Seven new Psechrus species are described from South East Asia: P. arietinus sp. nov.(♂♀, Vietnam), P. insulanus sp. nov.(♂, Thailand), P. ampullaceus sp. nov.(♂♀, Vietnam), P. omistes sp. nov.(♂, Indonesia, Sumatra), P. quasillus sp. nov.(♂♀, Malaysia, Borneo), P. huberi sp. nov.(♀, Philippines), and P. wade sp. nov.(♂, Philippines). For the following species, new records are listed and intraspecific variation is discussed and illustrated: P. libelti Kulczyński, 1908, P. norops Bayer, 2012, P. rani Wang & Yin, 2001, P. khammouan Jäger, 2007, P. luangprabang Jäger, 2007, P. jaegeri Bayer, 2012, P. obtectus Bayer, 2012, P. kenting Yoshida, 2009 and P. crepido Bayer, 2012, and Fecenia protensa Thorell, 1891. The latter species is recorded from Vietnam for the first time. P. norops, P. libelti and an unidentified Psechrus species from Baluno, Mindanao are for the first time characterised and illustrated by their pre-epigynes and pre-vulvae.
The Humpback whale tubercles have been studied for more than a decade. Tubercle Leading Edge (TLE) effectively reduces the separation bubble size and helps in delaying stall. They are very effective in case of low Reynolds number flows. The current Computational Fluid Dynamics (CFD) study is on NACA 4415 airfoil, at a Reynolds number 120,000. Two TLE shapes are tested on NACA 4415 airfoil. The tubercle designs implemented on the airfoil are sinusoidal and spherical. A parametric study is also carried out considering three amplitudes (0.025c, 0.05c and 0.075c), the wavelength (0.25c) is fixed. Structured mesh is utilized to generate grid and Transition SST turbulence model is used to capture the flow physics. Results clearly show spherical tubercles outperform sinusoidal tubercles. Furthermore experimental study considering spherical TLE is carried out at Reynolds number 200,000. The experimental results show that spherical TLE improve performance compared to clean airfoil.
The male, pupa and mature larva of Simulium (Asiosimulium) wanchaii Takaoka & Choochote, one of the four species of the small Oriental black fly subgenus Asiosimulium, are described for the first time based on samples collected from Thailand. The male S. (A.) wanchaii is characterized based on the enlarged hind basitarsus and the ventral plate which is much wider than long. The pupa and larva are characterized by the gill with 19 filaments and the deep postgenal cleft, respectively. Keys are provided to identify all the four species of the subgenus Asiosimulium for females, males, pupae and mature larvae.
A new genus and species of the subtribe Batrisina from western Sarawak, Bryantinus matangus gen. et sp. n., is described, illustrated, and compared with related taxa. In addition, examination of a small series of batrisine material from Thailand revealed a new country record for Cerochusa cilioceps Yin & Nomura, which was previously known only from the island of Hainan in southern China.
Mycomya Rondani specimens from the islands of South-East Asia, i.e. Malaysia, Indonesia and the Philippines, are revised. The paper includes a key to the Mycomya species of the South-East Asian islands. The following six new species are described: M. shimai sp. n. from Java, Indonesia, M. pongo sp. n. from Sabah, Malaysia, and M. apoensis sp. n., M. nakanishii sp. n., M. paraklossi sp. n. and M. yatai sp. n. from Mindanao, the Philippines. The holotypes of M. klossi Edwards from Borneo, Malaysia, and M. minutata Edwards from Sumatra, Indonesia, were examined and their genitalia are described. M. occultans (Winnertz) is recorded from Java, Indonesia.
A new species, Megatyrus femoralis sp. n., is described from the Koshi Zone, East Nepal, with major diagnostic features illustrated. Megatyrus masumotoi Nomura, Sakchoowong & Chanpaisaeng, originally described from southwestern Thailand, is recorded from the Noring Timur Mountain, West Malaysia. The above data extends the known range of Megatyrus about 1,200 km to the west, and 870 km to the south.
T. iban sp. nov. is described from the Lanjak Entimau Wildlife Sanctuary in Sarawak, Malaysian Borneo. Both sexes can be distinguished from all other species of Telosticta by the form of the antehumeral markings.
