The scorpionfish Rhinopias aphanes Eschmeyer from Australia

Three specimens of the scorpaenid Rhinopias aphanes Eschmeyer from the central Great Barrier Reef Province constitute a new record for Australian waters and the first recorded collections outside New Caledonia.These specimens are described and compared with the holotype.Colouration varies among these specimens;individuals may also change colour in captivity,and according to substratum or time of day.Shedding of "skin"(cuticle)occurs at regular intervals of as short as three days. The holotype of Rhinopias aphanes Eschmeyer, 1973,was collected outside the barrier reef off Noumea in 1964.It was originally identified as a specimen of R.frondosa(Gunther)by Whitley(1964)and by Smith(1966). Eschmeyer et al.(1973)erected the species R.aphanes to contain this specimen.This report describes three specimens collected from Australian waters,with notes on colour variation,habitat, behaviour and "skin" shedding. Genus Rhinopias Gill,1905 Rhinopias aphanes Eschmeyer,1973 Rhinopias frondosa(not Gunther):Whitley, 1964:9,pl.2. Rhinopias aphanes Eschmeyer,in Eschmeyer et al.,1973:300•`302,fig.8. Negative synonym:Scorpaena frondosa Gunther, 1891:482•`483,pl.39. The living holotype is shown in Fourmanoir and Laboute(1976). Conde(1976)and Catala (1979)have figured both this specimen and a second example,collected in the same locality in 1973.Fourmanoir(1976)described 3 juvenile specimens of a Rhinopias species collected by midwater trawl near New Caledonia,and suggested these might be young R.aphanes. These are the only published records of this species. Materials and methods Specimen 1(AMS I.22660-001)was collected by the authors on 19.XII. 1980 on the lee side of Davies Reef,central Great Barrier Reef (18•‹51'S,147•‹38'E),at 11m depth.It was kept in the aquarium at the Australian Institute of Marine Science,Queensland,until its death in November 1981.Two further specimens (both registered as collection AMS I.22659-001, here distinguished as"larger"and"smaller") were collected by C.Wallace,D.Agostino and G.Bull in February 1981 on the lee side of Broadhurst Reef,13 km southeast of Davies Reef,at 6 7 m depth.These specimens were kept alive at James Cook University of North Queensland,but died in August 1981.All three specimens have been deposited with the Australian Museum,Sydney(AMS). Methods of measuring and counting follow Eschmeyer(1965,1969). Specimens were measured with calipers following preservation. Description Measurements and counts.Measurements and counts are listed alongside those for the holotype in Table 1,specimen AMS I.22660-001 is shown in Fig.1. When measurements are compared in terms of percent standard length,the holotype and the three Australian specimens are consistent in most characters.Head length,snout length, jaw length and predorsal fin length are proportionally somewhat greater in the holotype than in the Australian specimens.The smallest example(AMS I.22659-001,smaller)is of similar proportions to the larger specimens, except for its fins which are proportionally larger. In scorpaenids,the number of pectoral rays which are branched increases with the size of the fish(Eschmeyer et al.,1973). This is exemplified in R.aphanes:the smallest specimen (AMS I.22659-001,smaller)has no branched