Abstract
Bedotia madagascariensis Regan 1903, type species of the genus and B. geayi Pellegrin 1907 are redescribed from recently collected topotypical material. The two species differ significantly with respect to their life colors, the lengths of the head, snout, caudal peduncle and bases of the second dorsal and anal fins as well as their second dorsal and anal fin ray counts. The aboriginal range of B. madagascariensis comprises eastward flowing streams from the Ivoloina River southward to Manambolo Creek inclusive of small streams flowing into the coastal lakes of the Pangalanes system situated between them, where it occurs up to an altitude of 30 m above sea level. A naturalized population is present in the westward-flowing Betsiboka drainage. Bedotia geayi is only known from the eastward-flowing Mananjary River, where it can be found in small streams between 300 m and 600 m above sea level. A second species of Bedotia from the Rianila basin is described. Bedotia leucopteron sp. nov. is found in shaded streams between 100 m and 850 m above sea level. The wide, iridescent white margins of the unpaired fins taken in combination with a melanophore pattern consisting of small, irregular black spots stochastically distributed over the flanks rather than a distinct midlateral band differentiate living individuals from all known congeners. Data on the natural history and conservation status of all three species are presented.
References
Arnoult, J. (1953) Un poisson d’ornement malgache: Bedotia geayi. Naturaliste Malgache, 5, 225–228
Arnoult, J. (1959) Poissons des eaux douces. Faune de Madagascar, ISRM, Tananarive, 10, 1–169.
Kiener, A. (1963) Poissons, pêche et pisciculture à Madagascar. Publcation du Centre Technique Forestier Tropical (24), 1–244.
Kottelat, M. (1990) Sailfin silversides (Pisces: Telmatherinidae) of Lakes Towuti, Mahalona and Wawotona (Sulawesi, Indonesia) with descriptions of two new genera and two new species. Ichthyological Exploration of Freshwaters, 1, 35–54.
Leviton, A.E., Gibbs R.H. Jr., Heal, E. & Dawson, C.E. (1985) Standards in herpetology and ichthyology: Part I. Standard symbolic codes for institutional resource collections in herpetology and ichthyology. Copeia, 1985(3), 802–832.
Pellegrin, J. (1907) Liste des poissons recueillis à Madagascar par M. F. Geay. Description d’une espèce nouvelle. Bulletin du Musée Nationale d’ Histoire Naturelle, 30, 201–206.
Pellegrin, J. (1914) Sur une Athérinidé nouveau de Madagascar appartenant au genre Bedotia. Bulletin de la Societé Zoologique de France, 39, 178–180.
Pellegrin, J. (1932) Athérinidé nouveau de Madagascar appartenant au genre Bedotia. Bulletin de la Societé Zoologique de France, 57, 84–86.
Pellegrin, J. (1933) Les poissons des eaux douces de Madagascar et des îles voisins. Mémoires de l’Académie Malgache (Tananarive) 14, 1–224.
Regan, C.T. (1903) Descriptions de poissons nouveaux faisant partie de la collection du Musée d’Histoire naturelle de Genève. Revue Suisse de Zoologie, 11, 413–418.
Regan, C.T. (1920) Freshwater fishes from Madagascar. Annals and Magazine of Natural History, (9)5, 419–424.
Reinthal, P.N. & Stiassny, M.L.J. (1991) The freshwater fishes of Madagascar: a study of an endangered fauna with recommendations for a conservation strategy. Conservation Biology, 5, 231–243.
Sparks, J.S. (2001) Bedotia masoala, a new species of atherinoid rainbowfish (Teleostei: Atherinoidei) From the Masoala Peninsula, northeastern Madagascar. Copeia, (2), 482–489.
Sparks, J.S. & Rush, L.M.R. (2005) A new rainbowfish (Teleostei: Melanotaenioidei: Bedotiidae) from the southeastern highlands of Madagascar, with comments on the biogeography of Bedotia. Zootaxa, (1051), 39 - 45.
Sparks, J.S. & Smith, W.L. (2004) Phylogeny and biogeography of the Malagasy and Australasian rainbowfishes (Teleostei: Melanotaenioidei): Gondwanan vicariance and evolution in freshwater. Molecular Phylogenetics and Evolution, 33, 719–734.
Stiassny, M.L.J. (1990) Notes on the anatomy and relationships of the bedotiid fishes of Madagascar, with a taxonomic revision of the genus Rheocles (Atherinomorpha: Bedotiidae). American Museum Novitas, (2979), 1–33.
Stiassny, M.L.J. and I. J. Harrison. (2000) Notes on a small collection of fishes from the Parc National de Marojejy, northeastern Madagascar, with a description of a new species of the endemic genus Bedotia (Atherinomorpha: Bedotiidae). In: S. M. Goodman (Ed.) A Floral and Faunal Inventory of the Parc National de Marojejy, Madagascar with Reference to Elevational Variation. Fieldiana (Zoology), (97), 143–156.