|Scientific Name:||Dipturus leptocaudus|
|Species Authority:||(Krefft & Stehmann, 1975)|
|Taxonomic Notes:||Synonym = Dipturus leptocauda Krefft & Stehmann 1975 (Vooren 1997; Menni and Stehmann 2000).|
|Red List Category & Criteria:||Data Deficient ver 3.1|
|Assessor(s):||Rincon, G. & Mazzoleni, R.|
|Reviewer(s):||Kyne, P.M., Cavanagh, R.D., Stehmann, M. & Fowler, S.L. (Shark Red List Authority)|
Until recently, Dipturus leptocaudus was known from only a very small number of specimens caught off southern Brazil. However, recent records from the deepwater trawl squid fishery off Santa Catarina State are thought to be D. leptocaudus, thus this species (predominantly juveniles) is an apparently relatively common component of the bycatch from this fishery. Neonates with yolky bellies and disc widths 17.6 to 20.5 cm were captured, providing evidence of a local nursery ground (400 to 550 m depth) in the area being fished. However, it is highly likely that adults occupy deeper habitats, which are not being trawled (trawlers generally do not operate deeper than 600 m). Indeed, its distribution range on the mid and deep slope along Eastern South America may be much wider than currently known. Studies are required in order to correctly evaluate the impact of the squid fishery on the local population(s). At present since almost nothing is known of its biology and population status, the species is considered Data Deficient, but it must be noted that given its apparent restricted distribution and probable vulnerability to the increasing deepwater squid fishery, it may meet the criteria for Vulnerable in the near future.
|Range Description:||There are only three records of juvenile specimens of this species by Krefft and Stehmann (1975) and Gomes and Costa (2003). These specimens were captured between São Paulo and Santa Catarina States (24° to 29°S and 43°-46°W), Brazil. However, recently captured juveniles and neonates have characteristics that suggest they may belong to this species (author, pers. obs).|
Native:Brazil (Santa Catarina, São Paulo)
|FAO Marine Fishing Areas:||
Atlantic – southwest
|Range Map:||Click here to open the map viewer and explore range.|
|Habitat and Ecology:||
Biology is unknown. However, recently captured neonates had yolky bellies and disc widths of 17.6 to 20.5 cm were taken by the deepwater squid fishery and provide evidence of a local nursery ground (400 to 550 m depth).
Specimens identified as D. leptocaudus in the bycatch of the deepwater squid fishery had squids Illex argentinus in their stomachs. Only juveniles were saved for further studies, but fishermen reported some adults as also present in the catches, although at present the identification of these specimens cannot be verified.
|Major Threat(s):||Bycatch in deepwater squid fishery which trawls for reproductive schools of squid Illex argentinus off Santa Catarina State, Brazil during the winter season (August and September). Studies are required to assess the impact of this fishery, and training is needed given that misidentification with D. chilensis may be confounding accurate recording of bycatch.|
|Conservation Actions:||None in effect or proposed.|
|Citation:||Rincon, G. & Mazzoleni, R. 2004. Dipturus leptocaudus. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 05 July 2015.|