Midlateral Scales Research Articles

A new silverside, Doboatherina palauensis (Atheriniformes: Atherinidae) from the Palau Islands in the West Pacific

A new atherinid fish, Doboatherina palauensis, is described based on the holotype and 31 paratypes, 36–51 mm in standard length, collected from the marine lakes and outer lagoon in Mecherchar Island, Republic of Palau. The new species can be distinguished from all congeners by a short, blunt ascending process of the premaxilla (height about twice maximum width), premaxilla with a single lateral process, posterior upper margin of dentary with a small process, palatine toothed, no crenulation along posterior margin of lateral and predorsal scales, smaller eye (diameter 9.2–11% of standard length), 37–39 midlateral scales, 38–41 total vertebrae, narrower midlateral band (about 1/2 width of midlateral scale, its upper and lower margins not reaching to upper and lower margins of midlateral scale row at the level of anal-fin origin, respectively). The new species resembles Doboatherina aetholepis (Kimura, Iwatsuki and Yoshino 2002), Doboatherina bleekeri (Gunther 1861), Doboatherina valenciennei (Bleeker 1854) and Doboatherina woodwardi (Jordan and Starks 1901) in sharing a comparatively slender body in the genus Doboatherina. The former is distinguishable from D. aetholepis by having only a short spatular outgrowth on posterior margin of predorsal and/or interdorsal scales or almost lacking the outgrowth (vs. a long spatular outgrowth on posterior margin of most predorsal and interdorsal scales in D. aetholepis) and narrower midlateral band (lower margin not reaching to lower margin of midlateral scale row vs. reaching), from D. bleekeri and D. valenciennei by lacking crenulated lateral and predorsal scales (vs. having crenulated lateral and/or predorsal scales) and a single lateral process on premaxilla (vs. two processes), and from D. woodwardi by having lower ascending process (height about twice maximum width vs. three times) and a single lateral process on premaxilla (vs. two processes). Doboatherina bleekeri has more numerous total vertebrae (42–47) than D. palauensis (38–41).

Revision of the Garra species of the Hajar Mountains in Oman and the UnitedArab Emirates with the description of two new species (Teleostei: Cyprinidae).

The Garra species inhabiting the Hajar Mountains are revised and five species are recognised, two of which are newly species described herein. Garra barreimiae, from the United Arab Emirates (UAE) and Northern Oman, is distinguished from other Garra species in the Hajar Mountains by a strongly mottled flank pattern with individual or series of midlateral orange scales, a white dorsal-fin tip, an orange spot at the upper operculum, and more gill rakers on the lower limb of the first gill arch. Garra barreimiae shawkahensis is a synonym of G. barreimiae. Garra gallagheri, from the Wadi Bani Khalid drainage in Oman, is distinguished by flank-scale margins the same colour or slightly darker than the centre of the scales. Garra longipinnis, from the interior wadis in the Central Hajar Mountains in Oman, is distinguished by flank-scale margins being clearly darker than the centre of scales. The original description of G. longipinnis was based on a few individuals with very large fins, which are here considered aberrant. Garra shamal, new species, from the coastal drainages around Muscat in Oman, is distinguished by a strongly mottled flank pattern usually without orange midlateral scales, a white dorsal-fin tip, no orange spot at the upper operculum, and middle caudal-fin rays and membranes the same colour or slightly darker than the rest of the fins in colouration. Garra sharq, new species, from the Wadi Kabbah drainage and a few interior springs in Oman, is distinguished by a strongly mottled flank pattern with individual or series of orange midlateral scales, no orange spot at the upper opercle, and dorsal-fin tip and membranes between central caudal-fin rays the same colour as the rest of the fins. All five species are well differentiated genetically and form distinct mitochondrial clades with between 2.1 and 9.2% differences (p-distances) in the mitochondrial COI.

Description of four new species of freshwater gobies from the Black River drainage in China and Vietnam (Teleostei: Gobiidae).

