The non-Siphonophoran Hydrozoa (Cnidaria) of Salento, Italy with notes on their life-cycles: an illustrated guide Gravili, Cinzia Vito, Doris De Camillo, Cristina Gioia Di Martell, Luis Piraino, Stefano Boero, Ferdinando Zootaxa 2015 3908 1 1 187 3BZHD Tichomiroff, 1887 Tichomiroff 1887 [151,653,404,430] Hydrozoa Eudendriidae Eudendrium Animalia Anthoathecata 23 24 Cnidaria species armatum   Material examined.HCUS-S 0 16 and HCUS-S 0 17 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula).   Description(based on our own observations; Marinopoulos, 1992; Marques et al., 2000a, b; Schuchert, 2008b):  Hydroid.Hydrorhiza rhizocaulomic; colonies erect, up to 65 mmhigh; hydrocaulus polysiphonic and branched, perisarc with several groups of annuli elsewhere; hydrocladia more or less alternate but not in the same plane, ringed basally and with several annulations at the base of renovated portions; hydranths typical of the genus; hypostome flared; with approximately 24 tentacles, proximal portion of tentacles devoid of nematocysts, the density of which gradually increases towards distal end where they form untidy bands; nematophores irregularly distributed throughout the colony, naked, large and thin, each borne on a pedicel. Gonophores as fixed sporosacs; females with unbranched spadix, males with 2–3 chambers. Colours: perisarc of the stem brown to yellowish (in younger parts).  Cnidome.Heterotrichous microbasic euryteles ( 5x3 to 6x 4 mm) on tentacles and ectoderm, also the same type( 8x4 to 9x4.5 µm) on the hypostome, the hydranth and on the hydrocaulus; butt thin.  Habitat type.Very abundant in small caves and crevices, from 1 to 40 m, generally on rocks ( Picard 1951a; Riedl 1966; Marinopoulos 1979, 1992; Boero & Fresi 1986; Gili 1986; Balduzzi et al.1995; Morri & Bianchi 1999; Morri et al.1999; Piraino et al.1999; Marques et al.2000a, b; Puce et al.2009).  Substrate.Concretions, massive sponges (  Ircinia, Petrosia), algae (  Corallina, Peyssonnelia, Halimeda tuna).  Seasonality.In the Ligurian Sea ( Boero & Fresi 1986; Puce et al.2009) in January, July March, December; in Salento waters (De Vito 2006; this study) in February, September–October.  Reproductive period.February–March, and from July to October ( Boero & Fresi 1986; Marques et al.2000a; De Vito 2006; this study).   Distribution.Mediterranean endemic ( Marques et al.2000a, b; Bouillon et al. 2004; Gravili et al.2008a; Schuchert 2008b; Soto Ãngel & Peña Cantero 2013).  Records in Salento.Common at Otranto, on overhangs and cave entrances (De Vito 2006; Gravili 2006; Gravili et al.2008a; this study).   Remarks.Colony form very similar to that of  E. rameum(Pallas)whose Mediterranean records might often be referred to  E. armatum.   References. Picard (1951a, 1958a), Gili (1986), Boero & Fresi (1986), Marinopoulos (1979, 1990, 1992), Medel & López-González (1996), Balduzzi et al.(1995), Morri & Bianchi (1999), Morri et al.(1999), Piraino et al.(1999), Marques et al.(2000a, b), Bouillon et al.(2004), Puce et al.(2005a, 2009), De Vito (2006), Gravili (2006), Gravili et al.(2008a), Schuchert (2008b).