Although Chaceon affinis is practically unknown to Canarian fishermen, relatively abundant quantities of deep-sea red crab C. affinis have been found in all trap surveys conducted around the Canary Islands in the last 10 yr, in which waters deeper than 550 m have been examined. From July 1994 to May 1996, monthly samples were taken from north-eastern waters off Tenerife using a variety of trap designs. Crabs were caught at depths ranging from 550 to 1200 m on muddyrocky bottoms. A variety of measurements were taken from each specimen, and most of these showed linear and isometric growth relative to carapace width (CW). Male chela width (ChW) and female abdomen width (AW) did not show such evident allometry as other crab species. Changes in growth of these features, considered as secondary sexual characters, were used to discriminate morphometrically immature crabs from mature crabs, using hierarchical cluster analysis. Different morphometric groups were distinguished, for both males and females, and male ChW and female AW were plotted against CW. Regressions were calculated separately for each cluster to test the discrimination statistically. Morphometric size at maturity was initially estimated and compared with data on gonad stage. This comparison revealed a high correlation in males between morphometric and sexual maturity, which is reached at about 129 mm CW. However, most females become morphometrically mature before their ovaries mature and before copulation (at sizes of ~99, 108 and 113 mm CW, respectively). KEY WORDS: Biology · Maturity · Chaceon affinis · Geryonidae · Canary IslandsResale or republication not permitted without written consent of the publisher

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SUMMARY: Pontinus kuhlii is a Scorpaenidae which forms part of the bottom longline by-catch in the Canary Islands fisheries within setting operations from 200 to 400 metres depth. Information on their biology and on the age determination and growth of the species is very scarce. The main objective of the study was to look at this biological aspect based on 421 specimens caught in the Canarian Archipelago during the period July 1996 and August 1997, 286 of which were male, 130 female and 5 indeterminate. Age was determined through the interpretation of annual growth rings of otoliths and scales, and the results fitted the von Bertalanffy growth function. Otolith sectionings were discarded due to annuli losses caused by the edge structure. The structures used in age interpretation showed numerous false rings that made the process difficult, causing 17% of the cases to be rejected. However, the age interpretations from scales showed less variability in relation to the whole otolith. The ages of the specimens ranged from 6 to 18 years for males and from 6 to 14 years for females. The growth parameters for males were: K= 0.132, L ∞ = 46.7 and t o = 1.74; for females: K= 0.094, L ∞ = 46.3 and t o = 0.05; and for the total: K= 0.095, L ∞ = 52.2 and t o = 1.01.