Four new species of Rhinogobius Gill 1859 are described from the Black River drainage in China and Vietnam. Rhinogobius coccinella, new species, and R. nanophyllum, new species, are described from the Mengyejiang River in Yunnan, China. Rhinogobius coccinella is diagnosed by having the cheek and operculum with about 25 large dark spots and branchiostegal membrane unmarked; caudal-peduncle depth 11-12% SL; 1-5 predorsal scales; 27-30 midlateral scales; and 28 vertebrae. Rhinogobius nanophyllum is diagnosed by having the cheek, operculum and pectoral-fin base with about 90 indistinct white marks, caudal fin plain-colored, second dorsal fin magnified with a very broad dark gray median band and a broad white proximal band in males; caudal-peduncle length 22-25% SL and pectoral-fin length 21-24% SL in males; head width at operculum 53-58% HL in males, 58-61% HL in females; 0 predorsal scales; 8-10 branched rays in the second dorsal fin; 7-8 branched anal-fin rays; and 28 vertebrae. Rhinogobius ngutinhoceps, new species, is described from the Nam Na River in Lai Chau, Vietnam. It differs from all congeners by the presence of a supraotic pore β; cheek and operculum with about 65 dark marks and branchiostegal membrane unmarked in males; snout pointed; lower jaw conspicuously protruding; predorsal length 40-41% SL; 12-15 predorsal scales; and 29 vertebrae. Rhinogobius phuongae, new species, is described from the Nam Mu River in Lai Chau, Vietnam, and is diagnosed by having the cheek with about 25 indistinct dark spots and branchiostegal membrane with pale spots in males; operculum unmarked; flank plain-colored in males; a conspicuous black blotch between spines I and III of the first dorsal fin; unpaired fins with a very broad white distal band; pectoral-fin length 20-21% SL; 8-10 predorsal scales; 8-9 branched rays in the second dorsal fin; and 28 vertebrae. A key to the species of Rhinogobius occurring within the Red River drainage is given.

Generic assignment of Leuciscus kurui Bogutskaya from the upper Tigris drainage, and a replacement name for Alburnus kurui Mangit Yerli (Teleostei: Leuciscidae).

The generic position of Leuciscus kurui Bogutskaya, 1995 is reviewed through a comparison of morphological and molecular characters (COI). The molecular data place L. kurui in Alburnus, close to Alburnus timarensis from the Lake Van basin. Alburnus kurui (Bogutskaya) is distinguished from this species by lacking a ventral keel and possessing both a very low number of gill rakers and midlateral scales. Alburnus selcuklui, from the upper Tigris drainage, cannot be distinguished from the widespread A. sellal and is therefore treated as a synonym of this species. Alburnus kurui Mangit Yerli, 2018 is a junior secondary homonym of A. kurui (Bogutskaya, 1995) and A. carianorum is proposed as its replacement name. Several specimens of Alburnus caeruleus and Alburnus heckeli shared the same haplotypes as some A. sellal and therefore these species cannot always be distinguished by mitochondrial molecular characters. Alburnus caeruleus and A. heckeli are treated as valid species. Other individuals of A. caeruleus have haplotypes very different from A. sellal, and A. heckeli is well distinguished from A. sellal by having more gill rakers. The Lake Van basin as a separate freshwater ecoregion and the treatment of several species of Alburnus in synonymy of A. mento are discussed.

Redescription of Saurichthys madagascariensis Piveteau, 1945 (Actinopterygii, Early Triassic), with implications for the early saurichthyid morphotype

