Bulletin ofZoological Nomenclature 55(3)September 1998 155 Case 3071 Osphronemus deissneri Bleeker, 1859 (currently Parosphromenus deissneri; Osteichthyes, Perciformes): proposed replacement of holotype by a neotype P.K.L. Ng School ofBiological Sciences, National University ofSingapore, 10 Kent Ridge Crescent, Singapore 119260, Republic ofSingapore (e-mail: [email protected]) Maurice Kottelat Casepostale 57. 2952 Cornol, Switzerland (e-mail: [email protected]) Abstract.The purpose of this application is to clarify the identity of Osphronemus deissneri Bleeker, 1859. the type species ofParosphromenus Bleeker, 1877, a genus of licoricegouramiesfromthefreshwaterandpeatswampsofSoutheastAsiaimportant both in the aquarium trade and as environmental bioindicators. The holotype of O. deissneriis badlydamaged and lacks thecharactersnecessary foridentification. It is proposed that it be replaced with a neotype in order to stabilise the taxonomy of Parosphromenus. Keywords. Nomenclature; taxonomy; Osteichthyes; Perciformes; licorice gouramies; belontiidae; Parospliromenus; Parosphromenus deissneri. 1. In 1801 (p. 116), the nominal genus Osphronemuswas estaWished by Lacepede (spelt La Cepedein the publication)with two species. O. goramy (p. 116. pi. 8, fig. 2) and O. galtus(p. 116). O.—goramywas subsequently designated as the type species by Bleeker (1879, pp. 16-17 for date ofpublication see Lamme, 1975). Cuvier(1829, p. 228) referred to 'Ospliromenusgourami[sic]' Lacepede but he did not mention the original spelling Osphronemus, although two years later (Cuvier in Cuvier & Valenciennes, 1831, p. 377) he explained that the name 'osphromene' had been used byCommerson in an unpublished manuscript, and that Lacepede had published this name as 'osphroneme". 2. Bleeker(1859, p. 376)establishedthespecies Osphromemis[sic]deissneri, and in 1877 (pi. 395, caption offig. 1)established the nominal genus Parosphromenus, with Ospliromenusdeissnerias type species by monotypy. This plateappeared in 1877 and predatestheearliestdescriptionofParo.sphromenusgenerallyquoted in theliterature, i.e. Bleeker, 1879, p. 19 (see Boeseman, 1983, p. 4). 3. The licorice gouramies of Parosphromenus are widely distributed in the freshwater and peat swamps of Southeast Asia, and 11 nominal species are now recognised (Kottelat, 1991; Kottelatetal., 1993). Thesefishes areimportant notonly in the aquarium trade but also as environmental bioindicators (Ng, Tay & Lim, 1994). The taxonomy ofspecies ofParosphromenus is difficult as there are very few 156 Bulletin ofZoological Nomenclature 55(3)September 1998 morphological or meristiccharacterswhichcanbeused to separatetaxa. Adult male specimens are necessary before most ofthe species can be identified with certainty, andeventhentheymustbewellpreservedandideallytheirlivecoloursindicated. The useful diagnostic features are characters such as the structure of the paired and unpaired fins, the body and fin colouration and the colour patterning; these characters are discernible only in well preserved material. Many of the older specimens attributed to species of Parosphromenus are poorly preserved, being twisted, shrunken and/or dried, with their fin rays badly damaged and often frayed mm or broken. Parosphromenus species are typically in the size range 15-20 in standard length, and need to be preserved carefully if good specimens are to be obtained forstudyorlong-termcuration. Furthermore, several nominal specieshave been poorly described, with vague and imprecise type localities and ambiguously & designated type material (see Schaller Kottelat, 1989). 