Danionella translucida,a new genus and species of cyprinid fish from Burma,one of the smallest living vertebrates

Synopsis Danionella translucida, a new genus and species of danioin cyprinid fishes, is described from Burma. Females are mature at 10–11 mm standard length, and the largest known specimen is only 12 mm. Ripe eggs are few in number and relatively large, 0.4–0.6 mm in diameter. Adults are scaleless and largely transparent, with a complex pattern of large melanophores on the ventral surface of the abdomen. Specializations observed in skeletal preparations include the danioin notch in the medial surface of the mandibles; a large maxillo-mandibulary cartilage; a cartilage (epibranchial 5?) uniting the branchial arches 4 and 5; pharyngeal bones with a single row of 4 tricuspid teeth; and pectoral, pelvic, and caudal fins with fewer rays than reported or observed in any other members of the family Cyprinidae.     

Ecological guild evolution and the discovery of the world's smallest vertebrate

Living vertebrates vary drastically in body size, yet few taxa reach the extremely minute size of some frogs and teleost fish. Here we describe two new species of diminutive terrestrial frogs from the megadiverse hotspot island of New Guinea, one of which represents the smallest known vertebrate species, attaining an average body size of only 7.7 mm. Both new species are members of the recently described genus Paedophryne, the four species of which are all among the ten smallest known frog species, making Paedophryne the most diminutive genus of anurans. This discovery highlights intriguing ecological similarities among the numerous independent origins of diminutive anurans, suggesting that minute frogs are not mere oddities, but represent a previously unrecognized ecological guild.     

Description of a new Lake Tanganyikan cichlid fish of the genus Cyprichromis(Perciformes: Cichlidae) with a note on sexual dimorphism

Cyprichromis coloratus , a new cichlid species, is described based on 41 type specimens from the Zambian coast of Lake Tanganyika. It differs from Cyprichromis microlepidotus by having fewer scales in the longitudinal line (41–44 v . 59–70 in C. microlepidotus ) and upper lateral line (31–36 v . 47–59), from Cyprichromis leptosoma by more dorsal‐fin spines (14–15 v . 11–13 in C. leptosoma ) and longitudinal line scales (41–44 v . 38–40), from Cyprichromis pavo by fewer dorsal‐fin spines and soft rays (29–31, usually 30, in total v . 30–32, usually 31, in C. pavo ), and from Cyprichromis zonatus by shallower body depth [24·0–28·5 (26·4 ± 1·1)% of standard length v . 24·5–30·5 (28·4 ± 1·3)% in C. zonatus ] and smaller eye [eye length 25·2–30·9 (27·2 ± 1·1)% of head length v . 27·9–33·3 (30·2 ± 1·2)%]. The new species is also separable from C. microlepidotus , C. pavo and C. zonatus by absence of distinct small spots on the body ( v . pearl grey and yellowish small spots along scale rows on body at least in males of C. microlepidotus and C. pavo ), its distinct dichromatism (particularly on the caudal fin) between males of the same population ( v . dichromatism absent in C. zonatus ) and absence of vertical bands ( v . three or four distinct vertical bands beneath dorsal fin base in live males of C. zonatus ). Cyprichromis coloratus n. sp. also exhibits sexual dimorphism, females having a larger head and males having longer pelvic fin, differences which are discussed in relation to reproductive behaviour. A key to the five species of Cyprichromis is included. A lectotype is designated for Cyprichromis leptosoma .     

A remarkable new genus of leafhoppers (Hemiptera,Cicadellidae, Iassinae) from Southeast Asia

Tardrabassus pakneunensis, n. gen. & sp. is described and illustrated. The new genus shows morphological affinities to three leafhopper subfamilies, Tartessinae, Deltocephalinae, and Iassinae, but is tentatively placed in Iassinae based on the position of the ocelli, the reduced lateral frontal sutures, the leg chaetotaxy, and the structure of the male genitalia.     

