ABSTRACT
A new species of round stingray, Urobatis pardalis sp. nov., is described from material collected in the Pacific coast of Costa Rica. This new species differs from its congeners by the color pattern of the dorsal surface and by several proportional measurements. A key to all species of the genus is provided.
Nueva especie del género Urobatis (Myliobatiformes: Urotrygonidae) del Pacífico oriental tropical. Una nueva especie de raya redonda con espina, Urobatis pardalis sp. nov., es descrita a partir de material recolectado en las costas del Pacífico de Costa Rica. Esta nueva especie difiere de sus congéneres por el patrón de la coloración dorsal del disco y por varias relaciones de medidas. Se presenta una clave para la determinación taxonómica de las especies del género.
Subject(s)
Skates, Fish/anatomy & histology , Marine Fauna , Aquatic Organisms , Costa Rica , Marine BiologyABSTRACT
Several expeditions in recent years to Isla del Coco have increased the total number of species of fishes known from the island. Several of these species have been described as new endemics (Bussing 1983, 1990, 1991a, 1991b, 1997). During the 1972 R/V Searcher Expedition to Costa Rica several trawl collections were made around Isla del Coco. At five localities in depths between 110 and 180m, 86 specimens of a new species of Peristedion were taken and are described herein. A key to the four species of Eastern Pacific Peristedion is included. Rev. Biol. Trop. 58 (4): 1149-1156. Epub 2010 December 01.
Varias expediciones en años recientes a la Isla del Coco han aumentado el número total de especies de peces conocidas de la isla. Se han descrito varias de estas nuevas especies como endémicas (Bussing 1983, 1990, 1991a, 1991b, 1997). Durante la Expedición R/V Searcher de 1972 a Costa Rica, se hicieron varias recolectas con redes de arrastre alrededor de la isla. En cinco localidades, con profundidades entre 110 y 145m, se capturaron ejemplares de una nueva especie de Peristedion que se describe en este trabajo. Se incluye una clave para las cuatro especies del Pacífico oriental.
Subject(s)
Animals , Fishes/anatomy & histology , Fishes/classification , Costa Rica , Pacific Ocean , Species SpecificityABSTRACT
Astyanax cocibolca, a small filter-feeding species is a new characid species endemic to Lake Nicaragua. It is distinguished from the syntopic Astyanax aeneus by its high gill raker count, slender body, upturned snout, long maxillary bones, conical outer premaxillary teeth, lower number of scales above lateral line, more intense black lateral band, smaller size, and trophic niche partitioning. At present the new species utilizes the open-water habitat at least as a nursery where young can feed on the rich plankton population. Adults feed on copepoda, cladocera, fruits, seeds and algae. The bulk of the adult population presumably resides inshore. Rev. Biol. Trop. 56 (3): 1361-1370. Epub 2008 September 30.
Se describe Astyanax cocibolca, una nueva especie pequeña y planctívora, endémica en el Lago de Nicaragua. Se distingue de la especie simpátrica Astyanax aeneus por su alto número de branquiespinas, cuerpo delgado, hocico inclinado hacia arriba, maxilar serrado en algunos, dientes unicúspides en la fila exterior del premaxilar, menor número de escamas arriba de la línea lateral, banda negra lateral más intensa y tamaño menor.
Subject(s)
Animals , Female , Male , Fishes/anatomy & histology , Fishes/classification , Fresh Water , NicaraguaABSTRACT
An undescribed freshwater fish was recently discovered during a biological inventory of Area de Conservación Guanacaste, northwestern Costa Rica. This new species of Poeciliopsis is closely related to a group of widespread species of small spotted fishes designated as the Poeciliopsis gracilis complex in this study. The complex extends on both versants from southern Mexico to Nicaragua, and with this new finding, extends into Costa Rica. The new species is distinguished from its Central American relatives by its lack of lateral and ventral markings, higher pectoral and caudal-fin counts and more posterior placement of the dorsal fin. Poeciliopsis santaelena is endemic to the Río Potrero Grande, a river whose flow is reduced to just a few pools during the long dry season and flows fully only during very rainy weather. It is just another in a growing list of threatened or endangered species found in this unique peninsular environment. Rev. Biol. Trop. 56 (2): 829-838. Epub 2008 June 30.
Recientemente se descubrió una especie no descrita de pez dulceacuícola durante un inventario biológico en Area de Conservación Guanacaste (ACG) en el noroeste de Costa Rica. Esta especie nueva del género Poeciliopsis tiene un parentesco cercano con un grupo de especies con puntos en los costados ampliamente distribuidas que se designan en este informe como complejo de Poeciliopsis gracilis. El complejo se extiende en ambas vertientes desde el sur de México hasta Nicaragua. La especie nueva se distingue de sus parientes centroamericanos por su falta de manchas negras laterales y ventrales, mayor número de radios pectorales y caudales, y posición más posterior de la aleta dorsal. Poeciliopsis santaelena, especie endémica de un sólo riachuelo intermitente, es una especie más in la lista de especies en peligro que se encuentra en este peculiar ambiente peninsular.
Subject(s)
Animals , Female , Male , Cyprinodontiformes/anatomy & histology , Cyprinodontiformes/classification , Costa Rica , Sex CharacteristicsABSTRACT
Three of four new jawfishes described herein have sexually dimorphic jaws and dichromatic maxillary markings: O. smithvanizi, with a simple nasal cirrus, buccal pigmentation and other traits similar to members of the O. macrognathus group, is known only from Isla del Caño, a continental shelf island off southern Costa Rica; O. fossoris, with a multifid nasal cirrus, a broad dorsal membranous subopercular flap and a black spot on tips of first dorsal-fin spines lives in the Gulf of California and is a sister-species of O. galapagensis, the maxilla of O. walkeri terminates in a flexible scimitar-shaped lamina in adults of both sexes, but is longer in males, the species lacks nasal cirri and is also restricted to the Gulf of California. Opistognathus brochus is a small species with dark speckling on head and body, and several dark blotches along the dorsal fin and two bars on the tail; it is found in moderately deep water on the Costa Rican coast and Gulf of California. Opistognathus mexicanus is placed in the synonymy of O. punctatus. Opistognathus galapagensis, O. rhomaleus and O. fenmutis are recorded for the first time from Costa Rica and a description of the latter is given and an identification key and summary table are provided for all known eastern Pacific species of Opistognathus.
Subject(s)
Animals , Male , Female , Fishes , Sex Characteristics , Costa Rica , FishesABSTRACT
A new hovering goby or dartfish is described from material collected in Mexico, Costa Rica and Panama. It is the only species of the cosmopolitan genus Ptereleotris known from the eastern Pacific. It is distinguished from its Western Atlantic and Indo-Pacific congeners by its low fin-ray counts, prominent median keel on the ventral margin of the head, lanceolate caudal fin with dusky lower half and dusky blue or lavender body in adults.
Subject(s)
Animals , Female , Perciformes/classification , Costa Rica , Mexico , Pacific Ocean , Panama , Perciformes/anatomy & histologyABSTRACT
A list is presented of 242 species of fishes taken in the Golfo de Nicoya, Golfo Dulce and on the Pacific continental shelf of Costa Rica. The specimens were collected using dredges and bottom trawls during December 1993 and February 1994. The Golfo Dulce revealed the lowest diversity with only 75 species represented; 118 species were collected in the Golfo de Nicoya and 129 species in offshore waters. It is presumed that low fish diversity in Golfo Dulce is due to the deep, unproductive waters in that embayment. The checklist includes presence-absence data for each locality