Jeffrey W. Johnson

Validity of the Poorly Known Scorpionfish, Rhinopias eschmeyeri, with Redescriptions of R. frondosa and R. aphanes (Scorpaeniformes: Scorpaenidae)

Abstract The validity of the scorpionfish, Rhinopias eschmeyeri, known only from the holotype from Mauritius, is confirmed, and the species is redescribed in detail on the basis of ten specimens from the Indo-West Pacific Ocean (Mascarene Islands to Japan and Australia). Additionally, R. frondosa and R. aphanes are redescribed. These three species are characterized by having one or two small dense black spots in the soft dorsal fin; the opercle without scales between the tips of the upper and lower opercular spines and the opercular margin; and 16 (rarely 15 or 17) pectoral-fin rays. Rhinopias eschmeyeri differs from the latter two species in aspects of form, location, and number of tentacles on the head and body; form of dorsal-fin margins and caudal-fin ray tips; shape of penultimate dorsal-fin spine; degree of development in lacrimal and suborbital ridge; and coloration.

A New Genus and Species of the Shallow-Water Anglerfish Family Tetrabrachiidae (Teleostei: Lophiiformes: Antennarioidei) from Australia and Indonesia

Abstract A new genus and species of anglerfish, Dibrachichthys melanurus, of the antennarioid family Tetrabrachiidae, is described on the basis of 42 specimens collected in near-shore coastal waters of Queensland, Northern Territory, Western Australia, and the Aru Islands, southeastern Indonesia. It differs most strikingly from its sister species, Tetrabrachium ocellatum, the only previously described tetrabrachiid, in having the pectoral fin entire, rather than having the rays divided into two distinct sections, a feature that was heretofore diagnostic for the family. The new taxon is diagnosed, described, and compared osteologically with its sister taxon using high-resolution, X-ray computed tomography.

Naso mcdadei, a new species of unicornfish (Perciformes : Acanthuridae), with a review of the Naso tuberosus species complex

An immaculate square-nosed acanthurid fish of the genus Naso, previously misidentified as N. tuberosus, is described as a new species, N. mcdadei. The species is widespread, but appears uncommon, being known from only 10 specimens and five underwater photographs. It is described from specimens from tropical eastern and western Australia, southern Indonesia, Mauritius, and Natal, South Africa. Its occurrence is confirmed from off western Sumatra, the Maldives, Chagos Archipelago and southern Taiwan by photographs. It differs from N. tuberosus (Lacepede, 1801) and N. tonganus (Valenciennes, 1835) most notably through smaller, more numerous teeth and a generally uniform greyish colouration. The head, body and fins all lack numerous small dark spots that are variously present in the latter two species. In adults, it also differs through a squarish rather than rounded tuberosity on the snout, a shorter straighter nasal groove, lack of a discernible hump in the dorsal profile, smaller-scale tubercles, non-prominent jaws, and first rather than last dorsal spine longest. The species previously recognised as N. tuberosus is split into two closely related taxa, N. tonganus (Valenciennes) from the western Pacific and Indian Oceans and N. tuberosus Lacepede from the central and western Indian Ocean. These species differ mainly in the size and shape of the nasal tuberosity, dorsal profile, body depth, and colouration.

Plectorhinchus caeruleonothus, a new species of sweetlips (Perciformes: Haemulidae) from northern Australia and the resurrection of P. unicolor (Macleay, 1883), species previously confused with P. schotaf (Forsskål, 1775)

Two distinct haemulid fishes from Australia and the Indo-Australian Archipelago respectively have long been confused with Plectorhinchus schotaf (Forsskål, 1775). Plectorhinchus caeruleonothus sp. nov. is described from 17 specimens collected off western and far northern Australia, between the Monte Bello Islands, Western Australia and Torres Strait, Queensland. It has also been confirmed outside this range by photographs taken at Ningaloo Reef and Exmouth Gulf, Western Australia, and at Claremont Isles and Lizard Island, Queensland. The new species is unique among the genus in having a combination of dorsal-fin rays XII, 18-20, lateral-line scales 56-61, gill rakers 7-9 on the upper limb and 18-20 on the lower limb of the first arch, nostrils minute, and fresh colouration in adults including body uniformly grey, cheek, opercles and posterior margin of the opercular membrane uniformly blue-grey, and rim of orbit and upper edge of maxilla dusky yellow. In contrast to its closest congeners, the juveniles have a distinctive pattern of narrow creamish-white to pale grey stripes on a dark grey to chocolate brown background on the head and body, and oblique dark stripes progressing with growth to spots on the caudal fin. Plectorhinchus unicolor (Macleay, 1883) from Japan to northern Australia is resurrected from the synonomy of P. schotaf and redescribed on the basis of the holotype and 24 non-type specimens. Plectorhinchus unicolor is most similar to P. schotaf, but can be distinguished by fresh colouration, modal dorsal and pectoral-fin ray counts and DNA barcoding. Plectorhinchus schotaf appears to be restricted to the region from southeast Africa to the Arabian Sea, including the Red Sea and Persian Gulf. Plectorhinchus griseus (Cuvier in Cuvier & Valenciennes, 1830) from Indian and Sri Lankan Seas has previously been treated as a junior synonym of P. schotaf, but in accordance with Smith (1962), is here confirmed as a valid species, readily distinguished from the latter by a concavity in the lateral profile of the snout in adults, deep body and high soft dorsal-fin ray count. Comparison of the CO1 genetic marker utilised in DNA barcoding also resulted in significant genetic divergences between the new species, P. unicolor and their closest sampled congeners. Some behavioural observations are also presented for the species treated, including aggressive interactions between individuals of the new species, the likes of which have not previously been recorded among species of Plectorhinchus.

A taxonomic assessment and redescription of Polydactylus multiradiatus (Günther, 1860), with a synopsis of other Australian species in the genus (Perciformes : Polynemidae)

The taxonomic status of three nominal species of Polydactylus, viz. P. multiradiatus (Gunther, 1860), P. specularis (De Vis, 1883) and P. auratus McKay, 1970, is revised. A comparison of the type series of Polydactylus auratus and the original description of Polynemus specularis with the holotype of Polynemus multiradiatus and 63 additional specimens from northern Australia has shown them to be conspecific. Polydactylus multiradiatus is characterised by its: 7 (rarely 6 or 8) pectoral filaments, not extending to posterior tip of pectoral fin; 14–17 (modally 15) pectoral fin rays; 13–15 (modally 14) dorsal fin soft rays; 16–18 (modally 16) anal fin soft rays; 49–56 (modally 52) pored lateral line scales; 7 or 8 (modally 8) scale rows above lateral line and 14 or 15 (14) below; 11–14 (modally 12) gill rakers on upper limb, 15–20 (modally 17) on lower and 27–33 (modally 30) in total; and vomerine teeth present. A synopsis of other Australian Polydactylus species and a key to known Australian Polydactylus are provided. H.o et1

Description of a new species of Tomiyamichthys from Australia with a discussion of the generic name

Tomiyamichthys levisquama is described as a new species from the Northern Territory and Queensland, Australia from estuaries and soft bottom marine environments. It is distinctive in body and head shape, head coloration and by the absence of ctenoid scales on the body. It is compared with the related species Tomiyamichthys russus (Cantor 1849), which has ctenoid scales on the posterior part of the body. The validity of the name Tomiyamichthys over Flabelligobius is discussed, with both genera being described in the same paper, here accepting Tomiyamichthys as the appropriate name.