Revision of the Southeast Asian millipede genus Orthomorpha Bollman, 1893, with the proposal of a new genus (Diplopoda, Polydesmida, Paradoxosomatidae)

The large genus Orthomorpha is rediagnosed and is shown to currently comprise 51 identifiable species ranging from northern Myanmar and Thailand in the Northwest to Lombok Island, Indonesia in the Southeast. Of them, 20 species have been revised and/or abundantly illustrated, based on a restudy of mostly type material; further 12 species are described as new: Orthomorpha atypicasp. n., Orthomorpha communissp. n., Orthomorpha isarankuraisp. n., Orthomorpha picturatasp. n., Orthomorpha similanensissp. n., Orthomorpha suberectasp. n., Orthomorpha tuberculiferasp. n.,Orthomorpha subtuberculiferasp. n. and Orthomorpha latitergasp. n., all from Thailand, as well as Orthomorpha elevatasp. n.,Orthomorpha spiniformissp. n. and Orthomorpha subelevatasp. n., from northern Malaysia. The type-species Orthomorpha beaumontii (Le Guillou, 1841) is redescribed in due detail from male material as well, actually being a senior subjective synonym of Orthomorpha spinala (Attems, 1932), syn. n. Two additional new synonymies are proposed: Orthomorpha rotundicollis (Attems, 1937) = Orthomorpha tuberculata (Attems, 1937), syn. n., and Orthomorpha butteli Carl, 1922 = Orthomorpha consocius Chamberlin, 1945, syn. n., the valid names to the left. All species have been keyed and all new and some especially widespread species have been mapped. Further six species, including two revised from type material, are still to be considered dubious, mostly because their paraterga appear to be too narrow to represent Orthomorpha species. A new genus, Orthomorphoidesgen. n., diagnosed versus Orthomorpha through only moderately well developed paraterga, coupled with a poorly bi- or trifid gonopod tip, with at least some of its apical prongs being short spines, is erected for two species: Orthomorpha setosus (Attems, 1937), the type-species, which is also revised from type material, and Orthomorpha exaratus (Attems, 1953), both comb. n. ex Orthomorpha.     

Phylogeny of the Southeast Asian freshwater fish genus Pangio (Cypriniformes; Cobitidae)

The genus Pangio is one of the most species-rich of the loach family Cobitidae and widespread across South and Southeast Asia. Its species diversity has never been studied under a clear phylogenetic approach, but four 'species-groups' were proposed according to the most obvious morphological characters. We present here phylogenetic analyses of the genus Pangio based on sequence data of the mitochondrial cytochrome b gene, the nuclear recombination-activating gene 1 (RAG 1) and a combined dataset of 109 specimens from 18 morphologically identified species across the whole distribution area of the genus. Our data reveal the existence of three major lineages within Pangio. Two of our major lineages were congruent with formerly proposed species-groups, the remaining two species-groups together formed the third major lineage; herein we refer to the lineages as to anguillaris-group, kuhlii-oblonga group and shelfordii-group. The application of a molecular clock dated the age of the three lineages to 33-29 million years. At the species level, our data suggest about 30 distinct lineages, indicating that there is a high number of undescribed species within Pangio. The use of Pangio to address biogeographic questions is demonstrated with the example of the shelfordii-group, which is distributed across Sundaland.     

Paraspinibarbus,a new genus of cyprinid fishes from the Red River basin

Paraspinibarbus, a new and monotypic genus, is erected forSpinibarbus macracanthus Pellegrin et Chevey, 1936, a cyprinid from the Red River basin. It is characterized by a procumbent predorsal spine and a very thick lower lip with a continuous postlabial groove.Balantiocheilus hekouensis Wu, 1977 is a junior subjective synonym ofParaspinibarbus macracanthus. A lectotype is designated forS. macracanthus.     

Stentorceps, a remarkable new genus of eucoilid (Hymenoptera) from Africa

Abstract. Stentorceps tubicen , a new genus and species of Eucoilidae from East Africa, is described and illustrated. The genus is characterized by the possession of large protrusions on the face, features previously unknown in the family. The genus is compared with other eucoilids and its systematic position is discussed.     

