Brook Silverside

description

Description. Meristics: median lateral scale rows (69 – 71) 72 – 91 (92); scales above midline 8 – 10 (11); scales below midline 8 – 11; peduncle scales 18 – 22; predorsal scales 36 – 48 (49); interdorsal scales (9) 10 – 15; prepelvic scales (22 – 23) 24 – 32; anus-anal-fin scales 3 – 6 (7); postdorsal scales 14 – 20; postanal scales 10 – 16; first dorsal III – V (6); second dorsal I, 8 – 12; pectoral 11 – 13; pelvic 6; anal-fin I, (19) 20 – 26 (27); caudal 16 – 17 (Table 2). Morphometrics: specimens examined 52.7 – 82.5 mm; short head, four times into SL; eye large, 2.5 times into maximum body depth. Body compressed and elongate, maximum body depth six to eight times into SL, ratio of thoracic length to abdominal length greater than two. Premaxillary long, weakly protrusible, curving ventrally midway along length, creating muzzle like snout; terminal mouth, with moderately long, posteriorly curved, pointed, conical teeth. Forked caudal fin; second dorsal and anal fins falcate; anal fin long, extending length from anterior of first dorsal to beyond posterior of second dorsal; pelvic fin extending to anus; first dorsal-fin origin opposite of anal-fin origin; pectoral fin pointed, ex

Silversides of the genus Labidesthes (Atheriniformes: Atherinopsidae)

diagnosis

Diagnosis. Labidesthes sicculus differs from Labidesthes vanhyningi in having the anterolateral process of the post-temporal longer than width of base (vs. shorter than the base: Fig. 5), a midlateral stripe that tapers anterior of the first dorsal fin to a point behind the dorsal insertion of the pectoral fin (vs. maintaining width or expanding anterior of first dorsal fin: Fig. 3), and a ratio of thoracic length to abdominal length greater than 2 (vs. less than 2).

Silversides of the genus Labidesthes (Atheriniformes: Atherinopsidae)

etymology

Etymology. Likely, from the latin sicula meaning small dagger (Scharpf & Lazara 2014).

Silversides of the genus Labidesthes (Atheriniformes: Atherinopsidae)

materials_examined

Material examined. Syntypes: UMMZ 213812, (2), 52 – 53 mm SL, Grosse Isle, Detroit River, Wayne County, Michigan, by M. Miles. Nontypes: Arkansas River drainage: NCSM 4544, NCSM 47064, NCSM 47499, TU 12004, UAIC 1013.05 (2), UF 21983 (1), UF 22016 (2), UT 158.43, UT 158.252. Brazos River drainage: NCSM 36393, TU 91175. Calcasieu River drainage: TU 44611, TU 64284, TU 121912, TU 124813. Cumberland River drainage: AUM 28924 (7), NCSM 29291, NCSM 48033, NCSM 48342, UAIC 12354.01 (2 + 2 c & s), UT 158.13, UT 158.26, UT 158.40, UT 158.42, UT 158.105, UT 158.108, UT 158.110, UT 158.111, UT 158.117, UT 158.134, UT 158.139, UT 158.238, UT 158.273, UT 158.274, UT 158.281, UT 158.285, UT 158.324, UT 158.379. Galveston Bay drainage: TU 61893, TU 61963, TU 62852, TU 66483, TU 67260, UF 29642 (3), UF 29466 (2 c & s). Great Lakes & St. Lawrence River drainage: TU 19209, UAIC 2985.11 (2), UMMZ 117154 (5 + 2 c & s), UMMZ 132001 (5). Homochitto River drainage: AUM 50798, AUM 50799, AUM 50803, AUM 50814, AUM 50822, INHS 90112 (2), TU 7439, TU 46524, TU 76761, TU 83817. Illinois River drainage: AUM 29752 (1), NCSM 47475, UT 158.79. Meramec River drainage: NCSM 30651, UT 158.109. Lower Mississippi Riv

Silversides of the genus Labidesthes (Atheriniformes: Atherinopsidae)