aqua International Journal 13(3-4)
Volume 13, Issue 3-4 – 25 January 2008
Volume 13, Issue 3-4 – 25 January 2008
Gerald R. Allen and Mark V. Erdmann: Two new species of bamboo sharks (Orectolobiformes: Hemiscylliidae) from Western New Guinea, pp. 93-108
Two new species of hemiscylliid sharks are described from the Bird’s Head region of western New Guinea (Papua Barat Province, Indonesia). They differ from congeners on the basis of both colour patterns and DNA composition. Hemiscyllium galei is described from two specimens, 542.5-567.5 mm TL, collected at Cenderawasih Bay. The species is similar in appearance to H. freycineti, reported from areas immediately westward including the Raja Ampat Islands. The new species differs from H. freycineti in possessing white lines and spots along the margin of the large, dark dorsal saddles as well as scattered white spots, mainly on the upper side. In addition, H. galei is characterised by a row of about seven well-defined, horizontally-ovate, dark spots on the lower side between the abdomen and caudal-fin base. Hemiscyllium henryi is described from three specimens, 564.0-815.0 mm TL, collected in the vicinity of Triton Bay. It is most similar in general appearance to H. ocellatum from northern Australia, but differs in the structure of the post-cephalic ocellus (usually a pair of merged “twin-ocelli” with a poorly defined white halo) and possesses well-defined dark brown saddles/bars along the back and dorsal margin of the caudal fin as well as a dark spot at the origin of the pectoral and pelvic fins. A final difference concerns the presence of numerous small brown spots on the dorsal fins of H. ocellatum, in contrast to the mainly spotless pattern on the dorsal fins of H. henryi.
Gerald R. Allen and Peter J. Unmack: A new species of rainbowfish (Melanotaeniidae: Melanotaenia), from Batanta Island, western New Guinea, pp. 109-120
A new species of rainbowfish, Melanotaenia synergos, is described on the basis of 45 specimens, 24.1-63.3 mm SL, collected in 1998 at Batanta Island, western New Guinea (Papua Barat Province, Indonesia). It is closely allied to M. catherinae from the nearby island of Waigeo in the Raja Ampat Group. The two species share similar meristic and morphological features as well as general colour pattern similarities. However, they differ in modal counts for pectoral-fin rays and lateral scales. They also exhibit slight colour pattern differences related to the width of the dark midlateral stripe, which is generally narrower in M. synergos, covering one and a half scale rows for most of its length versus 2 to 3 scale rows for M. catherinae. Analysis of genetic relationships based on cytochrome b sequences indicates a close relationship between the two species. Of four species that were analysed (M. synergos, M. catherinae, M. batanta, and M. affinis) the mean Kimura 2-parameter genetic divergences between species varied from 1.3 to 17.1%. The new species differed from M. catherinae by between 2.4 and 2.7%.
Gerald R. Allen and Mark V. Erdmann: Corythoichthys benedetto, a new pipefish (Pisces: Syngnathidae) from Indonesia and Papua New Guinea, pp. 121-126
A new species of pipefish, Corythoichthys benedetto, is described on the basis of five specimens, 59.5-67.6 mm SL, collected in 5 to 15 m depth from rock and coral reefs at two Indonesian locations including Triton Bay, Papua Barat Province (western New Guinea) and Kabaena Island, off southern Sulawesi. Underwater photographs also indicate its occurrence at Bali and Flores, Indonesia and Madang, Papua New Guinea. It is most similar to C. amplexus, which is widely distributed in the Indo-western Pacific region. The two species differ notably in colour pattern: C. benedetto is overall pale with about 12 relatively narrow dark (red in life) bars, whereas C. amplexus is overall dark brown with 10-13 narrow white bars. In addition C. benedetto has a red caudal fin with a white posterior margin compared to the mainly white caudal fin of C. amplexus. The two species also exhibit a strong modal difference in the number of dorsal-fin rays (24-25 for C. benedetto versus a usual range of 26-28 for C. amplexus).