Three new species of Dasyrhicnoessa Hendel, 1934 and one of Pseudorhicnoessa Malloch, 1914 from the Indo-Pacific area are described and the male terminalia illustrated. Among these new species, Dasyrhicnoessa paradoxa sp. nov. and Pseudorhicnoessa longicerca sp. nov. are especially noteworthy for the morphological peculiarities of the male terminalia.
Haemonchus contortus is a highly pathogenic nematode parasite of sheep and goats. This work was conducted to investigate the population and host variations of the parasitic nematode H. contortus of sheep and goats from Malaysia and Yemen. Eight morphological characters were investigated, namely the total body length, cervical papillae, right spicule, left spicule, right barb, left barb, gubernaculum and cuticular ridge (synlophe) pattern. Statistical analysis showed the presence of morphological variation between populations of H. contortus from Malaysia and Yemen, with minor variation in the synlophe pattern of these isolates. Isolates from each country were grouped together in the scatterplots with no host isolation. Body, cervical papillae and spicule lengths were the most important characters that distinguished between populations of the two countries. This variation between Malaysia and Yemen may be attributed to geographical isolation and the possible presence of a different isolate of this worm in each country.
The direction that a snail (Mollusca: Gastropoda) coils, whether dextral (right-handed) or sinistral (left-handed), originates in early development but is most easily observed in the shell form of the adult. Here, we review recent progress in understanding snail chirality from genetic, developmental and ecological perspectives. In the few species that have been characterized, chirality is determined by a single genetic locus with delayed inheritance, which means that the genotype is expressed in the mother's offspring. Although research lags behind the studies of asymmetry in the mouse and nematode, attempts to isolate the loci involved in snail chirality have begun, with the final aim of understanding how the axis of left-right asymmetry is established. In nature, most snail taxa (>90%) are dextral, but sinistrality is known from mutant individuals, populations within dextral species, entirely sinistral species, genera and even families. Ordinarily, it is expected that strong frequency-dependent selection should act against the establishment of new chiral types because the chiral minority have difficulty finding a suitable mating partner (their genitalia are on the 'wrong' side). Mixed populations should therefore not persist. Intriguingly, however, a very few land snail species, notably the subgenus Amphidromus sensu stricto, not only appear to mate randomly between different chiral types, but also have a stable, within-population chiral dimorphism, which suggests the involvement of a balancing factor. At the other end of the spectrum, in many species, different chiral types are unable to mate and so could be reproductively isolated from one another. However, while empirical data, models and simulations have indicated that chiral reversal must sometimes occur, it is rarely likely to lead to so-called 'single-gene' speciation. Nevertheless, chiral reversal could still be a contributing factor to speciation (or to divergence after speciation) when reproductive character displacement is involved. Understanding the establishment of chirality, the preponderance of dextral species and the rare instances of stable dimorphism is an important target for future research. Since the genetics of chirality have been studied in only a few pulmonate species, we also urge that more taxa, especially those from the sea, should be investigated.
Tree snails of the subgenus Amphidromus s. str. are unusual because of the chiral dimorphism that exists in many species, with clockwise (dextrally) and counter-clockwise (sinistrally) coiled individuals co-occurring in the same population. Given that mating in snails is normally impeded when the two partners have opposite coil, positive frequency-dependent selection should prevent such dimorphism from persisting. We test the hypothesis that a strong population structure with little movement between tree-based demes may result in the fixation of coiling morphs at a very small spatial scale, but apparent dimorphism at all larger scales. To do so, we describe the spatial structure in a Malaysian population of A. inversus (Müller, 1774) with 36% dextrals. We marked almost 700 juvenile and adult snails in a piece of forest consisting of 92 separate trees, and recorded dispersal and the proportions of dextrals and sinistrals in all trees over a 7-day period. We observed frequent movement between trees (155 events), and found that no trees had snail populations with proportions of dextrals and sinistrals that were significantly different from random. Upon recapture 1 year later, almost two-thirds of the snails had moved away from their original tree. We conclude that population structure alone cannot stabilise the coil dimorphism in Amphidromus.
