First record and further description of the Cape hagfish Myxine capensis(Myxinidae) off Mozambique, western Indian Ocean

The first record of the Cape hagfish Myxine capensis in Mozambican waters is reported based on a single 356 mm total length specimen taken by bottom trawl off Maputo, 25° 52·9' S; 34° 42·7' E - 25° 54·1' S; 34° 41·0' E, at depths from 557 to 564 m. This account also represents the northernmost record of a hagfish in the western Indian Ocean. Morphometric and meristic data are provided and compared with those of 27 specimens (including the holotype) caught off Namibia and South Africa.     

Small and overlooked: Phylogeny of the genus Trigonodactylus (Squamata: Gekkonidae), with the first record of Trigonodactylus arabicus from Jordan

Geckos of the genus Trigonodactylus are widely distributed in the sand deserts of the Arabian Peninsula. Three species of this genus are currently recognized, with a fourth one, Stenodactylus pulcher, which placement within Trigonodactylus has been tentatively suggested, but not yet confirmed. We present a phylogenetic analysis of the genus Trigonodactylus with new specimens collected in central Saudi Arabia and southern Jordan. New genetic data has been generated from three mitochondrial markers to investigate the phylogenetic relationships of all species of the genus and to assess the putative generic assignment of S. pulcher. Our results confirm that S. pulcher indeed belongs within Trigonodactylus, branching as a sister lineage to all other species of the genus. The new samples cluster within Trigonodactylus arabicus, thus confirming the genetic homogeneity of the species across its large and seemingly inhospitable range. The new specimen collected in southern Jordan represents the first record for the country and a considerable range extension to the northwest from all previously reported localities. Our findings and discovery of a new species for Jordan highlight the need of more field surveys to be carried out in the underexplored parts of Jordan and northern Saudi Arabia, as these places still hold a potential for new discoveries and are crucial for understating the biogeography of the Arabian herpetofauna.     

Length-weight relationships of three Clupeiformes species from the Southeast coast of India,Bay of Bengal,Eastern Indian Ocean

This study deals with the length-weight relationships (LWRs) of three commercially important marine fishes belonging to the family Clupeidae from the major landing centers in Tuticorin, Mandapam, Thondi, Nagapattinam and Chennai in southeast coast of India. Monthly sampling were done at the respected landing centers from June, 2018 to April, 2019 from the commercial trawlers (with cod-end mesh size of 25–35 mm) and gill netters (with different mesh size vary from 20 to 170 mm). The estimated ‘b’ values ranged from 3.1215 (Sardinella albella) to 3.1819 (Amblygaster clupeoides) and ‘a’ values varied from 0.0059 (A. clupeoides) to 0.0074 (S. albella). The study also provides a new maximum total length (TL_max) for two species A. clupeoides and Sardinella fimbriata.     

A new marine gobiid species of the genus Clariger Jordan & Snyder (Gobiidae, Teleostei) from Taiwan

A new species of Clariger Jordan & Snyder, 1901 was collected from northern Taiwan. The genus was previously known only from Japanese waters. This discovery is the first formal and southernmost record of these marine gobies from the waters of subtropical Taiwan. The new species, Clariger taiwanensissp. n., is distinguished from its congeners by a unique combination of features: (1) fin rays: dorsal-fin rays III, I/8; anal-fin rays modally I/8; and pectoral-fin rays modally 19 (2+16+1); (2) longitudinal dermal ridge on head with 6 barbels; and (3) specific coloration pattern: head and trunk dark brown with scattered pale spots and blotches; cheek, ventral portion of head sometimes pale with deep brown spots; pectoral-fin base with a dark brown band; and caudal fin mostly dark brown proximally and with alternating and irregular dark brown and pale bands distally. A diagnostic key to all nominal species from Japan and Taiwan is provided.     

First record of the Olive Ridley Turtle,Lepidochelys olivacea,in Iranian coastal waters (Testudines,Cheloniidae)

Abstract

Three specimens of the Olive Ridley Turtle (Lepidochelys olivacea) were collected in Guader (Gwatar) Bay in the Sea of Oman on 6 January, 1997. Two of them have been preserved for the Zoological Museum of Gorgan University. This is the first report of the Olive Ridley Turtle in Iranian coastal waters.     

Two new fossil genera and species of Cerocephalinae (Hymenoptera,Chalcidoidea, Pteromalidae), including the first record from the Eocene

Cerocephalinae (Chalcidoidea, Pteromalidae) is a small group of parasitoid wasps characterized by a number of derived diagnostic features. Their hosts are endophytic beetles. So far, 43 species of Cerocephalinae have been described, including one fossil species from the Miocene. In this study, we add two new genera and species from Baltic and Dominican amber to the fossil record. Tenuicornus dominicus gen. et sp. n. is the second genus described from Dominican amber, and Pteropilosa lailarabanorum gen. et sp. n., described from Baltic amber, represents the oldest record of the subfamily, pushing the minimum age of Cerocephalinae back to the Eocene. Diagnostic characters of both species are discussed in comparison with other Cerocephalinae. An updated key to extant and fossil Cerocephalinae is presented.     

