Orthopyxis integra MacGillivray 1842

Orthopyxis integra (MacGillivray, 1842)

Fig. 113 A, B

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

Material examined. HCUS-S 120 (Hydrozoa Collection, University of Salento—fauna of the Salento Peninsula).

Description (based on our own observations; Cornelius 1995; Schuchert 2001a; Peña Cantero & Carrascosa 2002):

Hydroid. Hydrorhiza tortuous, anastomosing and thick; colonies stolonal; hydranth pedicels thick-walled and usually undulated throughout, with sub-hydrothecal spherule; hydranth with 25–30 tentacles; hydrothecae bellshaped, thick walled in variable degree, rim smooth, usually unthickened and often flared, basally with a perisarc ring limiting a small spherical chamber. Gonothecae sac-shaped, contour often irregular, truncate distally, usually flattened, but sometimes circular in transverse section, on stolons, with short pedicel, females with 1–3 eumedusoid buds.

Eumedusoid. Umbrella bell-shaped, higher than wide, mesoglea fairly thick; 4 radial canals either meeting at apex or each closing before they meet, each one with one irregularly-lobed sac-like outgrowth midway along each side; gonads on lobes of radial canals outgrowths; no marginal tentacles; 8 statocysts; sexually mature at release.

Cnidome. Microbasic mastigophores.

Habitat type. Eurybathic species found in the Mediterranean from the tidal level to 35 m depth (Stechow 1919; Boero & Fresi 1986; Gili 1986).

Substrate. A wide variety of algae, phanerogams, ascidians, barnacles, mussel shells, other hydroids and cirripedes, bryozoans, anthozoans, sponge.

Seasonality. Present throughout the year (Boero & Fresi 1986; Peña Cantero & García Carrascosa 2002; Puce et al. 2009) in the western Mediterranean; February–September (De Vito 2006; this study) in Salento waters.

Reproductive period. In the Mediterranean Sea fertile colonies occur in April (Stechow 1919); May (Boero & Fresi 1986); June (Stechow 1919; Boero & Fresi 1986); July (Picard 1958b; Boero & Fresi 1986; Peña Cantero & García Carrascosa 2002); August (Boero & Fresi 1986; Morri & Bianchi 1999), and September (Boero & Fresi 1986).

Distribution. Cosmopolitan (Broch 1918; Millard 1975; Cornelius 1982; Medel & Vervoort 2000; Medel & López-González 1996; Bouillon et al. 2004; Gravili et al. 2008a).

Records in Salento. Moderately frequent at: La Strea, Porto Cesareo (Presicce 1991; Faucci & Boero 2000; Ventura 2011); Costa Merlata (Fraschetti et al. 2002; Andreano 2007); Otranto (Fraschetti et al. 2002; De Vito 2006; Gravili 2006; Gravili et al. 2008a; this study); Torre Lapillo, Torre dell’Inserraglio, S.ta Caterina (Andreano 2007). Other Apulian records: Gargano (Fraschetti et al. 2002).

Remarks. The hydroid stage and the eumedusoid were seen in the present study. Among the Campanulariidae, O. integra is unusually varied in morphology (for more details see Cornelius 1982; Vervoort 1993).

References. Pieper (1884) as Campanularia integra; Schneider (1898) and Lo Bianco (1909) as C. caliculata; Behner (1914) as Agastra rubra; Stechow (1919) as C. caliculata and as O. compressa; Vatova (1928); Leloup (1934) and Rossi (1950) as C. integra; Picard (1951a, 1958a); Kramp (1959); Riedl (1959, 1966, 1991) and Yamada (1965) as O. caliculata; Stefani (1959) as C. caliculata; Teissier (1965); Riedl (1966) as O. caliculata and O. compressa; Morri (1979c, 1980b); Boero (1981b, c) as C. integra; García Carrascosa (1981) as Campanularia; Marinopoulos (1983) as O. caliculata; Isasi (1985), Balduzzi et al. (1986), Boero & Fresi (1986), Gili (1986), Roca (1986), Östman et al. (1987), Ramil (1988), Gili et al. (1989), Riedl (1991), Vervoort (1993), Altuna (1994), Medel & López-González (1996), Morri & Bianchi (1999), Piraino et al. (1999), Faucci & Boero (2000), Medel & Vervoort (2000), Schuchert (2001a), Fraschetti et al. (2002), Peña Cantero & García Carrascosa (2002), Bouillon et al. (2004), De Vito (2006), Gravili (2006), Galea (2007), Gravili et al. (2008a), Morri et al. (2009), Puce et al. (2009), Ventura (2011).