The shark Carcharhinus galapagensis from Salas y Gómez Island, Chile (Chondrichthyes: Carcharhinidae)

نویسندگان

  • Germán Pequeño
  • Sylvia Sáez
چکیده

This shark has been listed among Chilean species based on Randall and Cea-Egaña (1984), who gave a listing of vernacular names for the fishes of Easter Island (Pequeño 1989). Grove and Lavenberg (1997) record having photographed Carcharhinus galapagensis (Snodgrass and Heller 1905) at Salas y Gomez Is. There are no data to our knowledge of anyone examining specimens captured at either Easter Is. or Salas y Gomez Is. The distribution of C. galapagensis is generally discontinuous, including a broad range of distribution in both Atlantic and Pacific oceans, even to Japan (Taniuchi et al. 1985). The present study confirms the presence of this species in this isolated area using specimens caught on the CIMAR-5 Cruise. Both females, were obtained by hook and line fishing at a depth of over 25 m at Salas y Gomez Island (26o 28’ S, 105o 21’ W) on 7 Nov. 1999. One specimen measuring 1200 mm TL (Total length) was numbered IZUA-PM-2144 and the other of 790 mm IZUA-PM-2145, in the Collection of Fishes of the Instituto de Zoología, Universidad Austral de Chile. The mandibles of the specimens were compared with a known C. galapagensis mandible obtained from the California Academy of Sciences (CAS 39607) representing a 126 cm TL male from the Galapagos Islands. There was a high concordance of diagnostic characteristics between our specimens and literature data on C. galapagensis. Among the differences observed, the most notable was the length of the posterior margin of the first dorsal fin which was practically triple that cited by previous authors. The dental formula of our specimens was coincident with that of the mandible observed (CAS 39607). The smaller specimen (a) and larger specimen (b) showed the following dental formulae:

برای دسترسی به متن کامل این مقاله و 10 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Distribution and diet of four species of carcharhinid shark in the Hawaiian Islands: evidence for resource partitioning and competitive exclusion

Competition and predation are both important in structuring the distribution of marine organisms; however, little is known about how competition and predation influence the distribution of elasmobranch fishes. We used data collected from shark control programs conducted between 1967 and 1980, throughout the Hawaiian island chain, to examine the distribution and dietary overlap of the 4 most abu...

متن کامل

Acanthocheilus rotundatus (Nematoda: Acanthocheilidae) from the intestine of shark (Carcharhinus macloti) in Persian Gulf, Iran

In a parasitic study on five Sharks (Carcharhinus macloti) caught from the Iranian coasts of Persian Gulf, two of five sharks appeared to have nematode in their intestine. Using light microscopy, the nematode was identified as Acanthocheilus rotundatus. A. rotundatus  is characterised by 3.3-4.5 cm in length, semithick cuticle, small lips, semicircular and tri-lobed pseudolabia (not offset from...

متن کامل

Isolation and characterization of eight microsatellite loci from Galeocerdo cuvier (tiger shark) and cross-amplification in Carcharhinus leucas, Carcharhinus brevipinna, Carcharhinus plumbeus and Sphyrna lewini

The tiger shark Galeocerdo cuvier (Carcharhinidae) is a large elasmobranch suspected to have, as other apex predators, a keystone function in marine ecosystems and is currently considered Near Threatened (Red list IUCN). Knowledge on its ecology, which is crucial to design proper conservation and management plans, is very scarce. Here we describe the isolation of eight polymorphic microsatellit...

متن کامل

Shark Records from Longline. Fishing Programs in Hawai'i with Comments on Pacific Ocean Distributions

This paper summarizes records from longline fishing programs conducted in Hawai'i between 1959 and 1980. Data from 11 species of sharks (173 individual sharks) are reported and compared with worldwide records. Although much of the data is nearly 30 yr old, the information was never fully utilized and represents the following important findings. The relationship between clasper length and total ...

متن کامل

Extinction of a shark population in the Archipelago of Saint Paul’s Rocks (equatorial Atlantic) inferred from the historical record

Detecting and determining the validity of local extinctions is an important conservation measure in order to uncover management failures. There are quantitative and qualitative methods that estimate extinction probability based on past sighting records. However, because current baselines about species’ abundances and distributions in the sea were mostly established after humans had started affe...

متن کامل

افزودن به منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی راحت تر خواهید کرد

برای دسترسی به متن کامل این مقاله و 10 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2004