Spring Chromis

description

(Figs. 5 a – 5 c; Tables 3 & 6; Morphbank 137; GenBank 138; Barcode 139)

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, 12 (one paratype with XII, another with 11); anal rays II, 12; all dorsal and anal rays branched, the last to base in some specimens; pectoral rays 18 (17 – 18), the upper 2 and lowermost unbranched; pelvic rays I, 5; principal caudal rays 8 + 7 = 15; upper and lower procurrent caudal rays 5, the anterior 3 spiniform, the posterior 2 segmented and unbranched; tubed lateral-line scales 15 (13 – 16, one paratype with 16); posterior midlateral scales with a pore or deep pit 8 (4 – 8); scales above lateral line to origin of dorsal fin 3; scales below lateral line to origin of anal fin 9 (8 – 9); gill rakers 7 + 21 = 28 (6 – 8 + 18 – 21 = 26 – 28, one paratype with 25); surpaneural (predorsal) bones 3; vertebrae 12 + 13. Body moderately deep, depth 1.90 (1.65 – 1.89) in SL, and compressed, the width 3.29 (2.71 – 3.70) in body depth; head length 2.96 (2.82 – 3.14) in SL; dorsal profile of head with convexity anterior to eye and concavity dorsal to eye; snout shorter than orbit diameter, its length 3.57 (3.52 – 4.40) in head length; orbit diameter 2.27 (2.11 – 2.40) in head length; interorbital space convex, its width 2.73 (2.60 – 3.22) in head length; cauda

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

diagnosis

Diagnosis. Dorsal rays XII – XIII, 11 – 12 (usually XIII, 12); anal rays II, 12; pectoral rays 17 – 18 (usually 18); spiniform caudal rays 3; tubed lateral-line scales 13 – 15 (rarely 16); gill rakers 6 – 8 + 18 – 21 (total 26 – 28, rarely 25); body depth 1.65 – 1.9 in SL; color when fresh pale slate blue (bright pale green in life); a white spot (sometimes two white spots) roughly the size of a scale mid-laterally on the body; malachite green area above orbit and in inter-orbital space and nape; dorsal and anal fins with bright distal border of pale turquoise blue.

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

discussion

Remarks. This species inhabits the same general habitat as the other new species described herein: steep outer reef slopes and drop-offs with rocky outcrops and small caves and holes, often in association with limestone talus. It is often observed in pairs or small groups, feeding low in the water column, and is generally abundant where it is found. Similarities with other species are discussed in the Remarks section under the account of C. brevirostris.

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