Gerald R. Allen and Mark V. Erdmann: Pterois andover, a new species of scorpionfish (Pisces: Scorpaenidae) from Indonesia and Papua New Guinea, pp. 127-138
A new species of scorpionfish, Pterois andover, is described on the basis of six specimens, 83.9-168.0 mm SL, collected at southwestern Halmahera and western New Guinea (Papua and Papua Barat provinces, Indonesia). It has also been photographed at northern Sulawesi and Flores, Indonesia and Milne Bay Province, Papua New Guinea. The new taxon superficially resembles P. volitans, a sympatric widespread Pacific species, but differs in having larger body scales ( 81 and 18-25 respectively) and usually 13 versus 14 pectoral-fin rays. The two species are readily distinguished underwater on the basis of dorsal fin morphology, particularly the shape and colour of the spine membranes. Pterois andover possesses a narrow membrane posteriorly on each spine, which is more or less uniform brown and terminates in an exaggerated pennant-like structure. In contrast, the membranes of P. volitans are broader, boldly striped, and usually lack a well differentiated terminal pennant. The new species also has consistently fewer and fainter spots on the caudal, soft-dorsal, and soft-anal fins except for the population of P. volitans from western Australia.
Gerald R. Allen and Mark V. Erdmann: Pseudanthias charleneae, a new basslet (Serranidae: Anthiinae) from Indonesia, pp. 139-144
Pseudanthias charleneae is described from a single specimen, 75.3 mm SL, collected at Cenderawasih Bay, western New Guinea (Papua Province, Indonesia) at a depth of 56 m. It is also reported from Bali, Indonesia on the basis of colour photographs. Diagnostic features include: X,16 dorsal rays; II,7 anal rays; 17-18 pectoral rays; 47 lateral-line scales; 28 circumpedunclar scales; 11 + 26 gill rakers on the first branchial arch; an elevated third dorsal spine; and male colour in life (mainly lavender pink, grading to orange on head and anterodorsal part of body with a broad, tapering orange bar below middle of spinous dorsal fin and a lavender-pink margined yellow band from the snout tip to the pectoral-fin base). It is most similar to P. carlsoni from Melanesia (Papua New Guinea to Fiji) and P. engelhardi from the Great Barrier Reef of Australia, but differs in having a complete rather than incomplete bar below the middle of the spinous dorsal fin and in lacking a large red spot on the spinous dorsal fin. It also differs in having a higher lateral-line scale count (47 versus 41-45), more circumpeduncular scales (28 versus 25), and a deeper caudal peduncle (least depth 1.8 in HL versus 2.15-2.3).
Gerald R. Allen, Anthony C. Gill and Mark V. Erdmann: A new species of Pictichromis (Pisces: Pseudochromidae) from western New Guinea with a redescription of P. aurifrons, pp. 145-154
The coral reef fish previously known as Pictichromis aurifrons is shown to consist of two species including P. caitlinae, which is described as new based on eight specimens, 26.3-42.6 mm SL, from Cenderawasih Bay, western New Guinea. Although both species are known only from New Guinea, the two are geographically separated by approximately 2,700 km of coastline. They share a characteristic yellow snout and forehead, but differ in several other colour pattern features. The most obvious difference is the general hue of the body, which is bright magenta in P. caitlinae and light purple to bluish grey in P. aurifrons. The gradation between the two basic colours is relatively gradual in P. aurifrons in contrast to the abrupt transition in P. caitlinae. A redescription of P. aurifrons, originally described on the basis of a single specimen, is included as well as a key to the species of Pictichromis.
Gerald R. Allen, Anthony C. Gill and Mark V. Erdmann: A new species of Pseudochromis (Pisces: Pseudochromidae) from Papua Barat Province, Indonesia, pp. 155-162
Pseudochromis jace is described from three specimens, 37.9-62.5 mm SL, collected in the vicinity of Triton Bay, Papua Barat Province (western New Guinea), Indonesia. It is most similar to P. pictus from the Indonesian island of Alor, which lies about 1130 km southwest of Triton Bay, and to P. reticulatus from off north-western Australia. The three species are easily separated on the basis of colour pattern, particularly dorsal coloration, and degree of development of a dark stripe on the upper body. The new species is also similar in coloration to P. perspicillatus from the Indo-Malayan region, although the latter fish has prominent dark spots on the nape area and has a different palatine tooth patch structure.