ABSTRACTRay-finned fishes of the Saurichthyidae radiated rapidly after the end-Permian mass extinction event and became important predators within Triassic marine and freshwater ecosystems. Despite their extensive fossil record, the early evolution of saurichthyids still remains obscure. In an attempt to address this problem, we restudied Saurichthys madagascariensis, a key species from the Early Triassic of Madagascar (maximum age range middle Dienerian–early Smithian according to the available biostratigraphic data discussed herein), on the basis of ∼160 specimens, including several new, nearly complete individuals. Saurichthys madagascariensis is a medium-sized (ca. 60 cm) saurichthyid with a well-ossified circumorbital series, a suborbital, an antoperculum, one pair of branchiostegal rays, all fins with segmented, branched lepidotrichia and fringing fulcra, and an extensive squamation consisting of specialized scales arranged in six longitudinal rows, with rhombic scales in between. A series of ‘L’-shaped ventrolateral scales may be apomorphic for the Madagascan species. Comparisons among early saurichthyids reveal some shared traits, based upon which we hypothesize that the primitive condition of Saurichthyidae includes (1) broad scutes along the dorsal and ventral midlines articulating with one another via a specialized ‘keel and groove articulation’; (2) high, anteriorly inclined flank scales subdivided by the lateral line sensory canal into a tuberculated dorsal and a vertically striated ventral portion; (3) posteriorly inclined ventrolateral scales; and (4) a 1:2 relationship between the mid-lateral scales and the neural arches. These data may help to resolve problems in phylogenetic studies concerning synapomorphies and convergences of saurichthyids with other taxa.Citation for this article: Kogan, I., and C. Romano. 2016. Redescription of Saurichthys madagascariensis Piveteau, 1945 (Actinopterygii, Early Triassic), with implications for the early saurichthyid morphotype. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2016.1151886.

Two new species ofSaurichthys(Actinopterygii: Saurichthyidae) from the Middle Triassic of Monte San Giorgio, Switzerland, with implications for character evolution in the genus

Saurichthys, characterized by a long slender body and an elongated rostrum, is one of the most iconic genera of Late Paleozoic–Early Mesozoic fishes. The genus was particularly speciose in the Triassic, with a global distribution in both marine and freshwater habitats. Here, we describe two new species from the Middle Triassic Besano Formation of Monte San Giorgio, Switzerland, Saurichthys breviabdominalis sp. nov. and Saurichthys rieppeli sp. nov. S. breviabdominalis is characterized by a proportionately long operculum, short abdominal region and rib-like mid-lateral scales, whereas S. rieppeli is divergent from other Middle Triassic saurichthyids in the block-like haemal arches, fringing fulcra on the pelvic and unpaired fins, and reduction of the squamation to a single row in the abdominal region. Phylogenetic analysis places S. rieppeli in a basal position relative to congeners from the Alpine Triassic, and supports previous hypotheses regarding the convergent evolution of reduced squamation within saurichthyids. S. breviabdominalis forms a monophyletic group with species from the same locality, suggesting divergence in sympatry. This finding has implications for our understanding of disparity and character evolution in saurichthyid fishes, as well as ecomorphological divergence and resource partitioning between closely related fishes in Triassic marine ecosystems. © 2015 The Linnean Society of London

Fuyuanperleidus dengi Geng et. al. 2012 (Osteichthyes, Actinopterygii) from the Middle Triassic of Yunnan Province, South China

Two well preserved specimens of Fuyuanperleidus dengi Geng et al., 2012 are described from the Upper Member of the Guanling Formation (Pelsonian, Anisian, Middle Triassic) in Luoping County, Yunnan Province, South China. The attribution to Perleidiformes is confirmed according to a combination of features such as the general skull pattern, with the large preoperculum showing a prominent infraorbital process, the maxilla with deep posterior region and a dentition made of long and stout peg-like teeth with an acuminate apex, the deep mid-lateral flank scales and the caudal fin with epaxial fin rays. However, this taxon shows an unique arrangement of the squamation (here considered as autapomorphy) given by the insertion of several scales in each vertical row posterior to the pelvic fin, just below the scales carrying the lateral line, when their depth decreases abruptly. Owing to this unique character, and in spite of the very recent description of this genus, the authors considered necessary the erection of a new family, Fuyuanperleididae offering also new insights on the evolutionary trends and morphological specializations of the “subholosteans”. A cladistic analysis of the well known perleidiformes, with this taxon included, supports a possible monophyly of the order, and matches well the paleobiogeographic relationships of the Gondwana fresh-water taxa. The specialized deep-bodied Gondwana and Tethyan perleidiformes are independently evolved, ascertained by the parsimony analysis.

