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  1. Fulltext Using DNA Barcodes to Aid the Identification of Larval Fishes in Tropical Estuarine Waters (Malacca Straits, Malaysia)
    Chu C, Loh KH, Ng CC, Ooi AL, Konishi Y, Huang SP, et al.
    Zool Stud, 2019;58:e30.
    PMID: 31966331 DOI: 10.6620/ZS.2019.58-30
    Larval descriptions of tropical marine and coastal fishes are very few, and this taxonomic problem is further exacerbated by the high diversity of fish species in these waters. Nonetheless, accurate larval identification in ecological and early life history studies of larval fishes is crucial for fishery management and habitat protection. The present study aimed to evaluate the usefulness of DNA barcodes to support larval fish identification since conventional dichotomous keys based on morphological traits are not efficient due to the lack of larval traits and the rapid morphological changes during ontogeny. Our molecular analysis uncovered a total of 48 taxa (21 families) from the larval samples collected from the Klang Strait waters encompassing both spawning and nursery grounds of marine and estuarine fishes. Thirty-two (67%) of the larval taxa were identified at the species level, two taxa (4%) at the genus level, and 14 taxa (29%) at family level. The relatively low rate of species-level identification is not necessarily due to the DNA barcoding method per se, but a general lack of reference sequences for speciose and non- commercial fish families such as Gobiidae, Blenniidae, and Callionymidae. Larval morphology remains important in species diagnoses when molecular matches are ambiguous. A lower ethanol percentage (50%) for larva preservation is also useful to keep the body of larvae intact for morphological identification, and to preserve DNA for subsequent molecular analyses. The 10% Chelex resin used to extract DNA is also cost- effective for long term monitoring of larval fishes. Hence, the DNA barcoding method is an effective and easy way to aid the identification of estuarine larval fishes at the species level.
  2. Spiny but Subitaneous Eggs: Egg Morphology and Hatching in Acartia Copepods in the Tropics
    Nakajima R, Yoshida T, Sakaguchi SO, Othman BHR, Toda T
    Zool Stud, 2019;58:e5.
    PMID: 31966306 DOI: 10.6620/ZS.2019.58-05
    Egg surface ornamentation, egg production rates, and hatching success of two calanoid copepod species (Acartia pacifica and Acartia cf. erythraea) were examined in a tropical coral reef of Tioman Island, Malaysia, near the equator (2°N). All observed females of A. pacifica and A. cf. erythraea produced eggs with spines on the surface, either short or long, which are common in resting eggs in temperate ecosystems that hatch when environmental conditions are favorable or after a certain refractory period. However, all of these spiny eggs in the present study hatched within 48 hours when exposed to ambient seawater temperature, suggesting that they were subitaneous eggs. Such spine ornamentation has been thought to be an adaptive feature only for resting eggs to survive during egg dormancy, but the presence of spines on subitaneous eggs suggests further possible functions of these spines such as reducing the risks of ingestion by predators.
  3. Fulltext Population Structure of the Blue Swimmer Crab Portunus pelagicus in Coastal Areas of Malaysia Inferred from Microsatellites
    Chai CJ, Bin Esa Y, Ismail S, Kamarudin MS
    Zool Stud, 2017;56:e26.
    PMID: 31966225 DOI: 10.6620/ZS.2017.56-26
    Chuan Jian Chai, Yuzine Bin Esa, Muhammad Fadhil Syukri Ismail, and Mohd. Salleh Kamarudin (2017)Portunus pelagicus, distributed throughout the Indo-West Paci c region, is one of the large and edible species of blue swimmer crabs. Increasing demand for the frozen and canned crabmeat industry worldwide has now relied mainly on P. pelagicus which in turn generates splendid income for the fisherman communities. In the present study, the population genetic structure of P. pelagicus was examined using six pairs of microsatellite loci. A total of 87 crab samples were collected from five different coastal areas of Malaysia. Genomic DNA was extracted from each sample for polymerase chain reaction (PCR) amplification and fragment analysis. Four out of six microsatellite primers revealed polymorphic loci in P. pelagicus sampled. The number of alleles per locus in P. pelagicus ranged from 14 to 34. Microsatellites analyses indicated low levels of genetic differentiation among the P. pelagicus populations. The average observed heterozygosity (HO = 0.48) obtained was lower than the standard heterozygosity found in most marine populations (HO = 0.79). The high FIS values (mean FIS = 0.4756) and low FST values (mean FST = 0.0413) also suggested the existence of inbreeding among different populations of P. pelagicus. In conclusion, this study was able to shed light on the population structure of P. pelagicus in coastal areas of Malaysia.
