Wednesday, 13 August 2008

Cirrhilabrus beauperryi, a new wrasse


Gerald R. Allen, Joshua Drew and Paul Barber: Cirrhilabrus beauperryi, a new wrasse (Pisces: Labridae) from Melanesia, pp. 129-140

Abstract

Cirrhilabrus beauperryi

Underwater photograph of terminal phase (male) Cirrhilabrus beauperryi in courtship display, approximately 115 mm TL, 15 m depth, Milne Bay Province, Papua New Guinea. Photo by G. R. Allen.

Cirrhilabrus beauperryi is described from eight specimens, 49.0-85.1 mm SL, collected at Milne Bay Province, Papua New Guinea. Field observations also reveal its occurrence at the Bismarck Archipelago (New Britain, New Ireland, and Manus), Madang (Papua New Guinea), and Solomon Islands. The new species is closely related to and has frequently been confused with C. punctatus from Fiji, Tonga, New Caledonia, eastern Australia and southern Papua New Guinea. The two species are clearly separable on the basis of colour pattern.

Terminal-phase individuals of C. beauperryi are generally purplish grading to blue ventrally and greenish or yellowish brown dorsally with a broad purple stripe along the basal half of the otherwise pale yellow dorsal fin. In contrast, terminal-phase C. punctatus are generally reddish brown to dark grey on the upper two-thirds of the head and body and abruptly white below with broad black stripes along the base of mainly red dorsal and anal fins. They also differ noticeably with respect to the colouration on the base of the pectoral fins: in C. beauperryi it is mainly violet with a narrow, inconspicuous purple bar; that of C. punctatus is prominently marked with a broad black bar.

The pectoral-base marking is also useful for distinguishing initial-phase fish. The terminal phase of C. beauperryi also exhibits a unique median head profile characterised by a rounded forehead and concave interorbital region.

DNA analysis reveals the two species are genetically distinct. (PDF)

Aqua, International Journal of Ichthyology

Scuba Diving Fiji

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