shortsnout chromis

description

(Figs. 2 a – 2 c; Tables 2 & 3; Morphbank 82; GenBank 83; Barcode 84)

Five new species of the damselfish genus Chromis (Perciformes: Labroidei: Pomacentridae) from deep coral reefs in the tropical western Pacific

description

Description. Dorsal rays XIII, 14 (two paratypes with 13); anal rays II, 16 (one paratype with 15, another paratype deformed with only 13); all dorsal and anal rays branched, the last to base; pectoral rays 18 (one paratype with 19 on only the right side), the upper 2 and lowermost unbranched; pelvic rays I, 5; principal caudal rays 8 + 7 = 15 (one paratype with 7 + 7 = 14); upper and lower procurrent caudal rays 5, the anterior 3 (2 – 3) spiniform (when 3, the anteriormost vestigial and not penetrating scales), the posterior 2 segmented and unbranched; tubed lateral-line scales 15 (14 – 16); posterior midlateral scales with a pore or deep pit 7 (0 – 8); scales above dorsal fin to origin of dorsal fin 4 (3.5 – 4); scales below lateral line to origin of anal fin 10 (9 – 10, usually 10); gill rakers 8 + 21 = 29 (6 – 8 + 19 – 22 = 26 – 29, 6 gill rakers on upper limb of gill arch in one paratype, 22 gill rakers on lower limb of gill arch in one paratype); surpaneural (predorsal) bones 3; vertebrae 12 + 13. Body moderately deep, depth 1.69 (1.57 – 1.77) in SL, and compressed, the width 3.04 (2.94 – 3.75) in body depth; head length 3.13 (2.71 – 3.26) in SL; dorsal profile of head smooth

Five new species of the damselfish genus Chromis (Perciformes: Labroidei: Pomacentridae) from deep coral reefs in the tropical western Pacific

diagnosis

Diagnosis. Dorsal rays XIII, 13 – 14 (usually 14); anal rays II, 15 – 16; pectoral rays 18 – 19 (usually 19); spiniform caudal rays 2 – 3 (usually 3); tubed lateral-line scales 14 – 16; gill rakers 6 – 8 + 19 – 22 (usually 6 – 7 + 19 – 21; total 26 – 29); body depth 1.57 – 1.77 in SL; color when fresh pale lavender-tinged gray dorsally, paler ventrally; three or four rows of scales dorsally from nape to upper caudal peduncle with gold edges; small scales on basal sheath of dorsal fin almost entirely gold; median fin membranes lavender gray or translucent blue, suffused with gold color; iris yellow.

Five new species of the damselfish genus Chromis (Perciformes: Labroidei: Pomacentridae) from deep coral reefs in the tropical western Pacific

discussion

Remarks. Generally abundant in its typical environment, which is characterized by steep slopes and drop-offs at depths of about 90 – 120 m. Usually found in association with small holes and limestone talus, often in aggregations ranging from a half-dozen to several dozen individuals feeding low in the water column.

Five new species of the damselfish genus Chromis (Perciformes: Labroidei: Pomacentridae) from deep coral reefs in the tropical western Pacific