Perkinsyllis augeneri ( Hartmann-Schroeder , 1979)

Faulwetter, Sarah, Chatzigeorgiou, Georgios, Galil, Bella S. & Arvanitidis, Christos, 2011, An account of the taxonomy and distribution of Syllidae (Annelida, Polychaetes) in the eastern Mediterranean, with notes on the genus Prosphaerosyllis San Martin, 1984 in the Mediterranean, ZooKeys 150, pp. 281-326 : 286

Perkinsyllis augeneri ( Hartmann-Schroeder, 1979)

Pionosyllis augeneri Hartmann-Schröder, 1979: 98, figs 119-125; 1980a: 52; 1981: 32, fig. 52 (Non Hartmann-Schröder 1991: 35); San Martín and Hutchings 2006: 326. figs 57 a–j, 58 a–f.

Perkinsyllis augeneri : San Martín et al. 2009: 26.

Material examined.

Haifa Bay, Israel: ALA-IL-7 (7 ind.) [coll. 11.10.2009].

Type locality.

Boone, west Australia.

Distribution.

Australia, New Zealand. Mediterranean Sea: LB. New record for the Mediterranean Sea.

Habitat.

Intertidal and shallow subtidal depths, in coarse coralline sand, in muddy sand and seagrass beds ( San Martín and Hutchings 2006).

Taxonomic characters.

Prostomium pentagonal with 4 eyes in trapezoidal arrangement, posterior pair closer together than anterior one. Palps longer than prostomium, basally fused. Antennae cylindrical, smooth, longer than prostomium and palps. Tentacular cirri similar to antennae but slightly longer. Dorsal cirri of some anterior segments slender, longer than body width, some shorter, in midbody alternating short and long cirri, posteriorly all shorter than body width. Parapodia with 9-10 falcigers per fascicle anteriorly, 6-7 posteriorly. Shafts smooth or slightly serrated. Blades with marked dorso-ventral gradation (dorsal ones 3 times longer than ventral ones), coarsely serrated, with small subdistal tooth. After proventriculum, dorsal blades unidentate, elongated, spiniger-like, twice as long as anteriorly, ventral blades stout, with strong serration, especially basally. Dorsal simple chaeta first appearing on midbody, blunt, subdistally serrated. Ventral simple chaetae posteriorly, bidentate, equally sized teeth forming a right angle, some long spines subdistally. Paired aciculae anteriorly, single ones posteriorly, with rounded, slightly enlarged tip. Pharynx through 4 chaetigers, pharyngeal tooth located anteriorly. Proventricle through 5 chaetigers with ca. 20-22 muscle cell rows.

Remarks.

The subfamilial affiliation of Perkinsyllis augeneri has not yet been fully resolved. In recent molecular phylogenies the species groups either within Exogoninae or as a sister group, and forms a sister clade of Eusyllinae in all analyses ( Aguado and Bleidorn 2010, Aguado et al. 2007).

The morphological characters of the Mediterranean individuals agree well with the description of San Martín and Hutchings (2006) from Australia. Therefore, a detailed description of the specimens is unnecessary here. The Mediterranean specimens show slight differences from the description of the Australian ones in the length of the pharynx (6-7 chaetigers in Australian specimens vs 5 in Mediterranean ones), and the number of falcigers per bundle in anterior chaetigers (ca. 15 in Australian specimens vs ca. 10 in Mediterranean ones). These differences might however be attributed to fixation and / or individual variation.

Until now, the species had been known only from north-west Australia and New Zealand, while the record from the Carribean Sea ( Hartmann-Schröder 1980a) is assumed to be a different species ( San Martín et al. 2009). The present findings thus extend the distribution range of the species to the eastern Mediterranean Sea. Since there are no intermediate records of the species from the Indian Ocean or Red Sea, this disjunct distribution suggests a potential human-induced introduction of the species to the Mediterranean Sea by vectors such as ballast water or fouling fauna on the hulls of ships. However, since the polychaete fauna of the Indian Ocean, Red Sea and eastern Mediterranean Sea is understudied, the species might have a truly circumtropical distribution. This is the second record of an Australian syllid species for the Mediterranean Sea (after Prosphaerosyllis longipapillata ( Hartmann-Schröder, 1979), recorded for the first time in 2003 in Cyprus ( Çinar et al. 2003)).