Identity and distribution of southern African sciaenid fish species of the genusUmbrina

Abstract

robinsoni the oblique stripes are thin, wavy, white lines; in U. canariensis the oblique stripes are thicker, nearly straight and brown; U. robinsoni also lacks the triangleshaped mark on the outer operculum and the dark pigmentation of the inner operculum that is found on U. canariensis. Spatial analysis of South African specimens collected with a variety of gear revealed U. robinsoni to be a shallow-water species found from the surf-zone to 40m, whereas U. canariensis occurs predominantly from 40 to 100m depth. Although both species occur throughout the South African eastern seaboard, U. canariensis is most common west of the Kei River, where the shelf is wider. Examination of three specimens of U. steindachneri Cadenat 1950 confirmed the presence of a fourth sub-Saharan Umbrina species that is limited to tropical West African waters from Senegal to Angola. U. steindachneri differs from the other African Umbrina in having a high number of soft dorsal rays (28-29), a greater 3rd dorsal spine length (25-27% SL) and a very pronounced and convoluted striping pattern on the flanks.

Twenty-three new records of commercial fish species (Actinopterygii) from the Socotra Archipelago (north-western Indian Ocean)

“…The observed individuals match the description of Umbrina robinsoni given by Hutchings and Griffiths (2005). A pair of individuals was photographed under water above a silty sand bottom in an area mixed with rocks at Ras Bidou, western part of Socotra Island, at a depth of 14 m. The species is known to usually inhabit open sand areas, but also coral and rocky reef areas, at depths of 1-40 m. Hutchings and Griffiths (2005) resurrected U. robinsoni from synonymy of U. ronchus and noted that the latter can be distinguished by an almost straight dorsal profile of the head between orbit and nape, then steeply convex above preopercle, a longer distance between nostril and anterior margin of orbit (11.8-12.8 in head length versus 14.5-41.5 in head length in U. robinsoni) and by lacking a pale vermiculate pattern. Polynemidae Rafinesque, 1815 Polydactylus plebeius (Broussonet, 1782) Striped threadfin (Fig.…”

Selection of landmarks and semilandmarks in fishes for geometric morphometric analyses: a comparative study based on analytical methods

“…The isolated location of Trigla lucerna in morphospace 3 reinforces this assertion, as it presents an extremely extended pectoral fin with the first three rays transformed, involved in locomotion, substrate lodging or feeding strategies (Jamon et al 2007). Moreover, fishes with presence of sensorial chin barbels used for stimuli reception and finding of food items Aguirre 1997, Hutchings andGriffiths 2005), such as Mullus spp. and Umbrina spp., were also slightly separated from the main group of Perciformes in relation to the morphospace.…”

Population structure and morphology of South African deep‐water parapagurid hermit crabs

“…Door spread was 60–75 m, mouth opening 3–4 m vertical and 20–29 m horizontal, and the footrope was constructed from rubber discs (Atkinson, Leslie, et al, ). Mesh size was 110 mm on the wings and 75 mm in the cod end, which had a 25‐mm mesh liner (Atkinson, Field, & Hutchings, ; Hutchings & Griffiths, ). The main purpose of these demersal research trawl surveys is to assess demersal fish species along the South African coast primarily to inform decision‐making and resources management (see Atkinson, Field, et al, for details).…”