82 



T.G. PILLAI AND HA. TEN HOVE 



Table 17 5. deltoides sp. nov. Some measurements and counts on 

 the holotype and 2 paratypes. 





Holotype 



Paratype 

 1 



Paratype 

 6 



Length of operculum and peduncle 



Length of operculum 



Diameter of operculum 



No of opercular lobes 



No. of radioles (L/R) 



No. of thoracic chaetal tufts (L/R) 



0.94 mm 

 0.38 mm 

 0.44 mm 



22 

 5/6 



8/7 



1.2 mm 

 0.52 mm 

 0.35 mm 



26 



6/6 



6/8 



3.2 mm 

 0.48 mm 

 0.41 mm 



22 

 7/7 

 111 



12.5 mm long, has about 75 segments, and the latter bear 

 reddish-brown granular material ventro-laterally. 



The collar fascicles bear 2-6 bayonet chaetae. Each has a 

 long serrated blade, a short unserrated notch, and about 2-6 

 teeth on the basal boss (Fig. 22, H-I, L-N). Thoracic uncini 

 bear about 5 teeth in a single row (Fig. 22, J,K); anterior 

 abdominal uncini are similar and bear 5-7 teeth. 



Etymology. The specific name refers to the delta-shaped 

 serrations of the internal dorsal ridge. 



Habitat and distribution. Found on calcareous stones at 

 depths of 75-90 m. Hitherto collected only from Sumba 

 (Indonesia). 



Spiraserpula sumbensis sp. nov. 

 (Figs. 23, A-U; 3, H) 



Material examined. 



Sumba (Indonesia): Snellius II 4.051, NE coast of Sumba, E 

 of Melolo, 09°53.5'S 120°42.7'E, 75-90 m, (HOLOTYPE: 

 RMNH 18297; 1 PARATYPE: ZMA V. Pol. 3737; 1 

 PARATYPE: BM(NH) 1992.72). 



Type LOCALITY. Sumba (Indonesia). 



Description. 



tubes: White to very faintly pinkish. A small species with 

 external tube diameter only up to about 0.5 mm, and a lumen 

 of about 0.25 mm wide. A granular overlay consisting of 

 extremely fine granules can be seen under special illumina- 

 tion. Tubes are circular in cross-section and bear faint trans- 

 verse wrinkles (Fig. 23, A-C, O). 



ITS consist of a dorsal ridge and a ventral ridge, which are 

 both unserrated, wedge-shaped in cross-section (Fig. 3, H), 

 and partially divide the lumen into somewhat asymmetrical 

 left and right halves (Fig. 23, C,D). The two ridges are light 



Table 18 S. sumbensis sp. nov. Measurements and counts. 



Length of op. & peduncle (mm) 

 Length of operculum (mm) 

 No. of lobes 

 No. of radioles 

 No. of thoracic chaetal tufts 

 Thoracic membrane ends 

 (Fig.23,Q) 



Paratype 



Paratype 





1 



2 



Left side 



Right side 





1.2 



1.0 



1.2 



0.36 



0.36 



0.35 



19 



21 



17 



5 



5 



4/4 



pink and opaque. In cross-section they consist of a lens- 

 shaped whitish kernel in the inner hyaline tube layer; the 

 outer tube layer is opaque. 

 worms: The holotype (Fig. 23, E-G), has a total length of 



7.0 mm, thoracic width of 0.26 mm, an abdominal length of 



5.1 mm and 66 segments, with capillaries on the last 17. The 

 length of the operculum plus peduncle is 1.3 mm, the length 

 and diameter of the operculum 0.38 mm and 0.26 mm, 

 respectively. The operculum is zygomorphic (Fig. 23, E,F). It 

 has a distal concavity which extends as far as the inter-radial 

 grooves. The 15 radii end in somewhat acutely triangular 

 marginal lobes with smooth tips. The peduncle is slender, but 

 somewhat expanded before the constriction below the oper- 

 culum. There are 5 radioles on each side, with the operculum 

 on the left side and a short filamentous rudimentary opercu- 

 lum on the right (Fig. 23, E). The short pinnule-free tips are 

 about 1/7-1/8 the total length of the radioles. Thoracic 

 chaetal tufts number 8 on each side. The thoracic membrane 

 ends on the fifth chaetiger on the left, but it is difficult to 

 determine its extent on the right. One tiny prostomial eye 

 appears to be present on the right side, the left side is 

 damaged. Thoracic glands could not be detected in the 

 material. 



One paratype (Fig. 23, O-Q) has an incomplete abdomen. 

 It is the first specimen encountered in this genus with two 

 equally well-developed opercula (Fig. 23, 0,P). The thorax of 

 the second paratype is missing, the remaining abdomen has 

 54 segments, 12 of them with capillaries. Some measurements 

 and other data are given in Table 18: 



The paratypes agree with the holotype with regard to the 

 tube, operculum, radioles, and chaetae. The opercula are 

 somewhat zygomorphic. 



Collar fascicles bear 4 fully formed bayonet chaetae in the 

 holotype; 3 fully formed bayonet chaetae and a newly formed 

 one deep within the fascicle in paratype 1. Each bayonet 

 chaeta (Fig.23,H-K, R-U) consists of a long serrated blade, a 

 moderately long unserrated notch, which is about 1/6-1/7 the 

 length of the blade, and several teeth on the basal boss. 

 Thoracic uncini appear to have a row of 7-9 teeth in side 

 view, but more than one row as seen in edge view (Fig. 23, L). 

 Anterior abdominal uncini are similar, but appear to have 

 fewer teeth in side view (Fig. 23, M). Flat trumpets number 

 four in each anterior bundle, their curved distal ends have a 

 poorly developed hook on one side and are comparatively 

 elongated on the other (Fig. 23, N). Capillaries occur in the 

 posterior 12-17 chaetigers. 



Etymology. Named after the type locality. 



Habitat and distribution. Found on calcareous stones at 

 depths of about 75-90 m. Hitherto collected only from 

 Sumba (Indonesia). 



Spiraserpula iugoconvexa sp. nov. 

 (Figs. 24, A-K; 25, A-Q; 3, 1) 



Material examined. 



NE Flores Sea to SW Banda Sea (Indonesia): 1. Taka Bone 



Rate(Tiger Islands), Snellius II 4.139B, S of Tarupa Kecil, 

 06°30'S 121°8'E,depth -30 m, (HOLOTYPE: RMNH 18295; 

 PARATYPE I: ZMA V.Pol.3735). 2.Tukang Besi Island, 

 Binongko, Snellius II 4.044B, SW of Taipabu, Banda Sea, 

 5°56'S 123°58.5'E, down to 25 m, (PARATYPE II: BM(NH) 

 1992.39). Queensland (Australia): 3. Lizard Island, S. South 

 Island, sloping silty reef, little coral cover, legit H. A. ten 



