Corydendrium parasiticum (Linnaeus, 1767)

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 : 38-40

Corydendrium parasiticum (Linnaeus, 1767)

Fig. 25 A–C

See Schuchert (2004) for a complete synonymy.

Material examined. HCUS-S 0 30 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula).

Description (based on our own observations; Schuchert 2004):

Hydroid. Colonies erect, up to 5 cm high; hydrocauli polysiphonic, much branched; perisarc firm, moderately thick, smooth or with some wrinkles and often encrusted with detritus and silt, becoming thin at hydranth base and ending below tentacles; hydrocladia branching irregularly in one or more planes, adnate to main axis basally but gradually curving outwards and becoming free distally, secondary branches occur in the same way; hydranths elongate, constricted basally (below perisarcal tube); hypostome conical, prominent; with 40 or more filiform tentacles, scattered throughout the body of the hydranth. Gonophores as long, slender cylinders wholly contained within perisarcal tube, arising from coenosarc and lying parallel to it, without spadix; females with about 13 eggs, extruded from perisarc when mature but remaining attached to the end of tube until developed into planulae.

Cnidome. Desmonemes and microbasic euryteles.

Habitat type. Rocky cliffs, concretions ( Schuchert 2004).

Substrate. Grows most often on rock.

Seasonality. In the Tyrrhenian Sea ( Lo Bianco 1909) from June to October; summer in the Ligurian Sea (Puce et al. 2009); in Salento waters (De Vito 2006; this study), present in February, July, November.

Reproductive period. In the Tyrrhenian Sea in August–September ( Lo Bianco 1909), and June–August ( Neppi 1921).

Distribution. Circumglobal in tropical and subtropical seas ( Fraser 1938; Millard & Bouillon 1973; Millard 1975; Wedler & Larson 1986; Rees & Vervoort 1987; Calder 1988; Migotto 1996; Medel & López-González 1996; Watson 1999; Bouillon et al. 2004; Schuchert 2003, 2004; Gravili et al. 2008a).

Records in Salento. Rare in the Gulf of Taranto, Otranto (De Vito 2006; Gravili 2006; Gravili et al. 2008a; Piraino et al. 2013; this study).

Remarks. The taxonomic history and synonymy of this species are given by Calder (1988), and Schuchert (2004) (for more details see Neppi 1917; Wedler & Larson 1986).

References. Motz-Kossowska (1905), Lo Bianco (1909), Stechow (1919), Picard (1958a), Rossi (1971), Millard (1975), Gili (1982), Boero & Fresi (1986), Calder (1988), Medel & López-González (1996), Piraino et al. (1999), Bouillon et al. (2004), Schuchert (2004), De Vito (2006), Gravili (2006), Gravili et al. (2008a), Puce et al. (2009), Piraino et al. (2013).

Figures

FIGURE 25. Corydendrium parasiticum: A, distal branches with hydranths; B, adnate branch; C, female gonophores (A, C same scale bar) (A, B drawn by L. Basso; C drawn by C. G. Di Camillo). Scale bars: A, B, C, 1.0 mm.