Volume 8, Issue 3, June 2004
Volume 8, Issue 3 – June 2004
Carlos A. Rangel, João Luiz Gasparini, and Ricardo Z. P. Guimarães: A new species of combtooth blenny Scartella Jordan, 1886 (Teleostei: Blenniidae) from Trindade Island, Brazil, pp. 89-96
Uma nova espécie de Scartella é descrita para a Ilha da Trindade (20°30’S, 29°20’W), formação vulcânica distante cerca de 1160 km da costa leste do Brasil. A nova espécie difere das suas congêneres do Atlântico pela seguinte combinação de caracteres: corpo e cabeça com pequenas manchas negras, modalmente 14 raios dorsais segmentados, modalmente 16 raios anais segmentados e modalmente 23 vértebras caudais. Essa espécie é a quinta espécie de Scartella reconhecida para o Oceano Atlântico.
Close-up of the head of Scartella poiti n. sp., photographed in an aquarium. Photo by J. L. Gasparini
David Lecchini and Jeffrey T. Williams: Description of a new species of damselfish (Pomacentridae: Chromis) from Rapa Island, French Polynesia, pp. 97-102
A new species of pomacentrid fish recently discovered at Rapa Island, Austral Archipelago (French Polynesia), is described. Specimens were collected during a collaborative marine biodiversity survey of Rapa from October to December 2002. Chromis planesi is described from six specimens, 93.6-101.8 mm SL, captured on the outer reef slope at depths of 50 to 54 m. The new species is distinguished from most described species of Chromis by the following combination of characters: dorsal rays XIV,12-13; anal rays II,12-13; pectoral rays 20; tubed lateral line scales 17; total gill rakers 27-30; axil of pectoral fin black; eye-sized bluish white spot (fades and darkens rapidly after death) on body at bases of posteriormost 6 to 8 segmented dorsal rays. Only four species of Chromis (C. fumea, C. notata, C. verater, and C. struhsakeri) have overlapping counts, a black pectoral axil, and the white spot dorsoposteriorly on body as described above for C. planesi. Chromis planesi is easily distinguished from all four of these species by its distinctive colour pattern: yellowish body with nine stripes, each composed of a series of small blue dots, extending from the gill opening to the caudal fin base; pectoral and caudal fins yellow; and pelvic and anal fins dark brown to black. Among the Chromis species with 14 dorsal spines, the colour pattern of C. planesi is most similar to the those of C. meridiana and C. struhsakeri. Chromis meridiana lacks the blue stripes on the body and has a more slender body (body depth (BD) 2.1-2.3 in standard length (SL) versus BD 1.9-2.1 in SL for C. planesi). Chromis struhsakeri differs in lacking blue stripes, lacking yellow fins, having the white spot extending anteriorly from the top of the caudal peduncle only to about the base of the last dorsal segmented ray, and having a deeper body (BD 1.8-1.9 in SL). This distinctive new species is known only from seven specimens (one sacrificed for genetic sampling) collected on the deep outer reef at Rapa Island.
