Volume 14, Issue 3, 10 July 2008
Volume 14, Issue 3 – 10 July 2008
Gerald R. Allen, Joshua Drew and Les Kaufman: Amphiprion barberi, a new species of anemonefish (Pomacentridae) from Fiji, Tonga, and Samoa, pp. 105-114
Amphiprion barberi, a new species of anemonefish fish, is described from 46 specimens, 16.3-85.8 mm SL, collected at depths of 2-10 m from coral reefs of Fiji, Tonga, and Samoa. It is closely allied to A. melanopus, which is widely distributed in the western Pacific. The two species exhibit significant colour-pattern differences, including a mainly reddish orange body in A. barberi and dark brown or blackish body in A. melanopus. Adults of the new species also possess fewer spinules (11-19 versus 19-26) in the upper-opercular series than A. melanopus. Genetic data presented here confirms the separation of these species.
Amphiprion melanopus, underwater photograph of adult, about 75.0 mm SL, Milne Bay, Papua New Guinea, 3 m depth. Photo by G. R. Allen
Edward O. Murdy: Paratrypauchen, a new genus for Trypauchen microcephalus Bleeker, 1860, (Perciformes: Gobiidae: Amblyopinae) with a redescription of Ctenotrypauchen chinensis Steindachner, 1867, and a key to ‘Trypauchen’ group genera, pp. 115-128
A new genus, Paratrypauchen, is described for Trypauchen microcephalus. Paratrypauchen microcephalus differs from Trypauchen in having: a scaleless abdomen, pelvic fins with an emarginate interradial membrane, and three pterygiophores anterior to the first hemal spine. Due to these differences, P. microcephalus has been assigned to Ctenotrypauchen by many recent authors. However, P. microcephalus differs notably from Ctenotrypauchen in the absence of a prominent serrated frontal crest and in lacking scales on the abdomen. The new genus is compared to Ctenotrypauchen, Trypauchen and other ‘Trypauchen’ group members.
Left side of head of partially dissected specimen of Paratrypauchen microcephalus (100.8 mm SL) from USNM 285219
Gerald R. Allen, Joshua Drew and Paul Barber: Cirrhilabrus beauperryi, a new wrasse (Pisces: Labridae) from Melanesia, pp. 129-140
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.
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.
Kapil Mandrekar and Ronald G. Oldfield: Prior residency and social experience in contests between similar-sized juvenile black Midas cichlids, Amphilophus astorquii, pp. 141-148
The possible roles of chemical cues and a 3-D structure in eliciting a prior residency effect in juvenile black Midas cichlids, Amphilophus astorquii, were tested under laboratory conditions. The effect of recent social interaction on the outcome of contests was also tested. Fish with a clay pot in their pre-test tanks defeated opponents without such prior experience when test tanks contained an identical pot. Experience in a small group of conspecifics had no significant effect on contest outcome, although fish that held lower size ranks tended to lose contests. The subjects’ chemical cues did not result in a prior residency effect. Interestingly, juvenile Amphilophus cichlids are not typically aggressive in their natural environment. The current results demonstrate that, despite this, they are sufficiently plastic to behave aggressively when resources are made to be defensible by artificially reducing attack distance and number of competitors. In addition, the ability to modify aggressive behavior according to prior experience demonstrates a further degree of plasticity. This suggests that complex behavioral plasticity relating to aggression may generally be of such high adaptive value that it might occur in species for which it might seem to typically have little utility.
Juvenile Amphilophus astorquii. Photo by R. G. Oldfield
John E. Randall1, John L. Earle and Luiz A. Rocha: Xyrichtys pastellus, a new razorfish from the southwest Pacific, with discussion of the related X. sciistius and X. woodi, pp. 149-158
Five species of razorfishes of the genus Xyrichtys are known from the central and western Pacific: X. woodi from the Hawaiian Islands; X. sciistius (formerly a synonym of X. woodi) from Japan and Taiwan; X. pastellus, described as new from two specimens from Lord Howe Island and three from Elizabeth and Middleton Reefs, New South Wales; X. halsteadi from Papua New Guinea to Tahiti; and X. koteamea from Easter Island. The first three form a complex of closely related species that are distinguished mainly by color, but also by DNA. In addition, X. woodi has a lower modal gill-raker count than the other two sister species.
Holotype of Xyrichtys pastellus, presumed female, AMS I.43850-001, 106 mm SL, Lord Howe Island. Aquarium photo by G. Kelly
Matthew T. Craig, John E. Randall and Mark Stein: The Fourspot Butterflyfish (Chaetodon quadrimaculatus) from the Philippines and the Solomon Islands, first records for the East Indies and Melanesia, pp. 159-164
Chaetodon quadrimaculatus is cited in the literature from the islands of Polynesia and Micronesia to southern Japan and Taiwan, but not the islands of Melanesia or the East Indies. It is reported here as a first record for Melanesia from a single specimen collected in New Georgia, Solomon Islands, and a first record for the East Indies by two specimens from Samar in the Philippines obtained in the aquarium fish trade. A genetic comparison of Philippine and Hawaiian material revealed no differences indicating conspecific populations. We also report the species from Minami Tori Shima (formerly Marcus Island) in the North Pacific.
Chaetodon quadrimaculatus, Kona, Hawaiian Islands. Underwater photo by J. E. Randall