Orthopyxis asymmetrica Stechow 1919
- Dataset
- The non-Siphonophoran Hydrozoa (Cnidaria) of Salento, Italy with notes on their life-cycles: an illustrated guide
- Rank
- SPECIES
Classification
- kingdom
- Animalia
- phylum
- Cnidaria
- class
- Hydrozoa
- order
- Leptothecata
- family
- Campanulariidae
- genus
- Orthopyxis
- species
- Orthopyxis asymmetrica
description
Description (based on our own observations; Piraino & Morri 1990; Peña Cantero & Carrascosa 2002): Hydroid. Hydrorhiza as creeping stolon system; colonies stolonal; hydranth pedicels twisted spirally over their whole length and bearing a single distal hydrotheca with a large and slightly asymmetrical basal spherule; basal chamber and hydrotheca with strongly asymmetrical perisarc thickening maximal at base and smoothly decreasing towards aperture. Gonothecae: female gonophores on the hydrorhiza bellshaped, laterally flattened, with short annulated pedicels and orange-coloured eumedusoids with 4 radial canals, and 4 – 8 interradial statocysts. Habitat type and substrate. Littoral species reported from near the tidal level to 25 m depth (García Carrascosa 1981; Gili 1986) on leaves of Posidonia oceanica. Cnidome. Microbasic mastigophores. Seasonality. In the Mediterranean Sea colonies occur in February, July (García-Rubies 1987 as Campanularia asymmetrica), March, April (De Vito 2006; this study), May (Piraino & Morri 1990), and September (Giovannetti et al. 2010). Reproductive period. May (Piraino & Morri 1990) in the Tyrrhenian Sea.
discussion
Remarks. Cornelius (1982) considered Campanularia asymmetrica as conspecific with Orthopyxis integra. Moreover, Östman et al. (1987) did not find distinct differences in the cnidome of both species. Nevertheless, Peña Cantero & García Carrascosa (2002) and many authors studying Mediterranean material keep the two species distinct.
distribution
Distribution. Mediterranean endemic (Medel & López-González 1996; Bouillon et al. 2004; Gravili et al. 2008 a; Soto Ãngel & Peña Cantero 2013). Records in Salento. Rare at Otranto (De Vito 2006; Gravili 2006; Gravili et al. 2008 a; this study), and Porto Cesareo (Andreano 2007).
materials_examined
Material examined. HCUS-S 118 (Hydrozoa Collection, University of Salento — fauna of the Salento Peninsula).
Name
- Homonyms
- Orthopyxis asymmetrica Stechow 1919