Ventromma halecioides (Alder, 1859)

Gravili, Cinzia, Vito, Doris De, Camillo, Cristina Gioia Di, Martell, Luis, Piraino, Stefano & Boero, Ferdinando, 2015, The non-Siphonophoran Hydrozoa (Cnidaria) of Salento, Italy with notes on their life-cycles: an illustrated guide, Zootaxa 3908 (1), pp. 1-187 : 110-111

Ventromma halecioides (Alder, 1859)

Fig. 78 A–C

See Peña Cantero & García Carrascosa (2002) for a complete synonymy.

Material examined. HCUS-S 0 85 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula). Description (based on our own observations; Cornelius 1995; Ansín Agís et al. 2001 as Kirchenpaueria halecioides ):

Hydroid. Hydrorhiza polysiphonic, linear, colonies erect, pinnate; hydrocauli often branched, up to 40 mm high, basally polysiphonic, monosiphonic parts of the axis separated into internodes by transverse nodes, each segment with a lateral apophysis distally bearing a naked nematophore, a cup-shaped nematotheca is borne laterally on the segment, above the apophysis; hydrocladia borne on the apophysis, alternate, heteromerously segmented, nodes transverse, basal part beginning with a short athecate internode, thecate segments with one hydrotheca and 2 nematothecae, one median superior and one median inferior at some distance from the hydrothecae; hydrotheca cup-shaped, abcauline wall slightly convex, on distal half of internode, almost completely adnate, rim smooth and circular, aperture 80º with the axis; nematothecae two-chambered, small, basal chambers very short, distal one scoop-shaped, with adcauline embayment. Gonothecae on the hydrocaulus and hydrorhiza, barrel-shaped, narrowed basally, truncate distally, with a circular lid, walls with transverse and distinct ribs.

Cnidome. Microbasic mastigophores, atrichous isorhizas, and basitrichous isorhizas.

Habitat type. Intertidal pools to sublittoral (depth range: 0–20 m, reaching to 100 m) ( Boero & Fresi 1986; Cornelius 1995; Ansín Agís et al. 2001).

Substrate. Records on piece of wood, sea grasses, hydroids, algae, artificial substrata, mussels, barnacles, bryozoans, Tunicata, sponges, and other organisms,

Seasonality. June–September ( Boero & Fresi 1986), November–December ( Bianchi et al. 1993b), November ( Galea 2007), April–September, December (Puce et al. 2009) in the western Mediterranean; November ( Piraino et al. 2013), January–December (De Vito 2006; this study) in Salento waters.

Reproductive period. Between spring and autumn ( Morri 1981b), summer ( Boero & Fresi 1986), June–July (Gili 1986), November ( Galea 2007) in the western Mediterranean; June–August (De Vito 2006; this study) in Salento waters.

Distribution. Cosmopolitan species ( Medel & Vervoort 1995; Medel & López-González 1996; Ansín Agís et al. 2001; Peña Cantero & García Carrascosa 2002; Bouillon et al. 2004; Gravili et al. 2008a; Soto Ãngel & Peña Cantero 2013).

Records in Salento. Moderately frequent at: La Strea, Porto Cesareo ( Faucci & Boero 2000); Costa Merlata ( Fraschetti et al. 2002); Torre Lapillo, S.ta Caterina, Costa Merlata ( Andreano 2007); Grotta del Ciolo (Denitto et al. 2007); Otranto (De Vito 2006; Gravili 2006; Andreano 2007; Gravili et al. 2008a; Stabili et al. 2008; Piraino et al. 2013; this study).

Remarks. Occurrence of athecate internodes in hydrocladia is much varied (for more details see Ansín Agís et al. 2001). Boero (1981c) described a high variability, determined by water movement conditions. In calm waters colonies can become very high, whereas they remain small, and almost monosiphonic, in turbulent water. The hydrorhiza is always fascicled.

References. Stechow (1919, 1923), Billard (1926), Leloup (1934), Picard (1952, 1958a), Rossi (1971), Schmidt (1973), García-Corrales et al. (1978), Morri (1979d, 1980b, c), Boero (1981a, b, c), Gili & García-Rubíes (1985), Morri & Bianchi (1985), Boero & Fresi (1986), Gili (1986), Barangé & Gili (1987), Piraino & Morri (1990), Riedl (1991), Cornelius (1995), Medel & Vervoort (1995), Medel & López-González (1996), Piraino et al. (1999), Faucci & Boero (2000), Ansín Agís et al. (2001), Fraschetti et al. (2002), Peña Cantero & García Carrascosa (2002), Bouillon et al. (2004), De Vito (2006), Gravili (2006), Denitto et al. (2007), Galea (2007), Çinar et al. (2008), Gravili et al. (2008a), Morri et al. (1991, 2009), Puce et al. (2009), Piraino et al. (2013) as K. halecioides .

Figures

FIGURE 78. Ventromma halecioides: A, general aspect of a colony; B, particular of a colony; C, gonotheca (A drawn by F. Boero; B, C drawn by C. G. Di Camillo). Scale bars: A, 1.0 cm; B, C, 500 µm.