Chromis kennensis Whitley, 1964

Iwatsubo, Hiroki & Motomura, Hiroyuki, 2013, Redescriptions of Chromis notata (Temminck and Schlegel, 1843) and C. kennensis Whitley, 1964 with the Description of a New Species of Chromis (Perciformes: Pomacentridae), Species Diversity 18, pp. 193-213 : 204-209

Chromis kennensis Whitley, 1964

[Australian English name: Yellow-spotted Chromis ] ( Figs 8 , 9 , 11 , 12E ; Tables 3–4)

Chromis kennensis Whitley, 1964: 182 , Fig. 12 (type locality: Kenn Reef, Coral Sea); Allen 1975: 81, 83, unnumbered fig. (Kenn Reef, Coral Sea; Lord Howe Island; Sydney, Australia; Ouvea Island , Loyalty Islands, New Caledonia) .

Chromis flavomaculata (not of Kamohara): Allen 1991: 68 (Ouvea Island, Loyalty Islands, New Caledonia; Lord Howe Island; Coral Sea; eastern Australia between southern Great Barrier Reef and Sydney); Kuiter 1993: 237, unnumbered fig. (Coral Sea to Montague Island; Lord Howe Island); Randall et al. 1997: 258, unnumbered fig. (Coral Sea; Lord Howe Island; New Caledonia); Randall 2005: 357, unnumbered fig. (southern Great Barrier Reef to New South Wales; Lord Howe Island; Norfolk Island; New Caledonia); Allen et al. 2006: 1449, (Lord Howe Island; Great Barrier Reef, Queensland to Montague Island, New South Wales, Australia); Kuiter and Debelius 2006: 530, unnumbered fig. ( Australia); Kato 2011b: 58 (Great Barrier Reef; New Caledonia; Tonga); Allen et al. 2012: 80 (eastern Australia and Coral Sea); Allen and Erdmann 2012: 580 (eastern Australia; Coral Sea; New Caledonia; northern tip of New Zealand).

Holotype. AMS IB. 4973, 77.6 mm SL, Kenn Reef,

Coral Sea, D. McMichael.

Non-type material examined. 23 specimens, 22.5– 93.0 mm SL— AUSTRALIA: AMS I . 17357-023, 43.0 mm SL, off Phillip Point, Lord Howe Island , New South Wales, 31°05′S, 159°01′E, G . Allen et al .; AMS I. 17376-008, 4 specimens, 33.6–35.1 mm SL, Lord Howe Island , New South Wales, 31°50′S, 159°10′E, F . Talbot et al .; AMS I. 17380-006, 2 specimens, 22.5–23.8 mm SL, Lord Howe Island , New South Wales, 31°50′S, 159°10′E, AMS party; AMS I . 17737- 001, 48.8 mm SL, Long Bay, Sydney , New South Wales, 33°07′S, 151°03′E, R . Kuiter ; AMS I . 27139–024, 71.4 mm SL, Middleton Reef, Coral Sea , 29°48′67″S, 159°06′83″E, A . Gill et al .; AMS I. 27891-043, 2 specimens, 59.0– 62.2 mm SL, Elizabeth Reef, Coral Sea, 29°09′S, 159°00′E, D . Williams et al .; BPBM 14766 , 3 specimens, 30.0–33.0 mm SL, Lord Howe Island , New South Wales, 20–27 m depth, 6 February 1973, spear, J . Randall and G . Allen; BPBM 33664 , 3 specimens, 79.0–82.0 mm SL, Coral Sea , 19°52′S, 158°19′E, 9 m depth, 24 August 1988, J . Randall et al . NEW CALEDONIA: BPBM 11438 , 70.4 mm SL, 1 km northwest of Dumbae Pass , Nouméa, 15–18 m depth, J . Randall et al .; USNM 319941 , 31.8 mm SL, Ouvea Island , Loyalty Islands, 20°39′30″S, 166°23′00″E, 18 m depth, 14 November 1991, J . Williams et al .; USNM 319942 , 82.1 mm SL, Bagaat Islet, Ouvea Atoll , Loyalty Islands, 20°37′18″S, 166°16′08″E, 15–22 m depth, 16 November 1991, J . Williams , et al .; USNM 319943 , 74.8 mm SL, Ouvea Island , Loyalty Islands, 20°34′12″S, 166°14′12″E, 5 m depth, 16 November 1991, J . Williams et al . TONGA: USNM 332432 , 28.9 mm SL, Ha’atafu Beach , Tongatapu, 21°03′58″S, 175°20′03″W, 5.5– 7.9 m depth, 21 October 1993, J . Williams , et al .

