Volume 14, Issue 2, 14 April 2008
Volume 14, Issue 2 – 14 April 2008
John E. Randall and Fenton Walsh: A pictorial review of the Indo-Pacific labrid fish genus Pseudocoris, with description of a new species from the Coral Sea, pp. 45-58
Pseudocoris aequalis is described as a new species of labrid fish collected from 8-15 m depth at Holmes Reef in the Coral Sea. The description is based on six specimens, four as terminal males, 100-112 mm SL, and two as males in the initial phase, 82 and 89 mm SL. The new species is distinct in lacking an elevated anterior part of the dorsal in the terminal-male phase, and the color pattern of both adult phases. Color photographs are provided of the juveniles, initial-phase, and terminal males of the five other species of the genus, with notes on their distribution. Pseudocoris aurantiofasciata is recorded for the first time for Australia, based on a terminal male collected at Holmes Reef.
Holotype of Pseudocoris aequalis, QM I.38118, terminal male, 112 mm SL, Holmes Reef, Coral Sea. Aquarium photo by F. Walsh
Edward O. Murdy: Trypauchenichthys larsonae, a new species of amblyopine goby from Australia (Gobiidae: Amblyopinae) with a key to the species in the genus, pp. 59-68
The Indo-West Pacific gobiid genus Trypauchenichthys is defined and revised. Trypauchenichthys is unique within the Amblyopinae in having the pelvic fins separate (not joined by a connecting membrane). Trypauchenichthys comprises three species: T. larsonae n. sp., known only from the Northern Territory, Australia; T. sumatrensis found in the Strait of Malacca with a reported occurrence in India, and T. typus with specimens known only from the type locality in western Borneo and reports from Thailand, the Philippines, Sarawak, and the Riau Archipelago, Indonesia. A key to species is provided. Figures and descriptions of each species are also given. Putative relationships of the genus are discussed.
Trypauchenichthys larsonae n. sp. (holotype) from the Northern Territory Australia (NTM S. 12491-005). Close-up of head showing smooth frontal crest
María Cristina Oddone, Gonzalo Velasco and Getulio Rincon: Occurrence of freshwater stingrays (Chondrichthyes: Potamotrygonidae) in the Uruguay River and its tributaries, Uruguay, South America, pp. 69-76
Four records of potamotrygonids in the Uruguay River and its tributaries in Paysandú, Uruguay are reported in this paper. The first one was a specimen caught in 1934, of undetermined sex and weighing 120 kg and with a disc width of ca 150 cm. The second specimen, caught in 1998, was also of undetermined sex; it weighed 50 kg total weight and its disc width measured 103 cm. The third specimen was caught in 2001; it was an adult male, weighed 114 kg total weight and its disc width measured ca 110 cm. The fourth one, caught in 2004, was a female, 11 kg in total weight and with a disc width of 80 cm. According to the size and general description, specimens were identified as Potamotrygon brachyura, to date the only potamotrygonid confirmed for Uruguay.
Specimen of Potamotrygon brachyura caught in 2004
James K. Dooley and Lizandra Jimenez: Hoplolatilus luteus Allen & Kuiter, 1989, a junior synonym of H. fourmanoiri Smith, 1964 (Perciformes: Malacanthidae), based on morphological and molecular data, pp. 77-84
Yellow body and caudal fin coloration were the principal characters used to describe Hoplolatilus luteus. Both live observations and preserved specimens of H. fourmanoiri have shown yellow colour pattern variation. Ontogenetic and distributional variation in coloration have been seen in other species of tilefish including Hoplolatilus and Malacanthus. During a week of aquaria observations, the ventral body, head and tail became somewhat darker in H. luteus, shortly thereafter the fish died. It is speculated that a colour change in H. luteus may occur at around 90-105 mm SL. Distinctive subgeneric characters formerly found in H. fourmanoiri and the closely related H. oreni are also found only in H. luteus. Mitochondrial and nuclear DNA analysis between H. fourmanoiri and H. luteus showed identity values of (99%) 587/588 bp and (99%) 792/786 bp for 16S and RAG2 nucleotide sequences, respectively. Phylogenetic analysis of the 16S gene with bootstrapping (1000 replicates), neighbour joining (NJ), and maximum parsimony (MP) analysis always resulted in H. fourmanoiri and H. luteus being shown as terminal sister taxa. Hoplolatilus luteus should be considered a junior synonym of H. fourmanoiri based upon morphological and molecular data.
Live aquarium coloration of a 103 mm SL individual of Hoplolatilus luteus from Bali, Indonesia. Photo by J. K. Dooley
Maroof A. Khalaf and Friedhelm Krupp: A new species of the genus Symphysanodon (Perciformes: Symphysanodontidae) from the Gulf of Aqaba, Red Sea, pp. 85-88
A new species of slopefish, Symphysanodon disii n. sp., is described on the basis of one specimen, 165 mm standard length (SL), collected off the coast of Aqaba, Jordan, Gulf of Aqaba, Red Sea. It is characterised by the following combination of characters: 10 dorsal soft rays, 7 anal soft rays, 50 tubed scales in the lateral line and 12 + 25 = 37 gill rakers on the first gill arch. Body relatively deep (32% of SL); first pelvic ray only slightly produced, not extending to anus; pectoral fin reaching a vertical through base of last dorsal spine; depressed anal fin length 32% of SL; caudal fin deeply forked, both lobes produced into filaments. This is the first record of the family Symphysanodontidae from the Red Sea. Morphologically, the new species is most closely related to the yellowstripe slopefish Symphysanodon katayamai, which is widely distributed in the Central Pacific.
Freshly collected holotype of Symphysanodon disii from Aqaba, SL 165.3 mm, MSSA 64-20/1. Photo by M. A. Khalaf
John E. Randall and Toshiyuki Suzuki: Three new species of dartfishes of the gobioid genus Ptereleotris from the western Pacific, pp. 89-100
The dartfish Ptereleotris brachyptera is described as a new species from eight specimens from Ngargol Island, Palau, and one from Majuro Atoll, Marshall Islands, from lagoons on silty sand and rubble substrata in 20 to 38 m depth. The type specimens, 39.1 to 58.2 mm SL, were first believed to be subadults of P. microlepis or P. hanae until mature fish were found in the series. Ptereleotris brachyptera differs from P. microlepis in having fewer dorsal and anal rays, a more slender body, and a red instead of black bar at the pectoral-fin base. It differs from P. hanae in its very low first dorsal fin and lacking a dark purplish gray stripe on the lower side. It differs from both species in its smaller size and rounded instead of pointed corners on the caudal fin. Ptereleotris crossogenion is described from a single female specimen, 40.7 mm SL, collected from silty sand and rubble in 27 m depth in the lagoon of Madang Province, Papua New Guinea. It is most similar to P. brachyptera, differing in having a fringe of slender papillae along the lower jaw, a deeper body, narrower interorbital space, and in color. Ptereleotris kallista is described from two male specimens, 70 and 85 mm SL, from the aquarium trade in the Philippines. It is a close relative of P. uroditaenia, differing in having a broader interorbital space, longer dorsal spines, and in color, especially a continuous submarginal black band in the caudal fin, compared to two separate converging black bands in P. uroditaenia.
Holotype of Ptereleotris uroditaenia, AMS I.18728-001, 69 mm (after Randall and Hoese, 1985). Drawing by Nancy R. Halliday