  4. Fulltext The Diet of the Cave Nectar Bat (Eonycteris spelaea Dobson) Suggests it Pollinates Economically and Ecologically Significant Plants in Southern Cambodia
    Thavry H, Cappelle J, Bumrungsri S, Thona L, Furey NM
    Zool Stud, 2017;56:e17.
    PMID: 31966216 DOI: 10.6620/ZS.2017.56-17
    Hoem Thavry, Julien Cappelle, Sara Bumrungsri, Lim Thona, and Neil M. Furey (2017) The importance of the cave nectar bat Eonycteris spelaea as a pollinator of economically significant crops and ecologically important plant species is increasingly documented, although information on the plants visited by this widely distributed bat species is currently confined to Thailand and Peninsular Malaysia. We undertook a dietary study on E. spelaea by sampling faecal rain produced by a colony in Kampot, southern Cambodia each month for one year and identifying plant taxa visited by the bats by their pollen. Our results indicate the diet of E. spelaea in Cambodia includes at least 13 plant taxa, eight of which were identi ed to genus or species. Pollen of Sonneratia spp. and Musa spp. had the highest mean monthly frequency at 30.9% and 16.9% respectively, followed by Oroxylum indicum (11.3%), Bombax anceps (11.2%), Parkia spp. (9.8%), Durio zibethinus (6.3%), Ceiba pentandra (6.0%) and Eucalyptus spp. (0.3%). With one exception, all of the plant taxa recorded at our study site are also visited by the bat species in Peninsular Malaysia and Thailand, although their relative dietary contributions differ. This variation likely reflects local differences in the availability, proximity and flowering phenology of chiropterophilous plants between regions, but also suggests a reliance of Cambodian bats on species that ower continuously, coupled with periodic shifts to species that ower profusely for short periods. Only three signi cant colonies (> 1,000 bats) of cave-roosting pteropodids are currently known in Cambodia, all of which are in Kampot and threatened by bushmeat hunting and roost disturbance. We recommend public education and law enforcement e orts to conserve these colonies, not least because Kampot is the premier region for Cambodian durian and this crop depends on nectarivorous bats for fruit set. Protection of mangroves would also bene t durian farmers because these are an important resource for nectarivorous bat populations.
  5. Fulltext Growth, Diet Composition and Reproductive Biology of the Invasive Freshwater Fish Chevron snakehead Channa striata on a Subtropical Island
    Li KC, Shieh BS, Chiu YW, Huang DJ, Liang SH
    Zool Stud, 2016;55:e53.
    PMID: 31966198 DOI: 10.6620/ZS.2016.55-53
    Kuan-chung Li, Bao-sen Shieh, Yuh-wen Chiu, Da-ji Huang, and Shih-hsiung Liang (2016) The Chevron snakehead (Channa striata) has been invading Taiwan for over 30 years, and it is currently widely distributed across diverse aquatic habitats within the island. Due to its strong environmental adaptability and carnivorous diet, C. striata has caused great negative impacts to the biodiversity of native fishes and aquatic organisms in Taiwan. To effectively restrain its spatial distribution and population, the objective of this study was to investigate the growing conditions, diet composition, and reproductive biology of C. striata in the field. In total, 294 individuals were collected from wetlands, irrigation canals, streams, and reservoirs in southern Taiwan from September 2008 to December 2010. Among 272 sex-identified individuals, more females (164) were collected than males (108). The morphological differences between the sexes could not be distinguished by the 10 body measurements recorded. Diverse food items, including snails, odonates, fishes, amphibians, and reptiles, were identified in the stomachs of 35 individuals. The minimum body length of sexually mature C. striata females exhibited at a standard length of 24.5 cm (total length 28 cm). The appearance of mature oocytes were mainly observed from July to November in 2009 and from April to October in 2010. Greater absolute fecundity (oocyte/individual) was estimated in Taiwan for C. striata than in its original distribution range possibly due to less water level fluctuation in the sampling habitats of Taiwan. The relative fecundity (oocyte/g) for C. striata was considered lower but within the documented range in Taiwan when compared with its original habitat in Malaysia. To effectively manage C. striata in Taiwan, regionally eradiating young and adult individuals, especially during the reproductive season and educating people to stop releasing it in the wild are possible ways to restrain and control the further spread of this exotic fish in Taiwan.
