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
Plumularia setacea
(Linnaeus, 1758)
Fig. 90
A–D
See
Medel & Vervoort (1995)
and
Schuchert (2001a)
for a complete synonymy.
FIGURE 90.
Plumularia setacea
:
A
, general view of a colony;
B
, parts of stem showing origins of hydrocladia and gonothecae;
C
, detail of hydrocladium;
D
, gonotheca (A, B drawn by L. Basso; C, D drawn by C.G. Di Camillo). Scale bars: B, D, 500 µm; C, 250 µm.
Material examined.
HCUS-S 0 97 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula).
Description
(based on our own observations; Ramil & Vervoort 1992;
Cornelius 1995
;
Medel & Vervoort 1995
):
Hydroid.
Hydrorhiza tubular, variably ramified in accordance to the substrate; colonies erect, pinnate; hydrocauli monosiphonic, unbranched, but occasionally branched, up to ca
60 mm
, divided into internodes by transverse nodes, each segment bearing a basal and a distal nematotheca, the last one almost in the axil of a lateral apophysis; hydrocladia alternate, borne on stem apophyses, in the same plane, heteromerously segmented by transverse nodes into hydrothecate and non-hydrothecate internodes; hydrothecate internodes with one hydrotheca and 3 nematothecae, one inferior median one and 2 latero-superior ones, non-hydrothecate segments with one frontal nematotheca, usually with one perisarcal septum above and below it, septum also may occur basally on hydrothecate internodes; first hydrocladial internode athecate and shorter; hydrothecae cup-shaped, entirely adnate, rim even, aperture slightly tilted downwards; nematothecae all two-chambered, conical, basal chamber longer, apical one wider, with adcauline embayment. Gonothecae of both sexes on the same stem or not, typically in a continuous line towards the base of stem, female ones elongated, fusiform, smooth, narrower distally with a more or less developed tubular neck, with narrow and circular apical aperture, male ones narrower and smaller than females, less attenuate above, tapering to a minute orifice. Colours: stem pale to dark horn (dark brown in some old colonies).
Cnidome.
Microbasic mastigophores.
Habitat
type
.
Eurybathic species, in the Mediterranean Sea found from the tidal level to about
400 m
depth (
Broch 1933
; García
Carrascosa 1981
;
Boero & Fresi 1986
;
Roca 1986
; Ramil & Vervoort 1992).
Substrate.
Recorded on other hydroids, sponges, barnacles,
Posidonia
, algae, mollusc shells, bryozoans, other organisms, and biogenic banks.
Seasonality.
January–March (
Llobet i Nadal 1987
;
Llobet
et al.
1991
; Puce
et al.
2009), April (
Llobet i Nadal 1987
;
Llobet
et al.
1991
), July (
Llobet i Nadal 1987
;
Llobet
et al.
1991
;
Brahim
et al.
2010
), August (
Boero & Fresi 1986
;
Brahim
et al.
2010
), and November (
Boero & Fresi 1986
) in the several localities of the Mediterranean Sea; all year in Salento waters (De Vito 2006; this study).
Reproductive period.
February (
Ramil 1988
), March (
Stechow 1923
; Puce
et al.
2009), May (
Stechow 1919
;
Rossi 1961
), June (
Picard 1955
; Morri & Bianchi 1999), August and September (
Picard 1952
) in the several localities of the Mediterranean Sea; October–May (De Vito 2006; this study) in Salento waters.
Distribution.
Cosmopolitan (
Millard 1975
;
Cornelius & Ryland 1990
;
Medel & Vervoort 1995
;
Ramil
et al.
1998
; Bouillon
et al.
2004;
Gravili
et al.
2008a
).
Records in Salento.
Common at: La Strea, Porto Cesareo (
Presicce 1991
;
Denitto 1996
;
Faucci & Boero 2000
); Montagna Spaccata, Torre S. Emiliano, Ponte del Ciolo (
Presicce 1991
); Otranto (
Denitto 1996
;
Miglietta
et al
. 2000
;
Fraschetti
et al
. 2002
; De Vito 2006; Gravili 2006;
Andreano 2007
;
Gravili
et al.
2008a
;
Stabili
et al.
2008
;
Ventura 2011
;
Piraino
et al.
2013
; this study); Costa Merlata (
Fraschetti
et al
. 2002
;
Andreano 2007
); Il Chiapparo (C. Gravili unpublished observations).
Remarks.
For more details about the variability of this species see Ramil & Vervoort (1992).
References.
Broch (1912
,
1933
),
Stechow (1919
,
1923
),
Billard (1926)
,
Leloup (1934)
,
Rossi (1950
,
1961
,
1971
),
Picard (1952
,
1958a
),
Riedl (1959
,
1970
,
1991
),
Schmidt (1973)
,
Hughes (1975)
,
Chas & Rodriguez (1977)
, García-Corrales
et al.
(1978),
Morri (1980b)
, García
Carrascosa (1981)
,
Isasi (1985)
,
Boero & Fresi (1986)
, Gili (1986),
Roca (1986)
, Llobet i Nidal (1987),
Ramil (1988)
,
Llobet
et al
. (1991)
, Ramil & Vervoort (1992),
Alvarez Claudio (1993)
, Altuna (1994),
Medel & Vervoort (1995)
,
Medel & López-González (1996)
, Morri & Bianchi (1999), Morri
et al
. (1999),
Piraino
et al.
(1999)
,
Faucci & Boero (2000)
,
Miglietta
et al.
(2000)
,
Ansín Agís
et al.
(2001)
,
Fraschetti
et al.
(2002)
,
Peña Cantero & García Carrascosa (2002)
, Bouillon
et al.
(2004), De Vito (2006), Gravili (2006),
Gravili
et al.
(2008a)
,
Morri
et al
. (2009)
, Puce
et al.
(2009),
Brahim
et al.
(2010)
,
Bianchi
et al.
(2011)
,
Ventura (2011)
,
Piraino
et al.
(2013)
.