Gerald R. Allen and Mark V. Erdmann: Pterocaesio monikae, a new species of fusilier (Caesionidae) from western New Guinea (Papua and Papua Barat provinces, Indonesia), pp. 163-170
A new species of caesionid fish, Pterocaesio monikae, is described on the basis of 21 specimens, 51.8-97.5 mm SL, collected at Cenderawasih Bay, Papua and Papua Barat provinces, Indonesia during February 2006 and October 2007. It was observed in large schools containing up to several hundred individuals along the upper edge of seaward reef slopes at depths ranging from the surface to 55 m. It is closely related to P. lativittata, which is widely distributed in the Indo-west and central Pacific region. The two species share an unusually slender body shape and colour pattern consisting of a single, relatively broad yellow stripe on the upper side. However, the centre line of the stripe on P. lativittata is positioned below the lateral line, whereas in P. monikae it is above the lateral line. Moreover, the stripe extends farther forward in P. lativittata, usually tapering to a point above the centre of the eye. In P. monikae, the stripe terminates well behind the eye, generally above the posterior margin of the operculum. The two species are also readily distinguished on the basis of transverse scale row counts above and below the lateral line: P. monikae usually has 7 (rarely 6) rows above and 13 (occasionally 12, rarely 14) rows below compared to 9-11 rows above and 15-19 below for P. lativittata. Moreover, there are modal differences in the number of lateral-line scales, circumpeduncular scales, and pectoral-fin rays, with P. monikae exhibiting a trend of lower counts. Finally, P. monikae is a much smaller fish, attaining a maximum size of about 130 mm total length compared to an approximate total length of 200-250 mm for P. lativittata.
Gerald R. Allen and Mark V. Erdmann: A new species of damselfish (Pomacentridae: Chrysiptera) from western New Guinea and the Togean Islands, Indonesia, pp. 171-178
Chrysiptera giti is described from nine specimens, 23.4-36.0 mm SL, from the Fak Fak Peninsula of western New Guinea (Papua Barat Province, Indonesia). Underwater photographs also reveal its presence at the Togean Islands off northeastern Sulawesi. A separate genetic study currently in progress indicates it belongs to a monophyletic clade of four species that includes C. hemicyanea (southern Sulawesi, Kei Islands, and western New Guinea), C. parasema (western Indonesia, Sabah, and the Philippines), and an undescribed species (Chrysiptera species B from northern New Guinea and north Sulawesi). The members of this group are characterised by a brilliant blue coloration with variable amounts of yellow on the posterior/ventral portion of the body. It most closely resembles C. hemicyanea. Both species have the posterior portion of the body abruptly yellow behind an oblique line extending forward from the upper caudal-fin base. The yellow coloration extends forward to the anal fin origin in C. giti, but in C. hemicyanea it also embraces the breast and lower one-fourth of the body. A key to the 10 members of the “hemicyanea complex” of Chrysiptera species is provided as well as comparative underwater photographs of the three species most closely related to C. giti.
Gerald R. Allen and Mark V. Erdmann: Paracheilinus nursalim, a new species of flasher wrasse (Perciformes: Labridae) from the Bird’s Head Peninsula of western New Guinea with a key to the species of Paracheilinus, pp. 179-188
Paracheilinus nursalim is described from 16 male specimens, 39.4-51.0 mm SL, and three females, 20.9-28.9 mm SL, collected at the Fak Fak Peninsula and Triton Bay area of western New Guinea. It is distinguished from all other members of the genus on the basis of coloration of adult males, particularly the presence of a pair of prominent blackish patches, one below the anterior dorsal fin and another covering the ventral half of the caudal peduncle. Males also possess unusually long caudal fin filaments, which extend for about 50% of the standard length in some individuals. The new species most closely resembles the sympatric P. cyaneus (northeast Kalimantan, Sulawesi, and western New Guinea), but is easily distinguished on the basis of the previously mentioned features as well as its predominately orange ground colour compared to the magenta or reddish coloration of P. cyaneus. The latter species further differs in having a dark triangular marking on the spinous dorsal fin, red dorsal and ventral margins on the caudal fin, which extend onto the filamentous lobes, and a blue band below the eye that is about twice the width of a similarly-positioned band in P. nursalim. A key is provided for distinguishing the 16 species of the genus.
|Dimensions||26.6 × 20.3 × 0.5 cm|
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