  6. Fulltext Swimbladder Evolution of Longfin Herrings (Pristigasteridae, Teleostei)
    Lavoué S, Ratmuangkhwang S, Ho HC, Chen WJ, Azizah MNS
    Zool Stud, 2018;57:e39.
    PMID: 31966279 DOI: 10.6620/ZS.2018.57-39
    Sébastien Lavoué, Sahat Ratmuangkhwang, Hsuan-Ching Ho, Wei-Jen Chen, and Mohd Nor Siti Azizah (2018) Longfin herrings form a monophyletic, circumtropically distributed family of mostly marine teleost fishes, the Pristigasteridae (Clupeoidei), that includes 38 species classified into nine genera and three main lineages (the Pelloninae, Pristigasterinae, and the genus Ilisha). The external morphology and osteology of the Pristigasteridae provide only a few, sometimes conflicting, informative characters which makes it difficult to reconstruct their phylogeny, but their swimbladder (a visceral gas-filled chamber that has several important functions in the Teleostei) appears to be highly specialized and variable among species. In particular, the swimbladder of most Indo-West Pacific pristigasterid species exhibits one or paired post-coelomic extensions, whereas New World species do not. The presence of these extensions conflicts with the current systematic classification, as they are only found in subsets of different taxa. To examine this conflict, the most comprehensive molecular phylogenetic tree of the Pristigasteridae to date was built using six molecular markers and 21 species. This tree deeply disagreed with the current classification in that it indicated that the subfamilies Pelloninae and Pristigasterinae are not monophyletic and neither are the genera Ilisha, Pellona, and Opisthopterus. Using this tree to infer the evolution of the post-coelomic extensions, it was found that their absence is the ancestral condition in the Pristigasteridae. Indo-West Pacific species with post-coelomic extensions evolved later and form a monophyletic group, inside which species with only one extension form a monophyletic group. The consequences of our findings on the evolution and classification of Pristigasteridae are discussed. We suggest that only species of Pristigasteridae having one or paired post-coelomic extensions should be included in the genus Ilisha.
  7. Fulltext Two New Moray Eels of Genera Diaphenchelys and Gymnothorax (Anguilliformes: Muraenidae) from Taiwan and the Philippines
    Huang WC, Smith DG, Loh KH, Liao TY
    Zool Stud, 2021;60:e24.
    PMID: 34853614 DOI: 10.6620/ZS.2021.60-24
    Two new moray eels of the genera Diaphenchelys and Gymnothorax from Taiwan and the Philippines are described. Diaphenchelys laimospila sp. nov. is described based on two specimens that represent the third species and a new geographic record of the genus. It can be distinguished from the other two congeners by the number of cephalic sensory pores, vertebral formula, morphometric measurements, and the coloration pattern. Gymnothorax pseudokidako sp. nov. is a muraenid with a dark brown body covered by pale snowflake-like blotches. It differs from the most similar species Gymnothorax kidako (Temminck and Schlegel) by having a relatively short tail (50.5-53.0% vs. 52.9-56.4% of TL), more dentary teeth (17-26 vs. 16-20), fewer total vertebrae (134-139 vs. 137-143), and the absence of white margin on anal fin (vs. prominent white margin). These two new species were also confirmed by molecular analyses, the mitochondrial COI gene (593 bp) for D. laimospila, and the nuclear EGR3 gene (767 bp) for G. pseudokidako.
  8. Fulltext Classification and Morphology of Rhinocypha spp. (Odonata): A Comprehensive Taxonomic Study Within the Females
    Mamat N, Abu A, Yusoff NR
    Zool Stud, 2021;60:e47.
