gonothecae on both axis and side-branches, just below hydrothecae, elongated, ovoid, with distal half annulated, aperture circular, usually flanked by 2 broad cusps, typically one larger than the other, 3–4 cusps may occur; acrocyst external to female gonothecae.
Cnidome.
Microbasic mastigophores.
Habitat
type
.
Frequent in fine sand grounds, recorded from subtidal al least to edge of continental shelf, from
10 m
to at least
1200 m
(
Medel
et al.
1991
; Ramil & Vervoort 1992).
Substrate.
Shells of Mollusca, Tunicata, Gorgonacea and other, on tubes of polychaetes, basally with
Opercularella panicula
, algae, concretions.
Seasonality.
January–October (for a review see Bouillon
et al
. 2004); April, May, August–December (De Vito 2006; this study) in Salento waters.
Reproductive period.
January, May, September (Bouillon
et al
. 2004).
Distribution.
Eastern Atlantic, Mediterranean (
Medel & López-González 1996
; Medel & Vervoort 1998; Bouillon
et al.
2004;
Gravili
et al
. 2008a
).
Records in Salento.
Rare at Otranto (De Vito 2006; Gravili 2006;
Gravili
et al
. 2008a
; this study).
Remarks.
The regular and ramified, pinnate structure of the colony may at times, by the development of polysiphonic branches, become irregular (for more details see Ramil & Vervoort 1992).
References.
Picard (1956
,
1958a
), García-Corrales
et al.
(1980), Gili (1986),
Medel
et al.
(1991)
, Ramil & Vervoort (1992), Ramil
et al.
(1992),
Medel & López-González (1996)
, Medel & Vervoort (1998), Bouillon
et al.
(2004); De Vito (2006), Gravili (2006),
Gravili
et al
. (2008a)
.