The manner in which a gastropod shell coils has long intrigued laypersons and scientists alike. In evolutionary biology, gastropod shells are among the best-studied palaeontological and neontological objects. A gastropod shell generally exhibits logarithmic spiral growth, right-handedness and coils tightly around a single axis. Atypical shell-coiling patterns (e.g. sinistroid growth, uncoiled whorls and multiple coiling axes), however, continue to be uncovered in nature. Here, we report another coiling strategy that is not only puzzling from an evolutionary perspective, but also hitherto unknown among shelled gastropods. The terrestrial gastropod Opisthostoma vermiculum sp. nov. generates a shell with: (i) four discernable coiling axes, (ii) body whorls that thrice detach and twice reattach to preceding whorls without any reference support, and (iii) detached whorls that coil around three secondary axes in addition to their primary teleoconch axis. As the coiling strategies of individuals were found to be generally consistent throughout, this species appears to possess an unorthodox but rigorously defined set of developmental instructions. Although the evolutionary origins of O. vermiculum and its shell's functional significance can be elucidated only once fossil intermediates and live individuals are found, its bewildering morphology suggests that we still lack an understanding of relationships between form and function in certain taxonomic groups.
The genus Cryptopsocus Li, 2002 is synonymized with Trichadenotecnum Enderlein, 1909. The type species of Crypto-psocus, T. cynostigmus (Li, 2002) n. comb., is considered to be a close relative of T. marginatum New & Thornton, 1976. These species cannot be assigned to any species group previously established in Trichadenotecnum so that the marginatum species group is here proposed for them. Three new species belonging to this species group are described: T. tigrinum and T. sharkeyi from Thailand and T. sabahense from Sabah, Malaysia. The phylogenetic position of the marginatum group is discussed using morphological data.
Canon Solovyev is a small genus belonging to the Parasa-complex of Limacacodidae. It is distributed from northern India to the Malayan Peninsula. The genus previously included two species: C. punica (Herrich-Schäffer) from the Indian region and C. eos Solovyev from Nepal. Canon punica is recorded from China (Yunnan), northern Thailand and Malaysia, but specimens from northern Thailand and probably those from China (Yunnan) represent a new species that is described herein: C. sripanae Pellinen and Solovyev, new species. Externally, C. sripanae is similar to other Canon species, but it differs from punica and eos in hindwing color and male genitalia. The moths studied were collected at UV and mixed lights. Genitalia of the male holotype and a male and female paratypes are figured. Nomenclature of this study is based on Solovyev (2014).
A new species, Busoniomimus umbellatus sp. nov. is described and illustrated from Malaysia. In addition the female of B. hainanensis Zhang & Li is described from China. A key is provided to males of this genus.
A new species of Larimichthys from Terengganu, east coast of Peninsular Malaysia is described from specimens collected from the fish landing port at Pulau Kambing, Kuala Terengganu. Larimichthys terengganui can be readily distinguished from other species of the genus by having an equally short pair of ventral limbs at the end of the gas bladder appendages, which do not extend lateral-ventrally to the lower half of the body wall, and fewer dorsal soft rays (29-32 vs. 31-36) and vertebrae (24 vs. 25-28). Larimichthys terengganui can be distinguished from L. polyactis and L. crocea by having a gill raker at the angle of first gill arch shorter than the gill filament. Furthermore, the second anal spine in L. terengganui is equal or slightly shorter than eye diameter (vs. shorter in L. polyactis); L. terengganui has 8-9 anal soft rays (vs. only 7 in L. pamoides). Snout length of L. terengganui is greater than eye diameter, whereas in L. crocea the snout is shorter than eye diameter. A key to species of Larimichthys is provided. All obtained specimens of the species were recorded from Terengganu waters, east coast of Peninsular Malaysia.
The taxonomy of poorly known Mesagraecia Ingrisch, 1998 is reviewed. A new species of Mesagraecia spine-headed katydid (Conocephalinae: Agraeciini) is described from Bukit Larut, Perak, Peninsular Malaysia: Mesagraecia larutensis sp. n. A key to species is also presented.