Diet and sexual dimorphism in the very catholic lizard genus,Leiocephalus of the Bahamas

Summary Over 5,000 prey items from specimens of Bahamian Leiocephalus lizards were measured and identified taxonomically. The diet in general consists mainly of arthropods, but much plant matter is also eaten, including flowers and buds as well as fruit. Lizards comprise about 2% of the diet by volume. Individuals inhabiting relatively small islands are more likely to have eaten plant matter than those from relatively large islands. Within the most widespread species (carinatus), sexual dimorphism in size is greater, the smaller the number of sympatric species in its structural habitat. Prey-size differences between differently sized Leiocephalus are greater, the greater the dimorphism. However, even the most dimorphic sexes take rather similar prey sizes. For all Bahamian species combined, the inverse correlation of sexual dimorphism with sympatric species is not as strong as an inverse correlation with latitude. We suggest that sexual selection on female size to increase the clutch size that can be carried may have affected sexual dimorphism in the genus.     

Review of the Indo-Pacific gobiid fish genus Lubricogobius, with description of a new species and a new genus for L. pumilus

The gobiid genus Lubricogobius Tanaka, distinctive in being scaleless, without sensory pores, but with sensory papillae on the head, consists of three small species (largest, 33.7 mm SL): the yellow L. exiguus Tanaka, type species, from Japan, with probable records from Taiwan and New Caledonia; L. ornatus Fourmanoir, orange with blue lines on the head, described from Vietnam, recorded from the Arafura Sea, and the range here extended to the Timor Sea and Northwest Shelf of Western Australia, Ryukyu Islands, and to New Caledonia; and L. dinah, a new species from Papua New Guinea and the Ryukyu Islands, white dorsally and abruptly orange-yellow ventrally, with 10–11 dorsal soft rays. L. pumilus Larson and Hoese, known from one 14.5-mm specimen from off Somalia, is referred to the new genus Larsonella. The new genus differs from Lubricogobius in having scales posteriorly on the body, a more slender body, depressed head, no pelvic frenum, the snout longer than orbit diameter, and a different pattern of sensory papillae on the head. Received: September 30, 1999 / Accepted: June 9, 2000     

A new genus and species of cyprinid fish (Actinopterygii,Cyprinidae) from the Arabian Peninsula,and its phylogenetic and zoogeographic affinities

Arabibarbus hadhrami, a new species of cyprinid fish from the Hadhramaut Province of Yemen, is described. It has modally 30 scales (29–32) in the lateral line, the wedge-shaped head is longer (27.8–32.5 % SL) and higher (15.5–18.4 % SL) than in its congeners. The body is slender and laterally flattened. The dorsal fin is high (26.5–32.4 % SL) and well ossified. The pectoral fins (19.9–23.9 % SL) and pelvic fins (16.8–19.8 % SL) are longer than in its congeners. Two closely related species, Arabibarbus arabicus and Arabibarbus grypus are re-described and compared to the new species. Based on morphological and molecular characters the new genus Arabibarbus is erected for these three species. It is characterised by medium to large body size, an ossified, smooth principal dorsal fin ray, eight branched dorsal and five branched anal fin rays, large shield-shaped scales with numerous parallel radii, a lateral line with 29 to 44 scales, pharyngeal teeth that are hooked at their tips, their count being 2.3.5–5.3.2 and the possession of two pairs of barbels. Arabibarbus hadhrami is the type species of the new genus. The phylogenetic position of the new genus is analysed, based on the mitochondrial cytochrome b gene. It is the sister taxon to the genus Carasobarbus Karaman, 1971 and closely related to Mesopotamichthys Karaman, 1971, Pterocapoeta Günther, 1902 and ‘Barbus’ reinii Günther, 1874. Arabibarbus probably colonised the Arabian Peninsula about 4 Ma ago, coming from the Tigris-Euphrates drainage in the East via Wādī ar Rimah/Wādī al Bā?in.     

