NEW SPECIES OF OPHIDIASTER 



39 



Four or five actinal plates in each intermediate area, armed with 

 single spines corresponding to the subambulacral spines (Fig. 1 ). 

 Colour (in the dried state) yellowish with faint darker bands. 



In addition to the holotype, there are four paratypes from 

 Amoy, Fujian Province, far to the east of Hainan Strait. These 

 are much larger than the holotype (which was selected for better 

 comparison with the type material of Ophidiaster armatus) and 

 have R 95, 105, 108 and 115 mm. Three of them have 

 pedicellariae on some abactinal plates. 



Four other large specimens (R c. 1 30 mm), from the east side 

 of Hong Kong Island in c. 15 m, studied by A.M.C., show some 

 variation in the extent of the marginal spines, which are most 

 numerous on the inferomarginals and may extend almost to the 

 interradius. 



Remarks. This new species was previously referred to 

 Ophidiaster armatus Koehler, 1910 by A.M. Clark (1982) and by 

 Liao & Clark in 'The echinoderms of southern China' (in press), 

 both references commenting on the unusually large size. During 

 a visit to the Senckenberg Museum by the senior author in 1993, 

 a direct comparison was made between the small Chinese 

 specimen and the three syntypes of O. armatus from the Aru 

 Islands, Indonesia, of similar size. As a result of this 

 comparison, we conclude that the Chinese specimens are 

 specifically distinct, the differences being evident as shown in 

 Table 1. 



The maximum size for Ophidiaster armatus, R 66 mm, was 

 observed by H.L. Clark (1938) in material from Queensland, 

 Australia. 



It is noteworthy that all three syntypes of O. armatus do have 

 some abactinal pedicellariae which Koehler seems to have 

 overlooked, however, the occurrence of pedicellariae is rarely 

 regarded as a character of specific weight in this family. 



The presence of spines on plates other than the 

 adambulacrals, separates Ophidiaster armatus and O. 

 multispinus from the remaining species of the genus Ophidiaster. 



Table 1 Comparison between the two species mentioned. 



Ophidiaster multispinus sp. nov. O. armatus Koehler 



Maximum R 130 mm. Maximum R 66 mm. 



Arms stout, br 1 1 mm at R 60 mm. Arms slender, br 9 mm at R 60 mm. 



Marginal spines fairly conspicuous Marginal spines not at all 

 and more extensive, absent only conspicuous, only present 

 from the first 3-5 plates towards the arm tips 



Proximal adambulacrals with two Subambulacral spine series 

 series of subambulacral spines single throughout 



4 or 5 spinose actinal plates in 

 intermediate area 



No spinose actinal plates 



However, in our opinion, this character is not of sufficient 

 importance to justify a generic distinction, especially as the 

 lesser development in O. armatus provides an intermediate 

 condition. 



REFERENCES 



Clark, A.M. 1982. Echinoderms of Hong Kong, pp. 485-500. In: B.S. Morton & 



C.K. Tseng (Eds) The marine flora and fauna of Hong Kong and southern China. 



(Hong Kong, Hong Kong University Press). 

 Clark, A.M. & Rowe, F.W.E. 1971. Monograph of shallow-water Indo-West Pacific 



echinoderms. London: British Museum (Natural History), ix + 238 pp. 

 Clark, H.L. 1938. Echinoderms from Australia. Memoirs of the Museum of 



Comparative Zoology. Harvard 55: viii + 596 pp. 

 Koehler, R. 1910. Asteries et Ophiures des iles Aru et Kei. Abhandlungen 



Senckenbergischen Naturforschen dem Gesellschaft, 33(3): 265-295. 

 Liao, Y. & Clark, A.M. (in press). The echinoderms of southern China. 