Chromis planesi, holotype, 97.6 mm SL, Rapa Island. Colour when fresh. Photo by J. T. Williams
Wilson J. E. M. Costa: Rivulus simplicis n. sp. (Cyprinodontiformes: Rivulidae): a new killifish from the coastal plains of south-eastern Brazil, pp. 103-108
Rivulus simplicis sp. n., de uma pequena baixada costeira isolada do sudeste do Brasil, é descrita. Ela pertence ao grupo de espécies R. santensis, que também inclui R. depressus, R. haraldsiolii, R. janeiroensis, R. luelingi, R. nudiventris e R. santensis, e é diagnosticado entre rivulídeos por unicamente possuir o processo ventral do osso angulo-articular curvo. Rivulus simplicis difere de outras espécies do grupo R. santensis por possuir um padrão de colorido distinto de flanco e de nadadeira caudal em machos, e por uma combinação de características morfológicas, incluindo elevado número de raios da nadadeira caudal e posição anterior da origem da nadadeira
Rivulus simplicis, UFRJ 5940, male, holotype, 27.1 mm SL (one day after collection); Brazil: Rio de Janeiro: Parati. Photoby W. J. E. M. Costa
Alexei M. Orlov: Migrations of various fish species between Asian and American waters in the North Pacific Ocean, pp. 109-124
Until now, the continental slope of the Bering Sea was considered to be the only route by which typical American fishes or their pelagic eggs or larvae could reach Asian coasts. These include Pacific halibut Hippoglossus stenolepis, shortraker rockfish Sebastes borealis, arrowtooth flounder Atheresthes stomias, rex sole Glyptocephalus zachirus and sablefish Anoplopoma fimbria. Recent studies have shown that exchange between Asian and American fish populations takes place along the Kuril and Aleutian Islands. Due to recent climatic changes, some species have extended their ranges from the Aleutians to the Kuril Islands and as far as south-eastern Kamchatka (northern rockfish Sebastes polyspinis, dusky rockfish Sebastes ciliatus, arrowtooth flounder, and rex sole). Some species from the Aleutian Islands, described earlier, were recently found to be abundant or common in the Pacific waters off the Kuril Islands. These included blacktip snailfish Careproctus zachirus, longfin Irish lord Hemilepidotus zapus, scaled sculpin Archaulus biseriatus, sponge sculpin Thyriscus anoplus, and roughskin sculpin Rastrinus scutiger. In Aleutian waters these species are very rare and mostly represented by small, immature specimens, whereas adults are very common off the Kurils. It is suggested that the pelagic eggs or larvae of these species may be carried by the waters of the Western Pacific Gyre from the Kuril Islands to the Aleutians.
Scheme of distribution of sablefish, Pacific halibut, arrowtooth flounder, rex sole, and dusky rockfish from the eastern to the western Bering Sea viathrough active migration and range extension of adults, or by the transfer of pelagic fry by currents
Wilson J. E. M. Costa and Dalton T. B. Nielsen: Simpsonichthys carlettoi (Cyprinodontiformes: Rivulidae) a new annual fish from the Rio São Francisco basin, north-eastern Brazil, pp. 125-130
Simpsonichthys carlettoi, um peixe anual coletado nas várzeas do alto rio das Rãs, bacia do médio rio São Francisco, nordeste do Brasil, é descrita. Ela parece ser streitamente aparentada a S. magnificus e S. picturatus, por todas as três espécies possuirem os mesmos padrões de colourido derivados de nadadeiras ímpares e peitoral em machos. A nova espécie difere de S. magnificus e S. picturatus por possuir nadadeiras dorsal e anal terminando em ponta e pela ausência de margem negra nas nadadeiras ímpares de machos.
Simpsonichthys carlettoi, UFRJ 5945, male, wild paratype, about four months before preservation, about 30 mm SL; Brazil: Bahia: Guanambi. Photo by A. Carletto
Philippe Béarez, Jean-Thomas Bujard, María-Cecilia Terán and Roberto Campoverde: First record of two rocky reef fishes from mainland Ecuador: Halichoeres chierchiae (Labridae) and Ostracion meleagris (Ostraciidae), pp. 131-134
Two reef fishes are recorded for the first time from Ecuador. Both have been captured over rocky bottoms covered with gorgonians, along the coast of central-south Ecuador. The previous southernmost distribution limits known were Colombia or the Galápagos Islands for Halichoeres chierchiae, and Panama or Galápagos for Ostracion meleagris. The question of their origin is mentioned.
Terminal phase male Halichoeres chierchiae at Bajo Cope, accompanied by a juvenile H. dispilus. Photo by F. Idrovo
John E. Randall and Gerald R. Allen: Gomphosus varius x Thalassoma lunare, a hybrid labrid fish from Australia, pp. 135-139
An unusual labrid fish photographed and collected off Cassini Island, Western Australia is documented as the hybrid Gomphosus varius x Thalassoma lunare. A second example of the same hybrid was observed on the Great Barrier Reef (not photographed or collected), and one of Gomphosus varius x Thalassoma duperrey was observed at the island of Hawaii (also not photographed or collected).
Gomphosus varius x Thalassoma lunare, Cassini Island, Western Australia. Photo by G. R. Allen