Mechanics of the feeding action of a cyprinid fish

The pressures in the buccal cavities of Golden orfe (Idus idus) have been recorded as the fish took food from a tube connected to a pressure transducer. Pressures 50–105 cm water below the pressure of the surrounding water were recorded as the buccal cavity expanded to suck the food in. Calculations based on the dimensions of the muscles lead to the conclusion that the levatores hyoidei, sternohyoideus, rectus abdominis, epaxial trunk muscles and obliquus internus probably all had to exert almost their maximum isometric tensions, to produce the largest reductions of pressure. These muscles seem nicely balanced in strength for their functions in feeding.     

A new species of the Southeast Asian genus Opisthotropis (Serpentes: Colubridae: Natricinae) from western Hunan,China

A new species of natricine snake of the Southeast Asian genus Opisthotropis Günther,1872 is described from western Hunan Province of China based on both mitochondrial DNA and morphological data.The new species is morphologically most similar and genetically most closely related to O.cheni Zhao,1999 and O.latouchii (Boulenger,1899),but possesses considerable genetic divergence (p-distance 5.1％-16.7％) and can be differentiated from all other congeners by a combination of the following morphological characters:(1) body size large (total length 514-586 mm) and strongly built;(2) dorsal scale rows 17 throughout,feebly keeled anteriorly and moderately keeled posteriorly;(3) ventral scales 147-152,subcaudal scales 54-62;(4) preocular absent,Ioreal elongated and touching orbit;(5) supralabials 8-9,fifth and sixth entering obit;(6) anterior temporals short,length 1.74-2.04 times longer than width;(7) maxillary teeth subequal,28-30;(8) dorsal surface of head with distinct irregular yellow stripes and markings edged with ochre;(9) body with clear black and yellow longitudinal streaks,partly fused to several lighter patches or thicker stripes anteriorly;and (10) venter pale yellow,with asymmetric blackish speckles along outer margin.We present an updated diagnostic key to all members of the genus Opisthotropis,and recommendations on the ecological study for the group are provided.     

Developmental morphology of the cyprinid fish, Candidia barbatus

 Embryonic, larval, and juvenile development of a Taiwanese cyprinid fish, Candidia barbatus, is described from laboratory-reared specimens. The eggs, measuring 1.8–2.1 mm in diameter, were demersal, almost spherical in shape, transparent and unpigmented, with a pale yellow yolk and no oil globule. Hatching occurred 56–69 h after fertilization, the newly hatched larvae measuring 4.9–5.3 mm in body length (BL) with 25–26 + 13–14 = 39–40 myomeres. The yolk was completely absorbed at 7.6 mm BL. Notochord flexion was initiated at 6.8 mm BL and finished at 7.6 mm BL. Aggregate numbers of all fin rays were completed at 12 mm BL. Barbels on the upper jaw appeared near the corner of the mouth at 17 mm BL. Eggs of the species closely resembled those of its related cyprinid genera, Opsariichthys and Zacco. Larvae and juveniles of C. barbatus were similar to those of O. uncirostris subspp., Z. platypus, and Z. pachycephalus, but differed from the latter in the process of disappearance of the adipose finfold (postflexion larval stage), barbels on upper jaw (juvenile stage), and pigmentation on the lateral body surface (postflexion larval and juvenile stages). Although C. barbatus also differed from the Z. temminckii species' group [Z. temminckii and Zacco sp. (sensu Hosoya, 2002)] in having barbels, larvae and juveniles of the former showed more similarity to the latter species group than to O. uncirostris subspp., Z. platypus, and Z. pachycephalus, from the aspect of head and body pigmentation.     

