Amblyeleotris bleekeri, Chen & Shao & Chen, 2006

Chen, I-Shiung, Shao, Kwang-Tsao & Chen, Jeng-Ping, 2006, Two new species of shrimp gobiid, Amblyeleotris (Teleostei: Gobiidae), from the West Pacific, Journal of Natural History 40 (44 - 46), pp. 2555-2567 : 2556-2560

Amblyeleotris bleekeri new species

( Figures 1A and 2 )

Materials examined

Holotype. ASIZP 0064286, 57.7 mm SL, 12 m depth, Sogang , Penghu County, Taiwan, 23 April 1991, coll. JP Chen.

Paratypes. NMMB P 7903, 2 specimens, 12.0–14.2 mm SL, 19 m depth, Guihou, Taipei County, Taiwan, coll. JP Chen.

Diagnosis

Amblyeleotris bleekeri is distinguished from all congeners by the unique combination of the following features: (1) meristic features: D1VI; D2 I/13; A I/14; P 19, LR 62–63; TR 21; no predorsal scale; (2) pelvic fin: very low connecting membrane and lacking frenum; and (3) coloration: head and body of pale white background with five vertical brown bands; interspaces of bands with 111-shaped brown marks; a longitudinal blackish brown stripe behind orbit; a deep brown spot behind upper lip; first dorsal fin with several oblique rows of light yellow stripes and caudal fin translucent with a C-shape brown mark.

Description. Body proportions in Table I. Head and body moderately compressed. Eyes large. Mouth large and oblique, maxillary extending to a vertical of posterior margin of orbit. Lower jaws with three to four rows of subconical teeth; outer rows elongated and separated. Inner teeth inwardly curved, two to three large canines on each side. Snout is rather blunt, shorter than orbit. Bony interorbital is very narrow. Gill opening extending forward below posterior margin of orbit. Anterior nostril a short tube. Posterior nostril a round hole. Opercle and preopercle edges smooth. Isthmus narrow. 10+16526 vertebrae.

Fins. D1VI; D2 I/13; A I/14; P 19; V I/5. D1 II, III longest, extending to first branched ray of D2 when depressed. D2 base and A base long, rear tips reaching beyond the upper procurrent rays of C. A origin inserted below second branched rays of D2. P large, extending just reaching the edge of anus. C lanceolate. V rather long, extending beyond the origin of A and fourth branched rays longest; the connecting membrane very low, less than 1/10. No pelvic frenum.

Scales. Body with very small cycloid scales anteriorly and ctenoid scales posteriorly. Longitudinal scale rows 62–63; transverse scale rows 21; predorsal scale 0. Ventral body covered with rather small cycloid scales. Midline of nape naked. Scales on sides extend forward approximately to the midline edge of the opercle. Scales absent on opercle, cheek and pectoral fin base.

Head lateral-line system ( Figure 1A ). Canals: anterior oculoscapular canal with paired terminal pore S, single pore l and single pore K on interorbital region, paired v behind orbit; and paired lateral side of canals with pores a, B, and terminal pores R. Posterior oculoscapular canal with two terminal pores H and T. Preopercular canal with pores c, d and E.

Sensory papillae. Six main transverse rows of papillae, row 1, 2, 3, 4 vertical. Row 5 and 6 separated as row 5s, 5i and 6s, 6i respectively. Row b short. Row d rather long. Row f paired. Other papillae shown in detail in Figure 1 .

Colouration in life ( Figure 2 ). Head and body of pale white background with five brown bands, which are deeper in middle region. The first band on the opercle; the second one below first dorsal fin base; the third band and fourth one under second dorsal fin base; fifth band on caudal peduncle. Dorsal side with a series of eight brown spots from nape to caudal fin base, each composed of two separated, symmetrical spots along both sides of two dorsal fin bases. The interspaces between lateral brown bands consist of three vertical brown lines forming a 111-shape; the middle row shorter and somewhat zigzagged, and shorter than anterior and posterior rows. A row of round brown spots from upper gill opening to caudal fin; the first shoulder spot seems to be more conspicuous than the remaining brown spots on the 111-shaped line just above longitudinal midline on body. Dorsal half of body light pale brown. Two greyish-brown marks on inter-orbital side of eyeballs. Cheek with several light blue spots, a conspicuous, thin longitudinal blackishbrown stripe behind orbit extending along lateral region of oculoscapular canal to upper gill opening. Opercle with a deep brown mark in upper half. A round deep brown spot just behind upper lip. Snout with a pair of brown spots. First dorsal fin with several oblique rows of light yellow stripes with alternative pale stripes. Second dorsal base with a very light greyish-purple band with about 35 round yellow spots arranged as two to three rows. Pectoral fin pale white and pectoral fin base with a vertical orange stripe and a conspicuous deep brown spot on upper region. Anal fin white and distal region purple grey with two to three light yellow spots. Caudal fin translucent with a C-shaped brown mark. Pelvic fin light greyish-yellow.

Distribution

This new species has only been found in the coastal regions off northeastern Taiwan and the Penghu islands.

Etymology

The new species is named after the famous Dutch ichthyologist, Dr. P. Bleeker who has made significant contributions to Indo-Pacific fish research and also created this marine gobiid genus Ambyeleotris.

Remarks

The new species is more similar to the Japanese species Amblyeleotris masuii Aunoma and Yoshino, 1996 than to any other congener by overall colouration pattern. However, Amblyeleotris bleekeri is well distinguished from Amblyeleotris masuii by the following combination of features: (1) longitudinal scale rows: 62–63 versus 92–97; (2) shape of first dorsal fin: II, III longest versus all about equal; (3) anal fin rays: 14 versus 13; (4) pelvic fin: frenum absent and very low CM (,1/10) versus frenum present and CM 0.4–0.7; and (5) head colouration: a longitudinal blackish-brown stripe behind orbit and a round deep brown spot just behind upper lip versus no such marks.

This new species is also somewhat similar to the central Pacific species Amblyeleotris rubrimarginata Mohlmann and Randall, 2002 by the value of fin rays counts and low CM value. However, Amblyeleotris bleekeri is well distinguished from Amblyeleotris rubrimarginata by the following combination of features: (1) longitudinal scale rows: 62–63 versus 77–94; (2) pelvic fin: frenum absent versus frenum present; (3) fin colouration: D2 with thin distal brown margin and no shiny spots on D2 and C versus a conspicuous red margin or rows of small red spots on D2 and C. Amblyeleotris bleekeri also shares similarities in some colouration patterns as well as dorsal and anal fin rays counts with Amblyeleotris triguttata Randall, 1994 . Amblyeleotris bleekeri is easily distinguished from Amblyeleotris triguttata as follows: (1) pectoral fin rays: 19 versus modally 20; (2) longitudinal scale rows: 62–63 versus 96–104; and (3) colouration: first dorsal fin in lacking large mark versus first dorsal fin in having a red-edged black blotch at base.

Figures

Figure 1. Head lateral-line system of (A) Amblyeleotris bleekeri, holotype and (B) Amblyeleotris taipinensis, holotype.

Figure 2. Amblyeleotris bleekeri n. sp., (A) 57.7 mm SL, holotype, ASIZP 064286; (B) underwater photo of a live specimen, CA. 60 mm SL, northeastern Taiwan.