Aseraggodes Kaup, 1858

Randall, John E., 2005, A review of soles of the genus Aseraggodes from the South Pacific, with descriptions of seven new species and a diagnosis of Synclidopus., Memoirs of Museum Victoria 62 (2), pp. 191-212 : 193-194

Aseraggodes Kaup, 1858

Aseraggodes Kaup, 1858: 103 . Parachirus Matsubara and Ochiai 1963: 93 (type species, Parachirus xenichus Matsubara and Ochiai, 1963 opening by original designation and monotypy).

Type species. Aseraggodes guttulatus Kaup, 1858 , by subsequent designation of Jordan and Evermann, 1898.

Diagnosis. Dorsal rays 58–79; anal rays 39–61; caudal rays typically 18 (usually 14–16 branched in adults); no pectoral fins; pelvic rays normally 5; lateral-line scales 39–96 (including those extending onto head); no gill rakers; abdominal vertebrae 10 (including the first vertebra, not counted by some authors, very narrow, the neural spine slender and short, not extending above cranium); total vertebrae 33–40; first two dorsal pterygiophores joined to a thicker bone (termed the erisma and counted as the first pterygiophore, though branched distally to support the first two dorsal rays), its origin between second neural spine and cranium, 7–16 dorsal pterygiophores anterior to fourth neural spine; body an elongate oval, the depth 2.0– 2.8 in SL, and very thin; eyes on right side, elevated, separated by a narrow scaled space; upper eye in advance of lower eye (rarely directly above); caudal peduncle, if present, very short; scales small, ctenoid (except cycloid lateral-line scales); a straight lateral line midlaterally on both sides, with a short anterodorsal branch on blind side; no prominent pore at base of dorsal and anal rays; gill membranes united, free from isthmus, the lower part of head scaled over from ocular to blind side; mouth ventral and small; jaws strongly curved; a band of villiform teeth on blind side of jaws; two nostrils on each side, the anterior nostril of ocular side tubular, but not longer than eye diameter; posterior nostril of ocular side a narrow opening in labial groove before lower eye; dorsal fin originating anteriorly on snout, the first ray not prolonged; caudal fin rounded to slightly pointed, not broadly connected by membrane to dorsal and anal fins; pelvic fins on ventral edge of body, close together anteriorly, adjacent or with ocular-side fin slightly anterior; anus anterior or ventroanterior to first anal ray. Sciatic part of urohyal forming an angle of about 60–85° to horizontal main part of bone.

Remarks. Kaup (1858: 103) briefly described Aseraggodes guttulatus as a new genus and species, but gave no locality for the holotype, as noted by Günther (1862: 477). Chabanaud (1930b) revised the 15 species of the genus then known. He mistakenly placed A. kaianus (Günther) in the synonymy of A. guttulatus and gave two localities, Kei Islands (Günther’s type locality of kaianus ) and the Maldive Islands. Desoutter et al. (2001) resolved the locality problem by finding the holotype in the Muséum National d’Histoire Naturelle ( MNHN 1246, 79.0 mm SL). Kaup’s original label indicated the specimen as the type and the collection locality as Bourbon (= Réunion).

Kaup wrote in his description of Aseraggodes guttulatus that the height of the body is half the total length. Günther (1862: 477) questioned this in a footnote. Martine Desoutter (pers. comm.) measured the height of the body of the holotype as 3.1 in total length. She confirmed Kaup’s counts of the dorsal and anal rays as 64 and 42, respectively. She also provided the lateral-line scale count of 84 and an x-ray, which indicates a vertebral count of 34, and 14 dorsal pterygiophores before the fourth neural spine.

Matsubara and Ochiai (1963) described Parachirus xenicus as a new genus and species of sole from Japan. In a review of the Soleidae and Cynoglossidae of Japanese waters, Ochiai (1963) separated Parachirus from Aseraggodes by having the dorsal, anal, and pelvic fins slightly branched (as opposed to not branched in Aseraggodes ), the tubular anterior nostril reaching the edge of the lower eye (not reaching in Aseraggodes ), vertebrae 32–33, revised in this paper to 33–34 because the tiny first vertebra is now included in the vertebral count (vs 37–39 vertebrae in Aseraggodes ), about 15 interneural spines (= dorsal pterygiophores) associated with the anterior 4 neural spines, and the pelvic fins attached by membrane to the genital papilla. In a generally favorable review of Ochiai’s publication, Hubbs (1967) pointed out its limitation from dealing mainly with Japanese species. Chapleau (1989) made a study of the anterior dorsal pterygiophores, erisma, and neural spines of 41 species of 26 genera of soleid fishes. He recognized Parachirus as a valid genus; however, he included only four species of Aseraggodes in his study.

This study of Aseraggodes has shown that the dorsal, anal and pelvic fins may be simple or branched (the young of those with branched rays have unbranched rays); the tubular anterior nostril often reaches the edge of the lower eye; the vertebrae vary from 33 to 40; the dorsal pterygiophores anterior to the fourth neural spine vary from 7 to 15; and the pelvic fins may be attached by membrane to the genital papilla (as in A. normani ). Therefore, Parachirus is a synonym of Aseraggodes .