A remarkable new genus and a new species of chewing louse (Phthiraptera,Ischnocera, Philopteridae) from Brazil

A new genus of chewing louse as Bobdalgleishia, and its type species Bobdalgleishia stephanophallus sp. n. (Phthiraptera) belonging to the Brueelia-complex (Ischnocera: Philopteridae) are described. Adults of the new species are fully described, illustrated and compared morphologically with the type species of Motmotnirmus Mey & Barker, 2014, which is its closest relative. The type host of Bobdalgleishia stephanophallus is a subspecies of the great jacamar Jacamerops aureus ridgwayi Todd, 1943, an endemic Amazonian bird distributed in northern Brazil, and the type locality is the State of Pará. Bobdalgleishia is a remarkable genus with unique morphological and chaetotaxic characters which readily separate it from other members of the Brueelia-complex, in particular by having the first two marginal temporal and ocular setae very long.     

Photoreceptors of a cyprinid fish,the roach: morphological and spectral characteristics

Summary Structure-function studies were undertaken on cones in the retina of the cyprinid fish, the roach,Rutilus rutilus, in order to provide a basis for analysis of colour information by post-receptoral neurones. Measurements were made with two main aims: (i) To determine by microspectrophotometry the absorbance spectra of the photopigments present within the retina, and correlate these with the morphological types of photoreceptor; (ii) To characterize the morphologies of the photoreceptors at both light and electron microscopical levels and determine their relative abundance in the retina. In addition to red-, green-, and blue-sensitive cones, an ultra-violet-sensitive photoreceptor has been found in a sub-population of miniature short single cones. Possible relevance of this finding to vertebrate vision is discussed.     

Mating system, sexual dimorphism, and the opportunity for sexual selection in a territorial ungulate

In mammals, species with high sexual size dimorphism tend tohave highly polygynous mating systems associated with high variancein male lifetime reproductive success (LRS), leading to a highopportunity for sexual selection. However, little informationis available for species with weak sexual size dimorphism. Ina long-term study population, we used parentage analysis basedon 21 microsatellite markers to describe, for the first time,variance in male lifetime breeding success (LBS) of roe deer,a territorial ungulate where males weigh less than 10% morethan females. LBS ranged from 0 to 14 (mean = 4.54, variance= 15.5), and its distribution was highly skewed, with only afew males obtaining high LBS and many males failing to breedor siring only one fawn. As predicted for polygynous specieswith low sexual size dimorphism, the standardized variance inmale LBS was low (I_m = 0.75) and was only slightly higher thanthe standardized variance in female LRS (I_f = 0.53), suggestinga low opportunity for sexual selection. The I_m value reportedhere for roe deer is much lower than values reported for highlydimorphic ungulates such as red deer (I_m > 3). We suggestthat, along a continuum of opportunity for sexual selection,roe deer occupy a position closer to monogamous and monomorphicterritorial ungulates than to highly polygynous, sexually dimorphicungulates with dominance rank–based mating systems suchas harems or roving mating systems.     

Siphonogobius nue, a new genus and species of gobiid fish from japan

A new genus and species of gobiid fish,Siphonogobius nue, based on 15 specimens, is described from temperate Pacific coasts of Japan. It is unique amongst gobioids in having a simple tube-like infraorbital canal extending below the eye and the oculoscapular canal between pores A' and L' without openings, except for the terminal pores and pore D. Although well-developed infraorbital canals occur in two other gobioid genera, the rhyacichthyidRhyacichthys and the gobiidLophiogobius, such are distinct from that ofSiphonogobius in having several branches and openings. Furthermore, the new taxon is distinguished from all other gobioids by the following combination of characters: first dorsal-fin spines 7–9 (usually 8); pectoral-fin rays 24–26, the upper 7–9 rays free from the fin membrane; pelvic frenum thick, robust and slightly emarginate posteriorly; scales small and cycloid, 87–96 in longitudinal series; vertebrae 14–15+19–20=33–34 (usually 14+20=34); P-V usually 3/I II II I I I 0/11; anal-fin pterygiophores anterior to the first haemal spine 3–4 (usually 3); a row of short fleshy flaps on the ventral surface of the head, extending from the lower edge of the preopercle to the chin; anterior nostril with a minute skin flap. Axial skeletal features indicated thatSiphonogobius is closely related to a group which includesAcanthogobius and its relatives.