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
Halocoryne epizoica
Hadzi, 1917
Fig. 46
A–F
See Schuchert (2010) for a complete synonymy.
Material examined.
HCUS-S 0 51 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula)—polyp stage.
Description
(based on our own observations;
Hadzi 1917a
,
b
;
Brinckmann-Voss 1970
; Bouillon 1974;
Piraino
et al.
1992
; Schuchert 2010):
Hydroid.
Hydrorhiza reticular, embedded in bryozoan colonies; colonies stolonal, polymorphic; gastrozooids cylindrical, very thin, sessile, naked, lacking tentacles but with 2 prominent ectodermal swellings containing stenoteles on opposite sides of the mouth; dactylo-gonozooids stouter than gastrozooids, without mouth and tentacles, with a terminal spherical cnidocyst cluster and up to 5 additional cnidocyst clusters along one side of the body or arranged in an interrupted spiral towards hydrorhiza. Colours: gonozooids dark red, other polyps dark red to transparent.
FIGURE 46.
Halocoryne epizoica
:
A
, general aspect of fertile colony;
B
, partly spent male eumedusoid;
C
, particular of a marginal bulb with a nematocyst patch;
D
undischarged macrobasic eurytele (?);
E
,
F
, discharged and undischarged macrobasic mastigophores (D, E, and F same scale bar) (modified after Piraino
et al.
1992). Scale bars: A, 1.0 mm; B, 0.5 mm; C, 0.1 mm; D, E, F, 10.0 µm.
Eumedusoid:
liberated or not, borne singly or in clusters on short pedicels on lower part of dactylogonozooids, bell-shaped with 4 exumbrellar cnidocyst pouches connected with marginal bulbs, manubrium reaching two thirds the height of subumbrellar cavity, without mouth; 4 radial canals; gonads completely encircling manubrium; 4 perradial marginal bulbs, without tentacles. Colours: dark red due to dense granules identical to those of the dactylo-gonozooids.
Habitat
type
and substrate.
Polyps grow in association with the bryozoan
Schizoporella sanguinea
(depth range:
0–40 m
, also up to
100 m
) (
Hadzi 1917a
,
b
;
Piraino
et al.
1992
; this study).
Seasonality.
From January to December in Salento waters (De Vito 2006; this study).
Reproductive period.
Fertile colonies occur in April, June–October (De Vito 2006; this study) in Salento waters.
Cnidome.
Stenoteles of two sizes (polyp); stenoteles of two sizes, macrobasic euryteles (?), and macrobasic mastigophores (medusa).
Distribution.
Endemic to the Mediterranean Sea (
Brinckmann-Voss 1970
;
Piraino
et al.
1992
; Bouillon
et al.
2004;
Gravili
et al.
2008a
; Schuchert 2010).
Records in Salento.
Common in the following localities: Torre dell’Inserraglio, Montagna Spaccata, La Strea, La Rotonda, Porto Badisco,
Marina
di Corsano, Palude del Capitano, Torre Vado, Ponte del Ciolo (
Presicce 1991
); Ionian and Adriatic coasts of Apulia (
Piraino
et al
. 1992
); Porto Cesareo (Boero
et al
. 2000); Otranto (De Vito 2006; Gravili 2006;
Gravili
et al.
2008a
; this study).
Remarks.
The whole life cycle was examined in the present study.
Halocoryne epizoica
engulfs and feeds on the lophophoral tentacles of its bryozoan host
Schizobrachiella sanguinea
(
Piraino
et al.
1992
)
.
References.
Hadzi (1917),
Picard (1958a)
,
Brinckmann-Voss (1970)
,
Petersen (1990)
,
Piraino
et al.
(1992
,
1999
), Boero
et al.
(2000), Bouillon
et al.
(2004), De Vito (2006), Gravili (2006),
Gravili
et al.
(2008a)
, Schuchert (2010).