    PMID: 35003341 DOI: 10.6620/ZS.2021.60-47
    Studies on Odonata have gained attention worldwide as well as locally in Malaysia. Although there is a wealth of data available to be utilized for solving taxonomic problems, ecological and behavioural research areas are more favoured than taxonomy and systematics. Thus, there are confusions over how to correctly identify closely related and sympatric species, especially in female odonates. One such example is in the genus Rhinocypha. Consequently, the present study focuses on taxonomic work, employing multi-approaches in the form of morphological (morphological diagnostics, Field Emission Scanning Electron Microscope (FESEM) and geometric morphometric analysis), applying the molecular technique. Seventeen morphological characteristics were created to differentiate between the females of Rhinocypha spp. A FESEM was used on the female's ovipositor to focus on the anal appendages and sheathing valve (V3). Also, the phylogenetic patterns expressed by COI and 16S rRNA genes, and canonical variate analysis for the wing geometric morphometric revealed three clusters that supported the distinction of the Rhinocypha group. In summary, this study effectively developed an integrated approach of classic morphological and trendy molecular, combined with FESEM microscopy techniques, which provided corroborative evidence and resolved taxonomic uncertainties.
  9. Determining the Dietary Preferences of Wild Asian Elephants (Elephas maximus) in Taman Negara National Park, Malaysia Based on Sex and Age using trnL DNA Metabarcoding Analysis
    Abdullah-Fauzi NAF, Karuppannan KV, Mohd-Radzi NHS, Gani M, Mohd-Ridwan AR, Othman N, et al.
    Zool Stud, 2022;61:e60.
    PMID: 37007822 DOI: 10.6620/ZS.2022.61-60
    The world's largest terrestrial mammal, Asian elephants, are known to have enormous feeding needs. Several factors such as season, sex, age, and daily activities influence the amount of food required by an individual. Generally, captive elephants have a limited choice of food on a daily basis compared with that of elephants in the wild. Elephants in captivity are fed according to a prepared feeding schedule, whereas wild elephants are free to choose the type of plants that they consume in their natural habitat. In the past, ecological observations have been widely used to determine the diet of wild elephants. However, the molecular approach has never been carried out. In the present study, we aimed to; 1) identify the plant diet of wild Asian elephants in Taman Negara National Park (TNNP) according to their sex and age using high-throughput DNA metabarcoding; and 2) determine the dietary formulation of captive elephants based on the generated plant metabarcoding database. DNA was extracted from 24 individual fecal samples collected using noninvasive sampling techniques from TNNP and the National Elephant Conservation Centre (NECC) Kuala Gandah. Seven pooled samples from male adult, female adult, male subadult, female subadult, male juvenile, female juvenile, and captive elephants were amplified and sequenced targeting the trnL region (50-150 base pairs). The CLC Genomic Workbench and PAST 4.02 software were used for data analysis. In total, 24 orders, 41 families, 233 genera, and 306 species of plants were successfully detected in the diet of the Asian elephants. The most abundant plant genera consumed were Sporobolus (21.88%), Musa (21.48%), and Ficus (10.80%). Plant variation was lower in samples from male elephants than in those from female elephants. The plant species identified were correlated with the nutrient benefits required by elephants. Adults and subadults consumed more plant species than were consumed by juvenile elephants. However, there was no significant difference between ages and sexes. The findings of this study can be used as guidance by the Department of Wildlife and National Parks for the management of captive elephants, especially in NECC Kuala Gandah.
  10. Molecular Identification, Fatty Acid Profile and Trace Elements in a Stranded Fin Whale in Sabah (Borneo, Malaysia): Implications on Migration Routes and Trophic Ecology of Southern Fin Whales
    Madin J, Talaha NHM, Lal MTM, Ransangan J, Yoshida T, Gallagher JB
    Zool Stud, 2022;61:e79.
    PMID: 37007816 DOI: 10.6620/ZS.2022.61-79
    Fin whales are a cosmopolitan species found in the largest water masses of the world. In Malaysia, as well as other tropical countries in the Southeast Asian region, literature on fin whales is limited, and as a result, there is confusion regarding their distribution range in the region. This study utilizes the fresh tissue of the skin and blubber of a dead fin whale that was stranded in Sabah (Borneo, Malaysia) on the coast of the South China Sea to confirm the species identity, possible properties of the species' diet, and any trace element contamination. The DNA profile results confirmed that the whale belonged to Balaenoptera physalus. Further investigation of its cytochrome b gene sequence indicated that it was closely related to the southern fin whale (Balaenoptera physalus quoyi). This finding indicates that fin whales indeed migrate to warm tropical waters and that their continuous global distribution spans the equatorial region. The dominant fatty acids, such as C18:0, C16:1, C18:1N9T and C16:0 profiles, were consistent with the pelagic plankton diet that the whale would have had during its migration in the tropical waters of the South China Sea. The whales are likely pelagic feeders and thus need to be offshore, which would explain why they are rarely seen in shallow coastal areas during migration in these waters. The concentrations of K, Ca, Sc, Mg and Al ranged from 0.45 μg g-1 to 7.80 μg g-1, while Cr, Cd, As and Pb were either very low or could not be detected. This is consistent with concentrations of trace elements previously reported for other baleen whale genera from the Southern Ocean. Our study demonstrates the importance of the South China Sea as a migration route for the southern fin whale, since it is a rich food source with relatively low contaminant levels. The South China Sea is therefore well-suited to ensure these whales' survival during migration.
