78 



A.R.G. PRICE AND F.W.E. ROWE 



Family OPHIODERMATIDAE 



38. Cryptopelta granulifera H.L. Clark, 1909 



See. Clark & Rowe, 1971: 88; 128; Rowe & Gates, 1995: 394. 



Material. 801212B/1 (1). 



Collection sites. Chetlat, Lakshadweep (Laccadive) Islands. 



Habitat and depth. Coral rubble; 8 m. 



Remarks. Originally described from Mauritius. Rowe & Gates 

 (1995) describe the distribution as including tropical Australia, the 

 Indo-Malayan region and Philippine Islands. The specimen is iden- 

 tified here from the Laccadive Islands for the first time. 



39. Ophiarachna affinis Liitken, 1 869 



occurrence of spinelets on the discs of 4 specimens from Aldabra, 

 western Indian Ocean and 2 specimens from Palau in the western 

 Pacific Ocean which they examined suggested that Ophiochaeta 

 boschmai A.H. Clark, 1964 is a synonym of Ophiochaeta hirsuta 

 Liitken, 1869. They pointed out that Cherbonnier & Guille,1978, 

 had described a new species, O. crinita, based on a single specimen, 

 from Madagascar, but did not comment further. In the present 

 collection the specimen from the Lakshadweep Islands accords with 

 the description of boschmai in that the disc is granule-covered 

 dorsally but bears spinelets on its ventral surface. The specimen 

 from Pula We, on the other hand, accords with the description of 

 crinita in that the disc is covered dorsally and ventrally by elongate 

 spines. Considering the comments by Sloan et al. (1979), the two 

 specimens reported herein are referrred to O. hirsuta, with the 

 implication that O.crinita Cherbonnier & Guille should also be 

 referred to the synonymy on the basis that it exhibits the extreme 

 spiny form of O. hirsuta. 



I; 123; Sloan era/., 1979: 111; Rowe 42. Ophiodyscrita instratus (Murakami, 1944) n. comb. 



SEE. Clark & Rowe, 1971: 

 & Gates, 1995: 395. 



Material. 810425C/la,b (1). 



Collection sites. E. Sabang Bay, Pula We, Sumatra. 



Habitat and depth. Coral conglomerate; 3-6 m. 



Remarks. A.M. Clark (in Clark & Rowe, 1 97 1 : Note 83, p. 1 23) 

 describes in detail colour variation in Ophiarachna affinis and O. 

 mauritiensis de Loriol, concluding that specific distinction between 

 the two is difficult to make. In the present specimens with d.d. = 22 

 mm, the disc is uniformly brownish-grey and the dorsal side of the 

 arms has a broad longitudinal central dusky band either side of 

 which is a narrower pale band, the 3 bands being demarcated by 4 

 irregular, very narrow longitudinal dark bands. This corresponds to 

 A.M. Clark's form C colour pattern. If O. affinis and O. mauriti- 

 ensis are conspecific the species is clearly widely distributed in the 

 Indo-West Pacific region. 



40. Ophiarachna robillardi de Loriol, 1893 



See. Clark & Rowe, 1971: 



123. 



Material. 810126B/4 (1), 810213A/3 (2). 



Collection sites. Galle, Tangalla, Sri Lanka. 



Habitat and depth. Coral reef, 3-5 m. 



Remarks. This is a significant extension of range for this species 

 described from Mauritius. The species is recorded as having 5 arm 

 spines (H.L. Clark, 1909; size not recorded) but the present 3 

 specimens have 7-9 arm spines at d.d. = 21.5 mm; 9-10 arm spines 

 at d.d. 31.5 mm and 10-1 1 arm spines at d.d. = 36.5 mm. 



41. Ophiochaeta hirsuta Liitken, 1869 



See. Clark&Rowe, 1971:88; 127; Sloan et al, 1979: 115;Rowe 

 & Gates, 1995 398. 



Material. 801212B/1 (1), 810425C/2 (1). 



Collection sites. Chetlat, Lakshadweep (Laccadive) Islands; E. 

 Sabang Bay, Pula We, Sumatra. 



Habitat and depth. Coral rubble, 3-8 m. 



Remarks. Sloan et al. (1979) concluded that variation in the 



See. Murakami, 1944: 272 (as Ophiostegastus instratus): 

 A.M.Clark, 1968: 320 (as Ophiostegastus instratus; discussion) 



Material. 810124A/4 (1). 



Collection sites. Ala Gala, Galle, Sri Lanka. 



Habitat and depth. Subtidal rock, 10-15 m. 



Remarks. This specimen, apart from its smaller size and fewer 

 naked disc plates, accords so well with Murakami's (1944) descrip- 

 tion of Ophiostegastus instratus that its identity is in no doubt. The 

 species is, however, transferred to the genus Ophiodyscrita H.L. 

 Clark, 1938 (type-species O. acosmeta H.L. Clark), with 

 Ophiostegatus Murakami, 1944 (of which instratus is the type- 

 species) reduced to a junior synonym of Ophiodyscrita. The 

 distinctness of two genera has been questioned by A.M. Clark 

 (1968) and Guille & Vadon (1985) on the grounds of variation of 

 granulation with increased specimen size. Tabulation of measure- 

 ments (Table 1 ) taken from original species descriptions and similar 

 details of the specimens from Sri Lanka, shows an interesting 

 picture. From this table it becomes apparent that only two species 

 can be recognised: a) Ophiodyscrita instratus (Murakami, 1 943)(d.d. 

 = 7 mm) of which the larger Ophiostegastus novaecaledoniae Guille 

 & Vadon (d.d. = 9-1 1 mm) is a synonym, being an extreme form of 

 instratus in which many disc plates, including the radial shields, 

 have become prominent (convex) and naked of granules; this species 

 possesses supplementary oral shields (granule covered in small 

 specimens < 7 mm d.d.) and b) O. acosmeta H.L. Clark (d.d. - 5 

 mm) with which O. pacifica (Murakami, 1943)(d.d. 4 mm) and 

 Ophiostegastus compsus A.M. Clark (1968) type locality Bahrain 

 (d.d. = 8-10.5 mm) appear to be conspecific. O. acosmeta has an 

 even covering of granules over the disc which are gradually lost only 

 from the oral shields (as in the type of acosmeta; d.d. = 5 mm) and 

 adoral plates (as in the type series of compsus; d.d. = 8-10.5 mm; 

 though A.M. Clark (1968) does note that the largest paratype of 

 compsus (d.d. = 10.5 mm) has a small bare patch dorsally at the base 

 of 4 of the arms). Supplementary oral shields are absent from 

 compsus, according to A.M. Clark, and are not recorded for either 

 acosmeta or pacifica. In both instratus and acosmeta, as recognised 

 herein, it is clear that arm spine number increases with size. 



There is clearly insufficient justification for recognising 

 Ophiodyscrita and Ophiostegastus as, separate genera on the basis of 

 the extent of disc granulation, for it is clear (see Clark & Rowe, 

 1971) that such differences occur between species included within 