Descriptions of two new silversides, Hypoatherina golanii and Hypoatherina lunata, from the Indo-West Pacific (Atheriniformes: Atherinidae)

Two new atherinid fishes, Hypoatherina golanii and Hypoatherina lunata, are described based on specimens collected from the wide range of the Indo-West Pacific. The former species is known from the Red Sea and was confused with Hypoatherina barnesi because it has a somewhat wide midlateral band and overlapping meristic counts. Hypoatherina golanii is distinguished from its congeners by the midlateral scales with an indented posterior margin, posterior margin of anterior predorsal scales with a spatular outgrowth, posterior margin of axillary scales without a distinct projection, and posterior end of maxilla not slanted downward. Hypoatherina lunata is distributed in the waters of southern Japan (Okinawa and Kagoshima prefectures) and Indonesia (North Sulawesi, Maluku, and Papua), but was confused with Hypoatherina woodwardi. Hypoatherina lunata is distinguished from its congeners in having a distinct crescent marking in front of the eye and the anus usually situated anterior to the tip of the pelvic fin.

Redescriptions of the Indo-Pacific atherinid fishes Atherinomorus forskalii, Atherinomorus lacunosus, and Atherinomorus pinguis

The Indo-Pacific marine atherinid fishes Atherinomorus forskalii (Ruppell, 1838), Atherinomorus lacunosus (Forster, 1801), and Atherinomorus pinguis (Lacepede, 1803) are redescribed as valid species based on the types and non-type specimens collected throughout the Indo-Pacific. They are similar to each other chiefly in having a wide midlateral band (almost the same or greater than the midlateral scale width), large mouth (posterior tip of upper jaw reaching to or beyond a vertical through anterior margin of pupil), and no distinct tubercle at the posterior end of the dentary. All three species are distinguishable from congeners by those characters. The three species have long been confused with each other or synonymized erroneously as a single species. Atherinomorus forskalii, known from the Red Sea and eastern Mediterranean, differs from Atherinomorus lacunosus and Atherinomorus pinguis in having conspicuous, large endopterygoid teeth, forming obvious tooth ridges. Atherinomorus lacunosus, widely distributed in almost the entire Indo-Pacific, from East Africa to Tonga, north to southern Japan, and south to northern Australia, differs from Atherinomorus pinguis in having a wider midlateral band (the lower margin reaching to almost the center of the fourth scale row at level of the anal fin origin vs. the lower margin reaching to the ventral end of the third scale row in Atherinomorus pinguis) and more numerous midlateral scales (40–44 vs. 38–41 in Atherinomorus pinguis). Atherina morrisi Jordan and Starks, 1906, Hepsetia pinguis mineri Nichols and Roemhild, 1951, Pranesus capricornensis Woodland, 1961, Pranesus maculatus Taylor, 1964, and Pranesus pinguis ruppelli Smith, 1965, are regarded as junior synonyms of Atherinomorus lacunosus. Atherinomorus pinguis is also widely distributed in the Indo-West Pacific, from East Africa to northern Australia and north to southern Japan. Atherina pectoralis Valenciennes, 1835, is considered a junior synonym of Atherinomorus pinguis.

A new silverside, Atherinomorus aetholepis sp. nov., from the West Pacific (Atheriniformes: Atherinidae)

Atherinomorus aetholepis sp. nov. is described from the holotype and 51 paratypes, 44–72 mm in standard length, collected from Indonesian and Philippine waters. The species is similar to other congeners in general body appearance, especially A. duodecimalis and A. regina, in having a slender body, a tubercle on the posterior end of the dentary, and a narrow midlateral band, but clearly differing from them in having a long spatular outgrowth on the posterior margins of most of the predorsal and interdorsal scales. Additionally, the species differs from A. duodecimalis in having a more slender body [body depth 17–22 (mean 19) % SL vs. 19–25 (mean 22) % SL], more midlateral scales [37–40 (mean 38.4) vs. 35–38 (mean 36.6)], more total vertebrae [38–42 (mean 39.9) vs. 36–40 (mean 38.0)], and fewer lower gill rakers [18–22 (mean 20.2) vs. 20–25 (mean 22.3)], and from A. regina in having more anal fin soft rays (12–14 vs. 9–10).