First record of Lagocephalus laevigatus (Tetraodontiformes, Tetraodontidae) from Galician waters (north-west Spain), a northernmost occurrence in the north-east Atlantic Ocean

The first record of the smooth puffer Lagocephalus laevigatus from Galician waters (north-west Spain) is reported. Three possible mechanisms of introduction of the specimen are considered: natural displacement, the aquarist trade and transport in ballast water.     

Yihiella yeosuensis gen. et sp. nov. (suessiaceae,dinophyceae), a novel dinoflagellate isolated from the coastal waters of Korea

A small (7–11 μm long) dinoflagellate with thin amphiesmal plates was isolated into culture from a water sample collected in coastal waters of Yeosu, southern Korea, and examined by LM, SEM, and TEM, and molecular analyses. The hemispheric episome was smaller than the hyposome. The nucleus was oval and situated from the central to the episomal region of the cell. A large yellowish‐brown chloroplast was located at the end of the hyposome, and some small chloroplasts extended into the periphery of the episome. The dinoflagellate had a single elongated apical vesicle (EAV) and a type E eyespot, which are key characteristics of the family Suessiaceae. Unlike other genera in this family, it had two long furrow lines, one on the episome and the other on the hyposome, and encircling the dorsal, and lateral sides of the cell body. The pyrenoid lacked starch sheaths, but tubular invaginations into the pyrenoid matrix from the cytoplasm were observed. In the TEM, the dinoflagellate was observed to have cable‐like structures (CLSs) near the eyespot but so far not observed in other dinoflagellates. The SSU rDNA sequences examined were 1.2%–5.1% different from those of other genera in the family Suessiaceae, whereas the LSU (D1‐D3) rDNA sequences of this dinoflagellate were 15.1%–31.5% different. The dinoflagellate lacked a 51‐bp fragment in domain D2 of the LSU rDNA, but it had an ~100‐bp fragment in domain D2. This feature has been found previously only in the genera Leiocephalium and Polarella, two other genera of the Suessiaceae. The molecular phylogeny and sequence divergence based on SSU, and LSU rDNA indicate that the Korean dinoflagellate holds a taxonomically distinctive position and we consider it to be a new species in a new genus in the family Suessiaceae, named Yihiella yeosuensis gen. et sp. nov.     

Population structure,sex ratio and growth of the seabob shrimp Xiphopenaeus kroyeri (Decapoda,Penaeidae) from coastal waters of southern Brazil

This study evaluated the growth and population structure of Xiphopenaeus kroyeri in Babitonga Bay, southern Brazil. Monthly trawls were conducted from July 2010 through June 2011, using a shrimp boat outfitted with double-rig nets, at depths from 5 to 17 m. Differences from the expected 0.5 sex ratio were determined by applying a Binomial test. A von Bertalanffy growth model was used to estimate the individual growth, and longevity was calculated using its inverted formula. A total of 4,007 individuals were measured, including 1,106 juveniles (sexually immature) and 2,901 adults. Females predominated in the larger size classes. Males and females showed asymptotic lengths of 27.7 mm and 31.4 mm, growth constants of 0.0086 and 0.0070 per day, and longevities of 538 and 661 days, respectively. The predominance of females in larger size classes is the general rule in species of Penaeidae. The paradigm of latitudinal-effect does not appear to apply to seabob shrimp on the southern Brazilian coast, perhaps because of the small proportion of larger individuals, the occurrence of cryptic species, or the intense fishing pressure in this region. The longevity values are within the general range for species of Penaeidae. The higher estimates for longevity in populations at lower latitudes may have occurred because of the growth constants observed at these locations, resulting in overestimation of this parameter.     

A matter of size: the population structure of the smallest known living shark,Etmopterus perryi (Springer & Burgess, 1985), from deep waters off the Colombian Caribbean coast

The dwarf lanternshark (Etmopterus perryi) is the smallest known described shark, and practically no information has been available on this species since first described in the mid-1980s. Therefore, the aim of this work is to describe, for the first time, the population structure regarding dwarf lanternshark in the Colombian Caribbean Sea. During deep-water research surveys conducted along the Colombian Caribbean coast, 87 stations were sampled using the swept area method. A total of 153 dwarf lanternshark individuals were caught in depths ranging from 230 to 530 m. This information was used to describe the size structures, morphological measurements including length-at-weight relationship, length at maturity in females and the spatial distribution of mean length and biomass of the species. The lengths of individuals ranged from 78.02 to 289.00 mm total length (TL), which is a new record of maximum length for this species. The spatial distribution of mean lengths and biomass distributions show high abundances and high relative mean lengths in the northeast area off Santa Marta and the area northwest of Riohacha. The mean biomass density in the whole prospected area was 5.52 kg km⁻². Length at 50% maturity in females was estimated in 203 mm TL (95% C.I. : 190–214 mm). Deep-water elasmobranch species, such as the dwarf lantern shark, are expected to show extremely low resilience to fishing exploitation, even when they are not targeted by commercial fishing. Therefore, the information reported in this study can serve as a baseline upon which management measurements can be proposed for the conservation of this shark species.