4. Although the species Parosphromenusdeissnerihas been reported frequently in scientific and popular literature, the actual identity of the species has only very recently beenclarified (Kottelat&Ng, 1998). Wehavebeenaware forsometime that several conspicuously different species have been identified as '/*. deissneri' by a number of authors, including ourselves. Parosphromenus deissneri was originally mm described by Bleeker from a single specimen reportedly 34 in total length from the island ofBanka (now Bangka), offeastern Sumatra, Indonesia. The species has notuntilrecentlybeenreportedfrom Bangkasinceitsoriginaldiscovery,andnothing was known about it except from Bleeker's papers. Bleeker's figure (1877, pi. 395, fig. 1) ofthe species is schematic and apparently full-size, and appears to depict a large female. The colours are faded and not useful except for confirming the generic identification of recent material, since preserved females of nearly all species of Parosphromenus have the same colour pattern. It cannot be determined whether the colour was based on a fresh or preserved specimen and whether it was accurate. 5. We recently obtained fresh material ofParosphromenus from various localities on Bangka, including Sungai Baturussa, the stream running through Baturussa which is the type locality of Parosphromenus deissneri. Our study of this material showsthattwo speciesoccuron Bangka, the adult males ofeach beingdistinguished by the form of their caudal fins and live colouration. The presence or absence ofa filamentous median caudal-fin ray allows us to identify large adults of both sexes. One ofthe two species is certainly Parosphromenus deissneri and we have described the second asa newspecies, P. hintan (Kottelat& Ng, 1998, p. 265, fig. 3). Although the two species were not collected together, the close proximity of their localities (only a few kilometres apart) suggests that both species will probably be found together once more detailed sampling is conducted throughout the island. 6. Examination of the holotype of Parosphromenus deissneri in the Nationaal Natuurhistorisch Museum in Leiden shows that it is completely discoloured and in relatively poor condition, being shrunken and with all its fins damaged; the taxonomically important caudal fin is completely missing. The condition of the caudal fin and its rays was not described by Bleeker and cannot be determined with certainty from his 1877 figure (pi. 395, fig. 1). One interpretation of this figure is that it is accurate and shows the median caudal-fin ray unbranched and somewhat narrower than the others. Alternatively, the figure is not accurate and the other rays, while appearing thicker, are not depicted as being branched, which . Bulletin ofZoological Nomenclature 55(3)September 1998 157 they should be. Our conckision is that the holotype of Parosphromeims deissneri possesses no characters by which it can be identified with any ofthe known species ofthe genus. 7. We are currently completing a revisionary study of the genus, in which the identitiesofthree poorlyknown speciesaretobeclarified andatleastsi.\newspecies described. All. at sometimeoranother, havebeen called 'Parosphromenusdeissneri' In addition, we have obtained specimens of the second Bangka species (P. bintan) from Pulau Bintan in the Riau Archipelago, this species being the subject of conservation efforts (Kottelat & Ng, 1998). Ourrevisionary studyis hindered by the absence ofa usable type specimen for Parospbromemis deissneri. As pointed out in para. 6abovethee.xtantholotypepossessesnousefulcharacters, andcouldbelongto P. bintan or even to any of the other taxa from nearby islands. Considering the confused taxonomic history of the group, we believe that continued uncertainty about the holotype of Parosphromenus deissneri would pose serious problems for future systematic and biological studies on the genus and its members. 