Diagnosis. A species of Chromis with the following combination of characters: dorsal fin rays XIII, 11–13 (mode XIII, 12); anal fin rays II, 10–12 (11); pectoral fin rays 17–21 (19); principal caudal fin rays 15; spiniform caudal fin rays 2; scale rows in longitudinal series 24–27 (26); tubed lateral line scales 15–19 (18); scale rows above lateral line 3, scale rows below lateral line 9–10 (9); gill rakers 7–9 (8)+21–25 (24)=29–34 (32); preopercular margin smooth; caudal fin deeply forked, without prolonged filaments; basal width of pelvic fin axillary scale 0.6–1.8% of SL; basal width of scale between pelvic fin bases 2.0–2.8% of SL; prominent black blotch covering entire pectoral fin base throughout life; no white spot at end of dorsal fin base; caudal peduncle without distinct markings; caudal fin yellowish with no dark band along each fin lobe.

Distribution. Chromis kennensis is known only from the southwestern Pacific Ocean: the Coral Sea (Ken Reef, Middleton Reef, and Elizabeth Reef), Lord Howe Island, eastern Australia (Sydney), New Caledonia (Ouvea Island), and Tonga (Tongatapu) ( Fig. 9 ).

Remarks. Kamohara (1960) described Chromis flavomaculata (as flavomaculatus ) as a new species on the basis of a single specimen (BSKU 8482; Fig. 2D ) from Kochi, Japan, while also listing an additional non-type specimen (BSKU 4944) of the species from Tokushima, Japan. Examination of the holotype and non-type specimen showed them to be identical with C. notata in having four scale rows above the lateral line and 12 scale rows below, a black blotch restricted to the upper two-thirds of the pectoral fin base, and black bands along the caudal fin lobes ( Fig. 2 ; Tables 4, 5). Therefore, C. flavomaculata is herein regarded as a junior synonym of C. notata . In the same paper, Kamohara (1960) gave a description of two specimens of C. notata . These two specimens (BSKU 4946 and 8513) were examined and reidentified by us as C. notata and C. yamakawai sp. nov., respectively. Data for Kamohara’s (1960) specimens are given in Table 5.

A species of Chromis , previously identified as C. flavomaculata , is herein regarded as comprising two geographically disjunct species: C. yamakawai sp. nov. from the northwestern Pacific Ocean and C. kennensis from the southwestern Pacific Ocean ( Fig. 9 ). These two species can be distinguished from C. notata by having three scale rows above the lateral line and nine or 10 scale rows below (vs 4 or 5 and 11 or 12 in C. notata ; Tables 1–5), a black blotch covering the entire pectoral fin base in adults (vs restricted to the upper two-thirds of the pectoral fin base), and a yellow caudal fin without black bands (vs a grayish caudal fin with black bands along the lobes) ( Figs 3 , 8 , 10 ).

Chromis kennensis , previously regarded as a junior synonym of C. flavomaculata (e.g., Randall et al. 1997; Randall 2005; Allen et al. 2006), differs from C. yamakawai sp. nov. in coloration, meristics, and morphometrics. In young specimens, the dark blotch at the base of the pectoral fin is relatively large in C. kennensis , covering the entire fin base, whereas that of C. yamakawai is small, covering only the upper half of the fin base (the blotch becomes larger with growth in C. yamakawai ) ( Figs 8 , 10 ). In meristics, C. kennensis differs slightly from C. yamakawai in having fewer tubed lateral line scales (15–19 vs 16–21 in C. yamakawai ), and more gill rakers [21–25 (mode 24) lower gill rakers and 29–34 (32) total rakers vs 20–25 (23) and 27–33 (30), respectively] ( Table 3). In morphometrics, the basal width of the pelvic fin axillary scale is 0.6–1.8% of SL (mean 1.5%) in C. kennensis , whereas that of C. yamakawai is 1.4–2.8% (2.2%) ( Fig. 11 ; Table 4). The basal width of the scale between the pelvic fins in C. kennensis (2.0–2.8% of SL, mean 2.6%) also tends to be less than that of C. yamakawai (2.2–3.9%, 3.0%) ( Fig. 11 ; Table 4). Moreover, C. yamakawai grows larger than C. kennensis (largest recorded size 130.8 mm vs 93.0 mm SL).

