Apristurus

Abstract: Apristurus brunneus, A. kampae, and Parmaturus xaniurus were caught by trawl and longline between Washington and southern California (48°N to 32°N latitude) from June 2001 through October 2004. In females, oviducal gland width increased with TL in all three species but remained within 4 to 6% of TL. Oocyte diameter increased with TL during reproductive development in all species, and continued to increase with size after reproductive maturity was reached. The weight-length relationships differed significantly among species but not between sexes of any species from the eastern North Pacific combined. Using logistic regression, it was determined that total length at 50% maturity (TL50) of A. brunneus males was 514 mm TL and all A. brunneus males were mature at 547 mm TL. Female A. brunneus reached TL50 at 501 mm TL and all female A. brunneus were mature at 581 mm TL. Apristurus kampae males and females reached TL50 at approximately 485 mm TL and 490 mm TL, respectively. Parmaturus xaniurus males reached TL50 at 444 mm TL and females at 501 mm TL. Gravid female A. brunneus were found in all months of the year, but gravid P. xaniurus were found primarily June through September. Adult A. kampae females were found only in July through November and there were gravid females in all these months. Based upon gonadosomatic indices, IG, these species may mate within a defined period of time (April through June); however, A. brunneus appear to reproduce throughout the year and P. xaniurus reproduce within a defined season (approximately July through September).

Abstract: The diets of six species of catsharks (Carcharhiniformes: Scyliorhinidae) caught between Walvis Bay and Cape Agulhas at depths between 50 and 1 016 m were analysed. The most common prey items were teleosts and crustaceans. Lanternfish (Myctophidae) were common in the diets of Apristurus microps, A. saldanha, Apristurus spp. and Holohalaelurus regani, whereas the Cape anchovy Engraulis capensis was preyed on extensively by Scyliorhinus capensis. The most common crustaceans in the diet were Parapagurus spp., Mursia cristimanus and Euphausia lucens. Cephalopods were uncommon prey items, except in A. microps, A. saldanha, Apristurus spp. and H. regani.

Abstract: Egg capsules of four species of the deepwater catshark genera Galeus and Apristurus are described and compared. The egg capsules of G. murinus and A. aphyodes are firstly described from 4 and 9 capsules respectively, collected in the mother's oviducts. Unlike numerous species of the family, their egg capsules do not have prolonged ten- drils. The smallest gravid females of G. murinus and A. aphyodes measure 460 and 490 mm respectively. Their ovipa- rous mode of reproduction was confirmed. There is only one egg capsule per oviduct for both species, indicating they are single oviparous species. Comments are made on the oviparity of the catsharks of these genera. resume. - Les capsules ovigeres des Scyliorhinidae de profondeur de l'Atlantique Nord-Est, avec la premiere descrip- tion des capsules de Galeus murinus et Apristurus aphyodes (Chondrichtyens, Scyliorhinidae). Les capsules ovigeres de quatre especes de Scyliorhinidae de profondeur des genres Galeus et Apristurus sont decrites et comparees. Les capsules ovigeres de G. murinus et A. aphyodes sont decrites pour la premiere fois, respectivement a partir de 4 et 9 capsules prelevees dans les oviductes des meres. Contrairement a de nombreuses especes de la famille, leurs capsules ovigeres ne sont pas prolongees par des vrilles. Les plus petites femelles gravides de G. murinus et d'A. aphyodes mesurent respectivement 460 et 490 mm. L'oviparite de ces roussettes a ete confirmee. Il n'y a qu'une seule capsule ovigere par oviducte pour chacune de ces especes, ce qui indique une reproduction de type simple oviparite. L'oviparite des roussettes appartenant a ces genres est commentee.