In lieu of an abstract, here is a brief excerpt of the content:

Perspectives on Marine Environment Change in Hong Kong and Southern China, 1977-2001 (ed . B. Morton). Proceedings o f a n Internationa l Worksho p Reunio n Conference, Hon g Kong 21-26 Octobe r 2001. Hong Kong: Hong Kong University Press , 2003. THE NEMERTEAN S O F HONG KONG : THEIR DIVERSITY , ORIGIN S AN D ENDEMIS M Ray Gibso n School of Biological an d Earth Sciences, Liverpool John Moores University , Byrom Street, Liverpool L3 3AF, UK and Per Sundber g Department of Zoology, Goteborg University, P.O. Box 463, SE-405 30 Goteborg, Swede n ABSTRACT Thirty-nine specie s of nemerteans hav e so far been recorded fro m Hon g Kong and its surrounding region , comprisin g 1 1 specie s o f palaeonemerteans , 1 7 specie s o f heteronemerteans, te n specie s o f monostiliferou s hoplonemertean s an d on e specie s whose taxonomic placement cannot be determined. These species are distributed between 28 genera. Although 30 of these taxa (77%) are at present only known from Hong Kong, our knowledge of nemertean zoogeographic distribution is insufficient t o assess whether any, and which, of these may be endemic. INTRODUCTION The geologic and hydrographic complexity o f Hong Kong, a small geographic area of only 103 6 km 2 , ha s give n ris e t o a wide variet y o f intertida l an d sublittora l habitat s and communitie s (Morto n an d Morto n 1983) . The intertidal regio n range s fro m har d (erosional) expose d rock y shores , such a s occur a t the tip of Cap e D'Aguilar, t o sof t (depositional) an d virtuall y land-locke d mudflat s wit h sal t meadow s an d mangrov e communities, as found at Wu Kwai Sha and Deep Bay, respectively. Sublittoral habitats include a variety o f sands , silts an d muds, stony bottoms and , in the easter n regions , with their clean, high salinity, oceanic waters, hermatypic corals from th e Indo-Pacifi c province. Thi s enormou s variet y o f habita t type s harbour s a highly divers e rang e o f 110 R. GIBSON & P. SUNDBERG animal species. The present paper summarises our current knowledge of the nemertean fauna o f Hon g Kong , with particular referenc e t o their diversity , possible origin s an d endemism. NEMERTEAN SPECIE S DIVERSIT Y Until only about ten years ago the nemertean fauna of the region was virtually unknown, despite the fact that these invertebrates are often commo n members of the marine biota. The earliest record of nemerteans fro m Hon g Kong is by Stimpson (1855 ) in his brief account of four new anoplan taxa, all of which he placed in the genus Meckelia (Tabl e 1). H e subsequentl y describe d tw o furthe r species , Cephalonema brunniceps an d Polystemma sinuosum (Stimpso n 1857) . It has onl y bee n sinc e 1990 , however, tha t a significant increas e i n th e numbe r o f specie s fro m th e regio n ha s bee n documente d (Gibson 1990 , 1997a , b; Gibson an d Sundber g 1992 , 1999 ) and 3 9 species hav e no w been recorded from 2 8 genera (Tabl e 2). In his checklist of the world nemerteans, Gibson (1995) listed 250 genera and 1,14 9 species, but som e 2 6 new gener a an d 45 new specie s hav e sinc e been described . Th e recorded Hong Kong nemertean fauna thus represents, respectively, some 10% and 3.3% of the genera and species of the world totals. How do these figures compar e with those available from other parts of the world? Gibbons et al. (1999) record 17 species of marine nemerteans fro m 2,88 1 k m o f coastline , althoug h fou r o f thes e wer e offshor e bathypelagic polystiliferous hoplonemerteans , a group which has not yet been reported from th e Hong Kong region. Gibbons et al. (1999) excluded fro m thei r list 1 1 species of benthi c nemertean s whic h ar e o f dubiou s taxonomi c validity . Th e Sout h Africa n nemertean fauna , however , ha s attracte d ver y littl e attentio n an d mus t be regarded a s poorly known; one benthic species...

Share