  11. A New Species of the Bengal Spined Anchovy Stolephorus from the Eastern Indian Ocean and Redescription of Stolephorus dubiosus Wongratana, 1983, with Comments on the Evolution of Prepelvic Scute Numbers within Stolephorus (Clupeiformes: Engraulidae)
    Hata H, Lavoué S, Motomura H
    Zool Stud, 2022;61:e58.
    PMID: 37007820 DOI: 10.6620/ZS.2022.61-58
    The Bengal Spined Anchovy, Stolephorus taurus sp. nov. is described from 21 specimens from the northern Bay of Bengal. The new species closely resembles Stolephorus dubiosus Wongratana, 1983, which is redescribed. Both species have a predorsal scute, spine on the pelvic scute, long maxilla posteriorly slightly short of or just reaching the posterior margin of the opercle, 25 or more gill rakers on the lower limb of the first gill arch, and double black lines on the dorsum posterior to the dorsal fin. However, the new species differs from S. dubiosus in having a longer pelvic fin with the posterior tip of the depressed fin beyond vertical through the dorsal-fin origin (vs. usually not reaching to vertical through dorsal-fin origin), longer pectoral fin, second dorsal-and third dorsal-fin rays, second anal-and third anal-fin rays, and greater interorbital width. Stolephorus taurus sp. nov. is closely related to Stolephorus baganensis Delsman, 1931 and S. dubiosus, although at least 2% mean p-distance divergence in the mitochondrial cytochrome c oxidase subunit I (COI) gene separates each of the three species. A phylogenetic reconstruction of the evolution of the number of prepelvic scutes within Stolephorus indicated that having six scutes was the most likely ancestral condition in the genus, and was later reduced in the evolution of Stolephorus to five or four scutes. One such reduction occurred recently in the lineage of Stolephorus taurus sp. nov.
  12. Fulltext Preliminary Taxonomic Survey and Molecular Documentation of Jellyfish Species (Cnidaria: Scyphozoa and Cubozoa) in Malaysia
    Rizman-Idid M, Farrah-Azwa AB, Chong VC
    Zool Stud, 2016;55:e35.
    PMID: 31966180 DOI: 10.6620/ZS.2016.55-35
    Mohammed Rizman-Idid, Abu Bakar Farrah-Azwa, and Ving Ching Chong (2016) Scientific enquiries into jellyfish blooms and associated problems are often deterred by the lack of taxonomical and ecological studies worldwide. Taxonomic difficulty is attributed to the high degree of morphological variations among and within species. To date, only two scyphozoan jellyfish species have been documented from field surveys in Malaysian waters, whereas another four Malaysian scyphozoan and two cubozoan jellyfish species have been mentioned in toxicological studies. None of these species have; however, been verified. This study thus aimed to document and resolves the uncertainty of earlier identified species in the region using morphology and molecular DNA sequencing. Jellyfish specimens were collected from Malaysian waters in the Straits of Malacca, South-China Sea and the Sulu-Sulawesi Sea over two years (June 2008 to October 2010), and their DNA sequences were compared with those from the Atlantic and Pacific regions. Ten scyphozoan and two cubozoan species were recorded in Malaysian waters (South China Sea and Straits of Malacca). These jellyfish included eight species from the order Rhizostomeae (Rhizostomatidae, Lobonematidae, Mastigiidae, Catostylidae and Cepheidae), two species from Semaestomeae (Pelagiidae and Cyaneidae) and two species from class Cubozoa; one from order Carybdeida (family Carukiidae) and another from order Chirodropida (family Chiropsalmidae). Molecular identification of species using phylogenetic approaches was based on DNA sequences of partial cytochrome oxidase I (COI), 16S and internal transcribed spacer (ITS1) regions. The COI phylogenetic tree of Cubozoa and Scyphozoa species from the Atlantic and Pacific regions showed distinct clustering of six Malaysian jellyfish species. However, most of the deeper divergences and relationships between the families were unresolved, which were also observed in the 16S and ITS1 phylogenetic trees. The Malaysian edible species Lobonemoides robustus, Rhopilema hispidum and Rhopilema esculentum were grouped within Rhizostomeae, whereas other scyphozoans showed phylogenetic affinities to Semaestomeae and Kolpophorae. Chrysaora and Cyanea appeared non-monophyletic; however their paraphyly was not confirmed. This study has provided the much needed baseline information on the taxonomy of Malaysian jellyfish species which have been substantiated by partial COI, 16S and ITS1 sequences. A total of 12 putative species of jellyfish were identified, which encompassed 12 genera.
