Pseudobranchiomma

Capa, María & Murray, Anna, 2015, A taxonomic guide to the fanworms (Sabellidae, Annelida) of Lizard Island, Great Barrier Reef, Australia, including new species and new records, Zootaxa 4019 (1), pp. 98-167 : 148

Pseudobranchiomma sp. 1

( Fig. 21A–B )

Material examined. Queensland, Great Barrier Reef: AM W.40930 (1), North Direction Island, 14°44′43′′S, 145°30′18′′E, fine coral rubble, 1 m, 26 Aug 2010.

Description of material examined. Specimen measuring 13 mm long and 1 mm wide, with seven thoracic and more than 18 abdominal segments ( Fig. 21A ). Live specimen with radiolar lobes pigmented in red with bright yellow radiolar tips ( Fig. 21A–B ). Body light orange, interramal eyespots conspicuous on both thoracic and abdominal chaetigers. Preserved specimen retains the pigmented radiolar lobes, though faded to dark purple; preserved body pale with distinct interramal eyespots. Radiolar crown with basal lobes slightly involuted ventrally; dorsal and ventral basal flanges absent. Basal membrane reduced. Radiolar flanges inconspicuous, lacking serrations. Four rows of vacuolated cells supporting radioles basally, not extended into radiolar flanges. Radiolar eyes absent. Dorsal lips with medium length dorsal radiolar appendages; dorsal pinnular appendages absent. Ventral lips and parallel lamellae present, with prominent ventral sacs directed outside of the branchial crown. Collar with dorsal margins separated by a wide gap, lateral margins smooth and large ventral lappets separated by a midventral incision. Glandular ridge absent on anterior chaetigers. Anterior four thoracic ventral shields separated from adjacent tori by a gap, posterior thoracic shields in contact with tori; first ventral shield with m-shaped anterior margin. Interramal eyes conspicuous ( Fig. 21 C–D). Posterior peristomial ring collar with narrowly-hooded chaetae arranged in oblique rows. Following thoracic chaetigers with conical notopodia; superior thoracic chaetae elongate narrowly-hooded, inferior chaetae spine-like. Neuropodial uncini avicular, with 2–3 rows of teeth above main fang, well developed breast and short handle. Companion chaetae absent. Abdominal chaetigers with short conical neuropodia, with narrowly-hooded superior chaetae and spine-like inferior chaetae. Notopodial uncini similar to thoracic. Pygidium conical, with eyespots on both sides. Peristomial cirrus absent. Tube unknown.

Remarks. This species seems to be undescribed and will be dealt with in a revision of the genus in Australia (Capa & Murray in prep). It is characterised by the absence of radiolar flanges, the absence of radiolar eyes, the collar margins separated by a wide gap and its colour pattern. This species belongs to Pseudobranchiomma “Group C” (according to Knight-Jones & Giangrande 2003). Other species included in this group are P. punctata Treadwell, 1906 , P. longa Kinberg, 1867 , P. m i n i m a Nogueira & Knight-Jones, 2002, P. perkinsi Knight-Jones & Giangrande, 2003 and P. tarantoensis Knight-Jones & Giangrande, 2003 . They differ from the specimen found at Lizard island due the presence of radiolar eyes (typical of P. longa and P. perkinsi ), the presence of collar margins fused to faecal groove (like P. punctata ) or the pigmentation pattern, with conspicuous spots in P. minima and P. tarantoensis ( Knight-Jones & Giangrande 2003) .

Habitat. Fine coral rubble, 1 m depth.

Distribution. Australia (Queensland: Lizard Island).

Figures

FIGURE 21. A – B. Pseudobranchiomma sp. 1, live specimen. A. Whole individual, ventral view, showing the bright colour pattern; B. Anterior end and radiolar crown, ventral view; C – D. Pseudobranchiomma sp. 2, preserved specimens; C. Radiolar crown and anterior thoracic chaetigers, lateral view; D. Detail of base of crown with diagonal collar and conspicuous interramal eyespots; E – G. Pseudopotamilla cf. reniformis. E. Live specimen, anterior end, lateral view; F. Same, dorsal view showing compound radiolar eye morphology and arrangement; G. Same, ventral view, showing the dorsoventral decrease in length of radioles.