Proscoloplos cygnochaetus Day, 1954

Zhadan, Anna, 2020, Review of Orbiniidae (Annelida, Sedentaria) from Australia, Zootaxa 4860 (4), pp. 451-502 : 493

Proscoloplos cygnochaetus Day, 1954

Figure 25

Proscoloplos cygnochaetus Day, 1954: 21 , fig. 3a–f; 1967: 538, fig. 23.1e–g; Meyer et al. 2008: 879–889, fig. 1; Blake 2017: 118–120 , fig. 58a–f.

Proscoloplos confusus: Hartmann-Schröder 1962: 133–134 , figs. 161–164.

Proscoloplos bondi: Kelaher & Rouse 2003: 909–917 , fig. 2.

Material examined. Western Australia: King George Sound, Vancouver Peninsula, near Mistaken Island , 35°04’S, 117°56’E, 13.12.1983, intertidal, coll. H.E. Stoddart, AM W.23614, 6 specimens . New South Wales: Ben Buckler rocks at north end of Bondi Beach , coralline algal turf, 29.05.2000, coll. G. Rouse, 33°53’42”S, 151°16’48”E, AM W.29015, paratypes of P. bondi , 7 specimens .

Type locality. Tristan da Cunha .

Description. Body width 150–300 µm, length 2–3 mm, 22–38 chaetigers ( Fig. 25A, C ). Prostomium round, without eyes, two peristomial segments ( Fig. 25 A–D). Transition from thorax to abdomen indistinct. Branchiae from chaetiger 6–8, oval, same length as notopodia or slightly longer ( Fig. 25A, B ). Notopodial postchaetal lobes digitiform, increasing towards posterior ( Fig. 25A, D ). Neuropodial lobes short, papilliform, almost disappearing in abdomen ( Fig. 25A ). Notochaetae crenulated capillaries in all segments; neurochaetae crenulated capillaries in all segments, besides swan-shaped chaetae in abdominal segments (starting from chaetiger 6–9) ( Fig. 25B, E ). Pygidium with four short cirri ( Fig. 25A, C ).

Distribution (bases on literature). Chile, Argentina, South Africa, Atlantic French coast, Australia, Western Australia, New South Wales.

Habitat. Intertidal and upper subtidal, sand, algae.

Remarks. Proscoloplos cygnochaetus was described from the South Atlantic Ocean, Tristan da Cunha Island ( Day, 1954). Since, this species has been redescribed by Kelaher & Rouse (2003) (as P. bondi ), Meyer et al. (2008), and Blake (2017). Meyer et al. (2007) investigated both morphological and molecular data on three Proscoloplos species and concluded that Proscoloplos confusus Hartmann-Schröder, 1962 and Proscoloplos bondi Kelaher & Rouse, 2003 are junior synonyms of P. cygnochaetus . This was accepted by Blake (2017). The specimens studied here are in agreement with previous descriptions. The present study expands the distribution of P. cygnochaetus to Western Australia.

Figures

FIGURE 25. Proscoloplos cygnochaetus, A. AM W.29015, paratype of P. bondi, methylene blue staining; B–E. AM W.23614, compound microscope. A. General lateral view; B. Anterior end, dorsal view; C. General dorsal view; D. Anterior end, ventral view; E. Abdominal neuropodia with swan-shaped chaetae (sw).