  13. Mitophylogeny of Pangasiid Catfishes and its Taxonomic Implications for Pangasiidae and the Suborder Siluroidei
    Duong TY, Pham LTK, Le XTK, Nguyen NTT, Nor AM, Le TH
    Zool Stud, 2023;62:e48.
    PMID: 37965298 DOI: 10.6620/ZS.2023.62-48
    Pangasiidae (catfish order: Siluriformes) comprises 30 valid catfish species in four genera: Pangasius, Pangasianodon, Helicophagus, and Pseudolais. Their systematics are frequently revised due to the addition of newly described species. Although Pangasiidae is known to be a monophyletic family, the generic and phylogenetic relationships among the taxa are poorly resolved. This study characterized three newly obtained complete mitogenomes of Mekong River catfishes from Vietnam (Pangasius mekongensis, Pangasius krempfi, and Pangasianodon hypophthalmus), as well as the inter-and intrafamilial relationships of the Pangasiidae and catfish families in Siluroidei. The genomic features of their mitogenomes were similar to those of previously reported pangasiids, including all regulatory elements, extended terminal associated sequences (ETAS), and conserved sequence blocks (CSBs) (CSB-1, CSB-2, CSB-3, and CSBs, A to F) in the control region. A comprehensive phylogeny constructed from datasets of multiple 13 PCG sequences from 117 complete mitogenomes of 32 recognized siluriform families established Pangasiidae as monophyletic and a sister group of Austroglanididae. The [Pangasiidae + Austroglanididae] + (Ictaluridae + Cranoglanididae) + Ariidae] clade is a sister to the "Big Africa" major clade of Siluriformes. Furthermore, both phylogenies constructed from the single barcodes (83 partial cox1 and 80 partial cytB, respectively) clearly indicate genus relationships within Pangasiidae. Pangasianodon was monophyletic and a sister to the (Pangasius + Helicophagus + Pseudolais) group. Within the genus Pangasius, P. mekongensis was placed as a sister taxon to P. pangasius. Pangasius sanitwongsei was found to be related to and grouped with Pangasianodon, but in single-gene phylogenies, it was assigned to the Pangasius + Helicophagus + Pseudolais group. The datasets in this study are useful for studying pangasiid systematics, taxonomy and evolution.
  14. Taxonomic implications of geographical variation in Rhinolophus affinis (Chiroptera: Rhinolophidae) in mainland Southeast Asia
    Ith S, Bumrungsri S, Furey NM, Bates PJ, Wonglapsuwan M, Khan FAA, et al.
    Zool Stud, 2015;54:e31.
    PMID: 31966118 DOI: 10.1186/s40555-015-0109-8
    BACKGROUND: Rhinolophusaffinis sensu lato isdistributed throughout Southeast Asia. The taxonomic status of forms attributed to the species is unclear due to the limited sample size with incomplete datasets and the taxa have high variation in morphology and echolocation call frequency. The aim of the study was to evaluate the distribution and taxonomic status of the subspecific forms of R. affinis in mainland Southeast Asia using large sample size with multiple datasets, including morphological, acoustic, and genetic data, both to elucidate taxonomic relationships and to test for congruence between these datasets.

    RESULTS: Three morphological forms were confirmed within the region; two concur with previously recognized taxa, namely R.affinis macrurus andR.affinis superans,and are strongly supported by morphological and genetic data. The third form is morphologically distinct, but its taxonomic status remains unclear. It is probable that this third form represents a distinct taxonomic entity; however, more data are required to confirm this. R. a. macrurus is known from the north of peninsular Thailand, Cambodia, Myanmar, Laos, and Vietnam (Indochinese subregion); R. a. superans is found throughout the Thai-Malay Peninsula (Sundaic subregion); whilst the third form is presently known from east central Myanmar (Shan state) and lower northern Vietnam (Nghe An Province).

