CHROMIS ALPHA - (RANDALL, 1988)
Actinopterygii (Class) > Perciformes (Order) > Labroidei (Suborder) > Pomacentridae (Family) > Chromis (Genus)
Alpha chromis, Yellow-speckled chromis, Yellow-spotted puller, Yellowspeckled puller, Arufa suzumedai, アルファスズメダイ, 白光鰓魚,
Dorsal spines (total): 13; Dorsal soft rays (total): 12-13; Anal spines: 2; Anal soft rays: 11-13 (usually: 12); Pectoral ray: 16-18; Spiniform caudal ray: 3; Tubed lateral line scales: 14-16 (usually: 15); Gill rakers: 8+21 (7-9 + 19-23); Body depth: 1.8-2.0 in SL; Head length: 3.2 (3.0-3.25) in SL; Snout length: 3.75 (3.5-4.05) in head; Orbit diameter: 2.8 (2.6-3.0) in head; Interorbital width: 2.6 (2.7-2.95) in head; Caudal peduncle depth: 2.0 (1.95-2.3) in head. No auxiliary scales on body. Preopercular margin not serrate. Anterior nostril with narrow fleshy rim, slightly higher posteriorly; Posterior nostril small elongate pore diagonally above and behind anterior nostril near orbit in front of upper margin of pupil. Pores of lateralis system on head small. Free margin of suborbital short, ending below a vertical at front edge of pupil. Max length: 8.5 cm SL. Depth range: 12 - 95 m, usually: 35 - 80 m.
Scales of upper five-sixths Of body and postorbital head with dark brown edges and greenish centres containing one or more yellowish blotches (the blotches yellow on head and anterodorsally on body); Lower sixth of body purplish blue; Narrow dark bar on opercular edge and gill opening above level Of pectoral base; Upper preopercular margin in a dark brown bar; Median fins dark brown except posterior membranes which are clear and outer spinous portion of dorsal fin and Outer anal fin which are orangish brown; paired fins slightly dusky, base of the pectorals dark brown, upper corner with still darker spot.
Chromis: from Greek, chromis = a fish, perhaps a perch.
alpha: from the Greek alphos = white-spotted. As from leprosy, in reference to the pale spots on the head and body. Also the name was chosen because alpha is the first letter of the Greek alphabet. This fish was first diagnosed and illustrated by Gerald R. Allen (1975) who referred to it as Chromis sp. "A".
Original description: Chromis alpha Randall, 1988 - Type locality: Outside reef off western side of Rimatuu Islet, Tetiaroa Atoll, Society Islands, depth 45 meters, 60° slope with rich coral bottom, spear, J.E. Randall, 24 April 1973, female (84.0 mm).
Indo-West Pacific: Christmas and Cocos-Keeling Islands, Indonesia to Philippines, Western Australia, New Caledonia, Papua New Guinea to Micronesia and French Polynesia.
Adults occur in clear lagoon and seaward reefs, usually seen singly or in loose aggregations near caves and ledges. Abundant over branching corals and leeward coasts. Feeds on planktons. Oviparous, distinct pairing during breeding. Eggs are demersal and adhere to the substrate. Males guard and aerate the eggs.
Chromis nigroanalis (Randall, 1988) - Reported from East Africa and Madagascar east to Indonesia.