ON RECENT SPECIES OF SPIRASERPULA REGENHARDT, 1961 



91 



thorax, and has 6 radioles and a short club-shaped rudimen- 

 tary operculum on each side. The radioles are about 0.4 mm 

 long and end in short pinnule-free tips. Two clusters of dark 

 brown prostomial ocelli are present. There are 7 thoracic 

 chaetal tufts on one side, but the number on the other side 

 and the extent of the thoracic membranes cannot be deter- 

 mined due to the damaged thorax. 



The first worm is spirally coiled along the substratal plane 

 (Fig. 27, E). The length of the thorax and abdomen is 

 13.8 mm, of which the posterior portion of about 1.18 mm is 

 abruptly narrower than the rest of the abdomen. The entire 

 length of the third worm is about 7.0 mm, radioles 1.3 mm, 

 thorax and abdomen 5.7 mm; it has 7/6 radioles, and thoracic 

 width of 0.35 mm. 



There are 7 thoracic chaetal tufts on each side in one worm, 

 6/7 in the other. The thoracic membranes end between 

 chaetal tufts 6 and 7 on the left, and 5 and 6 on the right 

 (Fig. 27, E,F). Thoracic glands are absent. The number of 

 abdominal segments is 102, with capillaries on the last 6. A 

 mid-ventral longitudinal groove traverses the entire abdomen 

 and thorax (Fig. 27, E, F). 



Each collar fascicle bears about 4 bayonet chaetae. They 

 have long serrated blades, a short unserrated notch, and 

 several teeth on the basal boss (Fig. 27, G-J). Thoracic uncini 

 usually bear 4 teeth in a single row (Fig. 27, K). The anterior 

 abdominal uncini also possess 4 teeth in a single row, but the 

 3 posterior teeth are not closely appressed, as in the Indone- 

 sian specimens (Fig. 27, L). Flat trumpet chaetae number 

 about 3 per bundle. Since their edge is curved, details on the 

 anterior tooth cannot be observed. 



The third sample from Lizard Island, Queensland agrees 

 with the first and the Indonesian specimens in all important 

 characters (Fig. 27, A-J). The fully formed operculum is an 

 unlobed funnel with n shallow distal concavity (Fig. 28, C,D), 

 while in the earlier stages it is spherical or nearly spherical 

 (Fig.28, E-G). 



The dry tubes from Loyalty Islands (Fig.28, K-Q) 

 appeared to be brownish, but regained the typical mustard 

 colouration when immersed in alcohol. One fragment shows 

 branching (Fig.28, K). Internally there is only a smooth 

 ventral ridge (Fig.28, N-Q), which is clearly T-shaped in 

 places (Fig.28, Q); it is markedly so and occupies a larger part 

 of the lumen in some tubes which are comparatively very 

 thick-walled (Fig.28, N). 



The collection from Ras Mohammed, Sinai, consists of 

 tubes with fragments of worms (Fig.28, R-V). The tubes 

 have an overall mustard colour, but the anterior portions 

 (Fig.28, R,S) have pinkish peristomes, and a conspicuous 

 granular overlay along the lateral borders of the attached 

 portions (Fig.28, S). The medial overlay is scute-shaped, but 

 not as prominent as in the first Lizard Island sample. A 

 smooth ventral ridge is present (Fig.28, T-W), which is 

 T-shaped in its fully formed condition (Fig.28, T,U,W). 

 Those details of the worm that still could be observed (collar 

 chaetae, ends of thoracic membranes) agree with the data 

 given above. 



The samples from Elat, Israel, agree with regard to tube 



colouration, the smooth ventral longitudinal ridge and other 

 important characters. No. 154 is a single specimen on a piece 

 of coral rubble. The granular overlay is translucent in places; 

 transverse scutes are not seen medially, but this may be 

 because it is a juvenile. The worm has a total length of 

 3.6 mm; reddish prostomial ocellar clusters are present; its 

 thorax is 0.2 mm wide; gills 1.0 mm long, with short pinnule- 

 free tips; the number of thoracic chaetal tufts L?/R7; its 

 abdomen 1.9 mm long, with 24 segments and capillaries on 

 the last 4. There are 3 bayonet chaetae per fascicle, each with 

 an elongated blade, a short unserrated notch and several 

 teeth on the basal boss. Anterior abdominal uncini bear 4 

 teeth in a single row. An operculum had yet to be developed. 

 However, an operculum was observed in sample 311. A 

 schizont was separated from sample 244. 



Etymology. Named after the Indonesian-Dutch Snellius II 

 Expedition which enabled the second author to collect exten- 

 sively in Indonesian waters. 



Habitat and distribution. A reef dweller occurring at 

 depths of about 15-30 m. Appears to be the most widely 

 distributed species of the genus. Hitherto collected from the 

 northern Red Sea, Indonesia (Flores Sea), Australia (Great 

 Barrier Reef) and W. Pacific (S. Japan to New Caledonia). 



Spiraserpula lineatuba (Straughan, 1967) 



(Figs. 29, A-O; 30, A-M; 3, L; Pl.l, A, C & D, PI. 3, 



E-G) 



Synonymy. Serpula lineatuba Straughan, 1967, pp. 211-212, 

 Fig.5a-g. 



Material examined. 



New South Wales: 1. Sydney, Long Reef, underside of rocks, 

 LWS,27.ii.l965, legit D. Straughan (HOLOTYPE, 

 AM4018). 2. Sydney, Long Reef, rocks just below LWS, 

 Colloroy, Stn. 30, 27. i. 1964 (Topotypical material, 2 speci- 

 mens and several tubes, AM4019, ZMA V. Pol. 3450, 

 BM(NH) 1992.51). 3. Norah Head, at foot of light house, 

 from bottom of tidal pools at low-tide, from undersides of 

 boulders, legit H. A. ten Hove, 12. iv. 1986, Stn. 31 (5 out of 

 several specimens, AM W20340). 4. Split Solitary Island, 

 rocky island area with corals, algae and little sand, from 

 ceiling of small cave, 12-19 m, legit H. A. ten Hove, P. 

 Hutchings and R. Phipps, 26. iv. 1986, Stn. 36 (18 out of 

 several specimens, ZMA V.Pol. 3709, USNM 130996, 

 BM(NH) 1992.40-50, AM W20163, QM, NSMT). 5. South 

 Solitary Island, S of light house, rocky area, cobbles and 

 corals, little sand, 12-20 m, legit H. A. ten Hove, P. Hutch- 

 ings and R. Phipps, 27. iv. 1986, Stn. 37 (3 out of several 

 specimens, BM(NH) 1992.52-60). 



Type locality. Sydney, Long Reef (Australia). 



Description. 



According to the original description (Straughan, 1967), the 

 tube is circular in cross-section, white, with a pair of dark 

 pink lateral longitudinal stripes, pale pink dorsal surface. The 



Fig. 27 Spiraserpula snellii sp. nov. From Stn. 20, Lizard Island, Australia: A, Adult tube showing flattened coil form, granular overlay, 

 which is scutate medially, granular laterally and has a transverse thickened peristome. B, Aggregation of tube fragments with unserrated 

 ventral ridge, T-shaped in cross-section. C, Scutate juvenile tube with some transverse thickenings; granular overlay not yet developed. D, 

 worm showing radioles, rudimentary operculum and collar. E, worm from tube figured in A, showing thoracic membrane, ventral 

 longitudinal groove. F, Anterior part of latter, showing lack of apron and thoracic membrane ending on the 6th chaetiger on the left side. 

 G-J, Bayonet chaetae, all from same fascicle. K, Thoracic uncini. L, Anterior abdominal uncini. 