    CONCLUSIONS: Our results suggest that at least three morphological forms occur in mainland Southeast Asia including one form which appears to be new to science. Echolocation call data for R. affinis are not a robust taxonomic tool as it shows a significant degree of variation which is not explained or supported by genetic and morphological findings. This study highlights significant levels of morphological variation in mainland Southeast Asia and provides an essential basis for further studies aiming to understand the population genetics, phylogeography, and taxonomy of the species.

  15. Mitochondrial Markers Identify a Genetic Boundary of the Green Tiger Prawn (Penaeus semisulcatus) in the Indo-Pacific Ocean
    Halim SAAA, Othman AS, Akib NAM, Jamaludin NA, Esa Y, Nor SAM
    Zool Stud, 2021;60:e8.
    PMID: 34386093 DOI: 10.6620/ZS.2021.60-08
    A population genetics study of the commercially important Green Tiger Prawn (Penaeus semisulcatus) was conducted in the Indo-Pacific Ocean with a focus on the Indo-Malay Archipelago waters of the South China Sea (SCS), Sulu Sea (SLS), Celebes Sea (CLS) and the Strait of Malacca (SOM), the latter being the main waterway that connects the Indian Ocean with the Pacific Ocean. A 548-base-pair region of mitochondrial COI and 571 base pairs of the control region (CR) were analysed in 284 specimens from 15 locations. Genetic divergences (Tamura 3-parameter) for COI ranged from 0.1% to 7.2% and CR 2.3% to 21.7%, with Bagan Pasir (BGP) in central SOM being the most genetically different from other populations (COI: 3.3-4.2%; CR: 7.1-16.5%). All populations were differentiated into two lineages with a genetic break in the vicinity of BGP; Lineage I comprised populations south of this site (SCS, SLS, CLS and part of SOM) and Lineage II comprised populations north of BGP (part of the SOM). Specifically, most individuals of Bagan Pasir (BGP) and another site just south of it, Batu Pahat (BPT), clustered in Lineage I, while all SOM populations to the north of these sites clustered in Lineage II. The BGP population is believed to be a mixed gene pool between the two lineages. The results could be attributed to the fluctuations of Pleistocene sea levels and a possible influence of the One Fathom Bank in SOM. High genetic diversity was recorded, π (Lineage I: COI: 3.4%; CR: 7.4%) (Lineage II: COI: 3.8%; CR: 12.6%) and, h (Lineage I: COI: 0.81; CR: 1.0) (Lineage II: COI: 0.57; CR: 0.99). Demographic statistics revealed that both lineages underwent a sudden expansion and consequent stabilisation in genetic variability. The findings of this study have wide implications for fisheries in the Indo-Pacific. The increased sampling effort within a narrower geographical scale by the current study permitted a precise locality of the genetic break for this species within the Indo-Pacific Ocean to be identified. The substantial genetic diversity within both lineages should be considered in fishery management and aquaculture development programs of this species in this region.
  16. Morphological Description and Molecular Characterisation of Glyptothoa gen. nov., a Fish Parasitic Deep-sea Cymothoid (Crustacea: Isopoda) from the Indian Ocean, with Four Species, Including One New Species
    Helna AK, Aneesh PT, Kumar AB, Ohtsuka S
    Zool Stud, 2023;62:e51.
    PMID: 38046785 DOI: 10.6620/ZS.2023.62-51
    Glyptothoa sagara gen. and sp. nov. is described from the host fish Glyptophidium macropus Alcock, 1894 (Ophidiidae), at depths 300 to 650 metres from the southwest coast of India. The mitochondrial cytochrome c oxidase subunit I (COI) gene of the species was sequenced and compared with other closely related branchial cymothoid genera. Both morphological and molecular data corroborate the inclusion of this parasitic isopod as a new genus, and we describe Glyptothoa sagara gen. and sp. nov. The following combinations of characters characterise the genus: cephalon immersed in pereonite 1; dorsum vaulted; all coxae visible in dorsal view; coxae shorter than or as long as pereonites; pereonites 4-7 slightly decrease in width towards one side, slightly asymmetrical, lateral margins slightly constricted, in hunched side; relatively wide pleon, with large lateral gaps between pleonites; antennula narrowly separated by rostrum, slender, shorter than antenna; antenna with 13 articles, buccal cone obscuring antennal bases; brood pouch arising from coxae 1-4, 6; oostegite 1 bilobed; pleopods rami all simple, without proximomedial lamellar lobe, without folds or thickened ridges. The adult life stages, such as females (ovigerous and non-ovigerous), males and transitional stage of the new species are described. The species is currently known only from the type locality and the type host. The ecological remarks of the newly described taxon are also provided. The following species are transferred from Elthusa Schioedte and Meinert, 1884: Glyptothoa myripristae (Bruce, 1990) comb. nov., Glyptothoa propinqua (Richardson, 1904) comb. nov. and Glyptothoa caudata (Schioedte and Meinert, 1884) comb. nov.