Validity of the atherinid fish, Atherinomorus vaigiensis (Quoy and Gaimard, 1825), with comments on its synonymy

The Australian marine atherinid fish, Atherinomorus vaigiensis (Quoy and Gaimard, 1825), having long been synonymized under A. lacunosus (Forster in Bloch and Schneider, 1801), is redescribed as a valid species based on the holotype and non-type specimens. Atherinomorus vaigiensis, known only from eastern and western Australia, differs from other congeners in lacking a distinct tubercle on the posterior end of the dentary and having the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, 12–15 anal fin soft rays, 24–28 lower gill rakers, 39–42 midlateral scales, and a narrow midlateral band (width about 2/3 to 5/6 that of midlateral scale at level of anal fin origin). Atherina cylindrica Valenciennes in Cuvier and Valenciennes, 1835 and Pranesus ogilbyi Whitely, 1930 are regarded as junior synonyms of Atherinomorus vaigiensis.

Redescriptions of the Indo-West Pacific atherinid fishes, Atherinomorus endrachtensis (Quoy and Gaimard, 1825) and A. duodecimalis (Valenciennes in Cuvier and Valenciennes, 1835)

The Indo-Pacific marine atherinid fishes, Atherinomorus endrachtensis (Quoy and Gaimard, 1825) and Atherinomorus duodecimalis (Valenciennes in Cuvier and Valenciennes, 1835), having long been confused with each other, are redescribed as valid species based on the types and nontype specimens collected from the eastern Indian Ocean and West Pacific. Atherinomorus endrachtensis, known from the Philippines, Palau, North Sulawesi and Maluku Is. (Indonesia), and New Guinea, differs from other congeners in lacking a tubercle on the dentary and having the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, usually 10–11 anal fin soft rays, 33–35 midlateral scales, a narrow midlateral band (ca. half midlateral scale width at anal fin origin), and 3 distinct longitudinal broken black lines laterally and ventrolaterally on the body. A lectotype is designated for Atherina lineata Gunther, 1872, regarded as a junior synonym of Atherinomorus endrachtensis. Atherinomorus duodecimalis, known from Sri Lanka, Thailand, Yaeyama Is. (Japan), the Philippines, Indonesia, New Guinea, Queensland (Australia), and New Caledonia, differs from other congeners in having a tubercle on the posterior end of the dentary, the posterior tip of the upper jaw not extending beyond a vertical through the anterior margin of the pupil, usually 12–13 anal fin soft rays, 35–38 midlateral scales, and a narrow midlateral band (ca. 1/2 or 3/4 midlateral scale width at anal fin origin). Atherina balabacensis Seale, 1910 is regarded as a junior synonym of Atherinomorus duodecimalis.

A Preliminary Survey of Dermatoglyphic Variation in the Lizard Genus Sceloporus

Scanning electron microscopy of the outer surface of midlateral scales of 51 species of Sceloporus (%3/4 of those now known), representing all 15 groups (as of Smith, 1939) of the genus, suggests that dermatoglyphics are of no apparent diagnostic value at higher taxonomic levels in the genus Sceloporus, but may be very useful at the subspecies, species and species-group levels. Microornamentation of scale surfaces is seemingly unidirectional in evolution. Three variables are useful in systematic considerations in Sceloporus: degree of concavity of Oberhautchen cell surfaces, degree of overlap of cell boundaries, and degree of loss of spinules and reduction of surface pits; cristae occur in those species with the greatest cell-surface cavitation. All species examined exhibit Oberhautchen cell boundaries, much the same in size and shape. Dense spinulation, flat cell surfaces and lack of imbrication are primitive character-states in Sceloporus. * ** Most of the recent contributions to the rapidly-growing body of literature on the squamate integument centers upon the morphology of the ecdysis cycle (summarized by Maderson et al., 1972) and the range of dermatoglyphic variation as revealed by scanning electron microscopy (SEM) of scattered samples from lizards and snakes (summarized by Stewart and Daniel, 1973). No attempt has hitherto been made to explore the systematic significance of dermatoglyphic (DG) variation in either a broad (higher category) or narrow (intrageneric) perspective. Because of the long-standing interest of one of us in the systematics of Sceloporus (e.g., Smith, 1939), and the current explosion of investigation in that topic, we have attempted a survey of variation among the some 70 species now recognized in this genus