INDIAN OCEAN ECHINODERMS 



79 



Table 1. 



Details of species Ophiodyscrita acosmeta H.L. Clark* and O. instratus (Murakami)* 



Taxon 



d.d. (mm) a.sp. l.a.sp. s.o.s. Granulation (disc) 



Ophiocryptus* 



4.00 



6-5 



1/3 seg. 



_ T 



pacificus Murakami, 1943 











Ophiodyscrita* 



5.0 



8(7) 



1/2 seg. 



_ 7 



acosmeta H.L. Clark, 1938 











Sindbad spec* 



5.3 



6-5 



<l/2 seg. 



+ (granule 

 covered 



Ophiostegastus* 



7.00 



7 



1/3 seg. 



+ (naked) 



instratus Murakami, 1944 











Ophiostegastus* 



8-10.5 



9 



< 1/2 seg. 



- 



compsus A.M. Clark, 1968 











Ophiostegastus* 



9-11 



9-10 



< 1/2 seg. 



+ (naked) 



novaecaledoniae 











Guille & Vadon, 1985 











Complete cover dorsal and ventral 



Complete cover dorsal and ventral except 2 oral shields (Clark & Rowe 



(1971: 135) 

 Complete cover dorsal and ventral except radial plate at base of deach arm. 



each mid marginal plate and ventrally, each of the oral shields 

 Complete except 3 plates at base of each arm; each mid marginal; each oral 



shield and supplementary oral shield 

 Complete except each oral shield and adoral shield (A.M. Clark notes a 



small bare patch as base of 4 arms of one paratype d.d. = 10.5 mm) 

 Many dorsal plates, including radial shields, marginal plates and ventral 



plates including oral, supplementary oral and adoral shields bare of 



granules 



d.d. = disc diameter; a.sp. = number of arm spines; l.a.sp. = length of arm spines; s.o.s. (+/-) = presence/absence of supplementary oral shields. 



the recognised limits of other ophiodermatid genera (e.g. Ophiopeza 

 & Ophiarachnella). Similarly, the occurrence of supplementary oral 

 shields is also a variable character. The recognition of Ophiodyscrita 

 within the family appears, therefore, to rely, more or less solely, on 

 the extension of granulation along the arms. The genus is closely 

 related to Ophiopeza with which it shares the possession of a triangle 

 of 3 plates between the radial shields (see Vail & Rowe, 1989). The 

 record of O. instratus from Sri Lanka greatly extends the known 

 distribution of the species from Japan and New Caledonia (S.W. 

 Pacific). The distribution of the genus, Ophiodyscrita (syn: 

 Ophiostegastus ) is clearly widespread in the Indo-West Pacific 

 region. 



43. Ophiopsammus yoldii (LUtken, 1856) 



| See. A.M.Clark, 1968; 317; Clark & Rowe, 1971:90; 127;Vail& 

 , Rowe, 1989: 277; Rowe & Gates. 1995: 402. 



Material. 810430A/22b (1). 



I Collection SITES. Ug Seukundo, Pula We, Sumatra. 



Habitat and depth. Coral rubble; 9 m. 



Remarks. Nearly half of the disc of this small specimen has been 

 lost leaving the remaining disc (d.d. = c. 6 mm) and three of the 

 original arms, which are also damaged (a.l. = c. 1 7 mm; d.d./a.l. = c. 

 3+ : 1). Arising from the damaged edge of the disc are three new, 

 minute arms at slightly different stages of growth judging by the 

 relative development of the ventral arm plates on each arm. These 

 arms are also damaged but the longest is judged to have been not 

 more than c. 3-4 mm in length. Following Vail & Rowe's (1989) 

 revision of the genus Ophiopsammus, there is no reason for not 

 identifying the specimen from Pula We as O. yoldii, for it appears to 

 match their criteria for the species even though it is of small size. The 

 species is not known to be fissiparous. Although this may be the first 

 observation of fissiparity in O. yoldii, the development of six arms, 

 in this case, may be an unusual response to severe damage, rather 

 than being related to an asexual reproductive strategy. This matter 

 requires further investigation. 



Family OPHIURIDAE 



44. Ophiolepis cincta Miiller & Troschel, 1842 



See. Clark & Rowe, 1971: 90; 129; Clark & Courtman Stock, 



1976: 189; Sloan etal, 1979: 1 15-1 17; Rowe & Gates, 1995: 399. 

 Material. 801212B/1 (1). 



Collection SITES. Chetlat, Lakshadweep (Laccadive) Islands. 

 Habitat and depth. Coral rubble; 8 m. 



Class Echinoidea 



Family CIDARIDAE 



1. Eucidaris metularia (Lamarck, 1816) 



See. Clark & Rowe, 1971: 140; 150; Clark & Courtman Stock, 

 1976: 215; Sloan etal, 1979: 1 1 7 Rowe & Gates, 1995: 195. 



Material. 810426A/4 (1), 810501E/12 (1). 



Collection sites. Rubiah, Ug Seukundo, Pula We, Sumatra. 



Habitat and depth. Coral reef, coral aggregate; 10 & 14 m. 



Family DIADEMATIDAE 



2. Diadema setosum (Leske, 1778) 



See. Clark & Rowe, 1971: 140; 153; Clark & Courtman Stock, 

 1976: 226; Sloan etal., 1979: 118; Price, 1983: 73; Rowe & Gates, 

 1995: 207. 



Material. 801027A/1 (1), 801030A/la,b (4), 810212A/1 (1), 

 8 1 0420 A/ 1 (1), 810420A/4 (1), 8 10426 A/3 (1), 810426B/5 (2), 

 810426B/12 (1), 810427D/5 (1 juvenile), 81 0428D/4 (2), 810501G/ 

 4 (1 juvenile), 8105011/1 (1), 810502D/1 (1, broken). 



Collection sites. Muscat, Oman; Unawatuna, nr Galle, Sri 

 Lanka; Rubiah, Klah, Ug Murung, Ug Tapa Gadja, Ug Seukundo, 

 Pula We, Sumatra. 



Habitat and depth. Subtidal rock, subtidal rock / sand, subtidal 

 rock / coral, coral reef; 0-20 m. 



Remarks. A number of these specimens are juveniles, as small as 

 10 mm h.d., and with banded spines. The characteristic elongate, 

 tridentate pedicellariae of D. setosum (see Clark & Rowe, 1971 ) are 



