Two New Species of the Clingfish Genus Derilissus (Gobiesocidae) from the Western Atlantic

Abstract

Description.-The body shape is shown in Fig. 1. Body proportions are as follows, with the corresponding proportional measurements in parentheses: head length 33.3-36.6%9 (2.7-3.0), head width 28.6-31.8% (3.1-3.4), body depth 27.1-36.6% (3.3-3.6), and pelvic disk length 23.9-25.2% (3.9-4.3) of standard length; eye length 21.6-23.6,% (4.2-4.6) of head length and 59.2-80.9% (1.2-1.6) of interorbital width; snout length 28.2-36.4% (2.73.5) of head length; caudal peduncle length 28.9-50.0% (2.0-3.4) of caudal peduncle least depth. The fin ray counts are as follows, with the frequency of each count in parentheses: dorsal 7(1), 8(2) with the first dorsal ray unsegmented and fused; anal 7(1), 8(1), 9(1) with two specimens having counts of 7 and 9 not having the first anal ray unsegmented and fused; pectoral (both sides counted) 28(2), 29(3), 30(1); pelvic I, 4(3); principal caudal rays 7 + 7(3). All fin rays in all fins are unbranched. In Fig. 1 the anal fin is shown with seven fin rays, however there is another ray hidden within the skin at the anterior end.