Resurrection and Redescription of the Southern Dogfish Squalus probatovi (Squalidae), a Valid Species from Angola

Abstract

Squalus probatovi, a medium size dogfish species originally from Angolan waters, is resurrected as a valid species and redescribed herein based on morphological characters. This species has been misidentified with S. megalops, S. acutipinnis and S. blainvillei due to confused and concise original description and lack of comparative scrutiny with congeners on later taxonomic accounts. Squalus probatovi is sympatric with S. acanthias, S. blainvillei, S. acutipinnis, S. lalannei, S. mahia, S. margaretsmithae, and S. bassi in the Eastern Atlantic and Western Indian Oceans. The Southern dogfish is characterized by having body bluish dark grey, head small, dorsal-fin spines short, pectoral fins narrow with free rear tips rounded, and caudal fin with narrow lobes and pointed caudal tips, snout moderately short with prenarial length slightly greater than inner nostril-labial furrow space, dermal denticles tricuspid and rhomboid, and high number of total vertebrae (118–124). It differs from its regional congeners by having origin of first dorsal fin located over vertical traced at origin of pectoral fins (vs. posterior to origin of pectoral fins), and dorsal fins upright and slender at fin web (vs. prone and broad at fin web, except for S. mahia). The taxonomic status of S. probatovi and morphological comparisons with regional and other similar species are discussed. An identification key to species of Squalus that occurs in African waters is also provided.