  17. Fulltext Integrative Descriptions of Two New Macrobiotidae Species (Tardigrada: Eutardigrada: Macrobiotoidea) from French Guiana and Malaysian Borneo
    Stec D, Dudziak M, Michalczyk Ł
    Zool Stud, 2020;59:e23.
    PMID: 33262846 DOI: 10.6620/ZS.2020.59-23
    In this paper we describe two new tardigrade species, one representing the Macrobiotus hufelandi complex and the other from the Paramacrobiotus richtersi complex. The descriptions are based on a detailed morphological examination under light and scanning electron microscopy and analysis of four genetic markers (18S rRNA, 28S rRNA, ITS-2 and COI). Macrobiotus crustulus sp. nov. from French Guiana is the most similar to Macrobiotus martini Bartels, Pilato, Lisi and Nelson, 2009, Macrobiotus santoroi Pilato and D'Urso, 1976, but differs from them mainly by having the lissostomus type of the oral cavity armature (teeth not visible under light microscopy) and well-developed, convex terminal discs of egg processes covered with evident granulation. Paramacrobiotus filipi sp. nov. from the Malaysian part of Borneo is the most similar to Paramacrobiotus alekseevi (Tumanov, 2005), but differs from it primarily by the presence of body granulation visible under light microscopy as well as sculptured and porous areoles around egg processes.
  18. Fulltext Taxonomy, Evolutionary and Dispersal Events of Pig-Tailed Macaque, Macaca nemestrina (Linnaeus, 1766) in Southeast Asia with Description of a New Subspecies, Macaca nemestrina perakensis in Malaysia
    Abdul-Latiff MAB, Md-Zain BM
    Zool Stud, 2021;60:e50.
    PMID: 35003344 DOI: 10.6620/ZS.2021.60-50
    The pig-tailed macaque, Macaca nemestrina, which is distributed in Peninsular Malaysia, Thailand, Borneo, and Sumatra, has been the subject of unstable and changing taxonomic entity in the M. nemestrina group. This species is involved with a human-macaque conflict in Malaysia and at the same time played an important role in the ethnozoological culture of Malaysian. Even so, comprehensive phylogenetic, population genetics and biogeographical analysis of M. nemestrina in Malaysia are non-existent after decades of intensive research on the genus itself. Thus, we conducted the first comprehensive genetic study of M. nemestrina in Malaysia, based on three mitochondrial loci-Cytochrome b (567 bp), D-loop (398 bp), and COI (577 bp)-from 27 individuals representing Malaysia, plus an additional 26 sequences of Southeast Asian macaques from Genbank. Comparative biogeographical analysis in this study supports the positions of M. nemestrina in M. nemestrina groups as opposed to the silenus or Sulawesi groups. Results from this study also indicate that Bornean populations are the first extant lineages to separate from the other examined lineages of M. nemestrina, M. leonina, M. pagensis, and M. siberu in Southeast Asia. Molecular clock analysis suggested that M. nemestrina arrived in the Malay Peninsula about 0.32 million years ago (MYA). Our results indicate that the population of pig-tailed macaque from Perak (west Peninsular Malaysia) differs genetically based on all phylogenetic and population genetic analyses. Morphologically, Perak's pig-tailed macaque shows brighter coloration than M. n. nemestrina. Thus, we proposed a new subspecies for Perak's pig-tailed macaque as Macaca nemestrina perakensis distributed in the state of Perak, Peninsular Malaysia. This research helps resolve the taxonomic position and population genetics of pig-tailed macaque in Malaysia, which contribute directly to conservation and management of the species in Malaysia.
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