Chromis kennensis and C. yamakawai are similar to C. pura Allen and Randall, 2004 , which is known only from the Alor Islands, Indonesia, in overall body appearance and general coloration, but C. pura has a yellowish caudal peduncle, darker yellow fins, and a smaller black blotch at the base of the pectoral fin ( Allen and Randall 2004: figs. 2, 3). Chromis pura also differs from the former two species in having fewer gill rakers (25–27 in C. pura vs 29–34 in C. kennensis and 27–33 in C. yamakawai ).

Figures

Fig. 8. Photographs of Chromis kennensis. A, AMS IB. 4973, holotype, 77.6mm SL; B, juvenile, New South Wales, Australia (photo by R. Kuiter); C, BPBM 14766, juvenile, 31.6mm SL, Lord Howe Island (photo by J. Randall); D, BPBM 11438, adult, 93.0mm SL, New Caledonia (photo by J. Randall).

Fig. 9. Distributional records of Chromis kennensis (◆) and C. yamakawai sp. nov. (★) on the basis of specimens examined in this study.Some symbols include more than one specimen.

Fig. 11. Relationships of (A) basal width of pelvic fin axillary scale and (B) basal width of scale between bases of pelvic fins to standard length in Chromis kennensis (◆) and C. yamakawai sp. nov. (★).

Fig. 12. Heads of three species of Chromis. A–D, C. notata (A, KAUM-I. 26534, 97.7mm SL, Tobi-shima island, Yamagata, Japan; B, KAUM-I. 33715, 104.5mm SL, Kagoshima, Japan; C, KPM-NI 24878, 100.0mm SL, Enoshima island, Kanagawa, Japan; D: ZUMT 53957, 126.3mm SL, Miyake-jima island, Izu Islands, Japan); E, C. kennensis (AMS IB. 4973, holotype, 77.6mm SL, Kenn Reef, Coral Sea); F,C. yamakawai sp. nov. (NSMT-P 111948, holotype, 83.0mm SL, Yoron-jima island, Kagoshima, Japan). AN, anterior nostril; PN, posterior nostril.

Fig. 2. Primary type specimens of nominal species regarded as Chromis notata. A, lectotype of Heliases notatus (RMNH.PISC. 895, 86.8mm SL); B, holotype of Chromis villadolidi (FMNH 59185, 101.0mm SL); C, holotype of Chromis miyakeensis (ZUMT 53957, 126.3mm SL); D, holotype of Chromis flavomaculatus (BSKU 8482, 84.8mm SL).

Fig. 3. Juveniles to adults of Chromis notata from different localities. A–C, specimens from the Sea of Japan (A, KAUM-I. 31033, 34.0mm SL; B, KAUM-I. 31045, 60.4mm SL; C, KAUM-I. 34910, 113.8mm SL). D–F, specimens from the Seto Inland Sea and East China Sea (D, KAUM-I. 10753, 33.7mm SL; E, KAUM-I. 7576, 59.0mm SL; F, KAUM-I. 33715, 104.5mm SL). G–I, specimens from the Pacific coast of Japan and southern China (G, KPM-NI 21975, 26.7mm SL; H, KAUM-I.25873, 68.2mm SL; I, KPM-NI 25259, 122.3mm SL).

Fig. 10. Photographs of Chromis yamakawai sp. nov. A, KAUM-I. 40100, juvenile, 31.9mm SL, Iou-jima island, Kagoshima, Japan; B, NSMT-P 111948, holotype, 83.0mm SL, Yoron-jima island, Kagoshima, Japan; C, juvenile, Hachijo-jima island, Izu Islands, Japan (photo by S. Kato); D, adult, Hachijo-jima island, Izu Islands, Japan (photo by S. Kato).