8. To ensure taxonomic stability in the genus and its type species we propose under Article 75b(iii) and Recommendation 75E ofthe Code the designation ofan intact fresh specimen as neotype to replace the damaged and unusable holotype of Parosphromenus deissneri. The original type locality, Baturussa, is now a small city where no suitable habitat containing this species could be found. However, the proposed neotypecomesfromvery nearthe originaltypelocality, and certainlyfrom the same hydrographic basin. The proposed neotype is a male specimen (20,2 mm standard length, 27.1 mm total length), collected on 6 March 1993 by M. Kottelat, N. Sivasothi and T. Tan, from Sungai Baturussa basin, 8 km from Pudingbesar on theroadto KampongSimpan, in Bangka. It isdeposited in theZoological Reference Collection (ZRC), National University of Singapore, under the catalogue number ZRC 31377. Colour photographs of the freshly preserved proposed neotype of P. deissneriarepublished in Kottelat &Ng(1998, p. 265, fig. 3)aswell asoflivemale and female specimens ofboth that species and P. bintan. 9. The International Commission on Zoological Nomenclature is accordingly asked: (1) to use its plenary powers to set aside all previous fixations oftype specimens for the nominal species Osphronemus deissneri Bleeker, 1859 and to designate as neotype the specimen ZRC 31377 in the National University ofSingapore; (2) to place on the Official List ofSpecific Names in Zoology the name deissneri Bleeker, 1859, as published in the binomen Osphromenus [sic] deissneriand as defined by the neotype designated in (1) above (specific name of the type species of Parosphromenus Bleeker, 1877). References Bleeker.P. 1859. Negendebijdrage(I)totde kennisdervischfaunavan Banka. Naimirkimdig Tijilsclirifi voor Ncderlwhisdi Imlie. 18: 359-378. Bleeker,P. 1877-1878. Aliasichthvologiquedeshidesorientcdesneerlandaises,vol. 9. Percoides III. 80 pp.. pis. 355^20. Muller.'Amsterdain. Bleeker, P. 1879. Memoire sur les poissons a phar>ngiens labyrinthiformes de Tlnde archipelagique. Naluurkimde VerlumdelingenKoninklijkeAkademie van Wetenschappen!e Amsterdam. 19: 1-56. 158 Bulletin ofZoological Nomenclature 55(3) September 1998 Boeseman, M. 1983. Introduction. Pp. 1-22 in Bleeker, P., Atlas ichthyologique des Indes orienlales neerlandaises. Plates originally prepared for planned tomes XI-XIVpublished here for thefirst time. 22 pp., pis. 421-575. Smithsonian Institution Press, Washington. Cuvier, G. 1829. Le regne animal distrihue d'apres son organisation, pour servir de base a I'hisloirenaturelledesanimauxetd'introductionaI'anatomiecomparee, Ed. 2,vol. 2. xviii, 532 pp. Deterville, Paris. Cuvier, G. & Valenciennes, A. 1831. Histoirenaturelledespoissons, vol. 7, 531 pp. Paris. Kottelat, M. 1991. Notes on the taxonomy and distribution of some Western Indonesian freshwaterfishes, withdiagnoses ofa new genus and six new species (Pisces: Cyprinidae, Belontiidae, and Chaudhuriidae). hhthyological Exploration of Freshwaters, 2(3): 273-287. Konelat,M.& Ng, P.K.L. 1998. Parosphromenusbintan, anewbelontiidfishfromBintanand Bangka islands. Indonesia, with redescription of P. deis.sneri Bleeker, 1859 (Teleostei: Osphronemidae). IchthyologicalExploration oj Freshwaters. 8(3): 263-272. Kottelat, M., Whitten, A.J., Kartikasari, S.N. & Wirjoatmodjo, S. 1993. Freshwaterfishes of Western IndonesiaandSulawesi. 221 pp., 84 pis. Periplus, Hong Kong. Lacepede, B.G.E. 1801. Histoire naturelle despoissons. vol. 3. Ixvi, 558 pp., 34 pis. Plassan. Paris. Lamme, W.H. 1975. CollectedfishpapersofPieter Bleeker, vol. 7. Junk, The Hague. Ng, P.K.L.,Tay,J.B.& Lim,K.K.P. 1994. Diversityandconservation ofblackwaterfishesin Peninsular Malaysia, particularly in the North Selangor peat swamp forest. Hydrobio- logia. 285: 203-218. Sclialler, D. & Kottelat, M. 1989. Betta strohi sp. n., ein neuer Kampflisch aus Siidborneo (Osteichthyes: Belontiidae). Die Aquarien- und Terrarien-Zeitschrift. 43(1): 31-37. Comments on this case are invited for publication (subject to editing) in the Bulletin: they should be sent to the Executive Secretary, I.C.Z.N., c/o The Natural History Museum, Cromwell Road, London SW7 5BD (e-mail: iczn(gnhm.ac.uk).