Amirrudin Ahmad

The Population Size and Movement of Coastal Horseshoe Crab, Tachypleus gigas (Müller) on the East Coast of Peninsular Malaysia

Horseshoe crabs have recently gained popularity as new exotic delicacies in Malaysia, especially in Johor. It has been reported and claimed by some fishermen that horseshoe crabs, particularly females, are being transported in bulk to Thailand. This claim has sparked interest to identify population size and study the behaviour of horseshoe crabs along the east coast of Peninsular Malaysia in an attempt to determine the effect of this demand on the existing population. A study was carried out from December 2011 to March 2012 to determine the coastal horseshoe crab Tachypleus gigas population size in Chendor and Cherating, Pahang, about 10 km apart on the east coast of Peninsular Malaysia, using a Capture-Mark-Recapture method. The sampling was carried out three times at both sites. The population size was calculated using Bailey’s Triple Catch formula with the assumption of an open population. The horseshoe crabs’ ‘traveling distance’ was also determined by attaching numbered, white button tags, each bearing the researcher’s phone number, to a total of 99 horseshoe crab individuals (61 in Chendor, 38 in Cherating). The total estimated populations were 7,140 in Chendor and 9,900 in Cherating. The two populations were found to be interchangeable as the tagged animals from Chendor were recaptured in Cherating and vice versa, thus confirming emigration and immigration. About 25 % of tagged animals were recaptured in various places (at Chendor, Cherating and also outside both locations) as reported by fishermen. Animals tagged in Cherating were caught in a few locations in Pahang, including Tanjung Lumpur which is more than 50 km to the south. Most recaptures (40 %) were from different locations remote from the site where the horseshoe crabs were tagged and released. This study is on-going and notifications are still expected regarding the future location of the tagged animals.

The first riparian skink (Genus: Sphenomorphus Strauch, 1887) from Peninsular Malaysia and its relationship to other Indochinese and Sundaic species

Recently discovered populations of skinks of the genus Sphenomorphus from central Peninsular Malaysia represent a new species, S. sungaicolus sp. nov., and the first riparian skink known from Peninsular Malaysia. Morphological analyses of an earlier specimen reported as S. tersus from the Forest Research Institute of Malaysia (FRIM), Selangor indicate that it too is the new riparian species S. sungaicolus sp. nov. Additionally, two specimens from the Tembat Forest Reserve, Hulu Terengganu, Kelantan and another from Ulu Gombak, Selangor have been diagnosed as new the species. The latter specimen remained unidentified in the Bernice Pauahi Bishop Museum, Honolulu, Hawaii since its collection in June 1962. Morphological and molecular analyses demonstrate that S. sungaicolus sp. nov. forms a clade with the Indochinese species S. maculatus, S. indicus, and S. tersus and is the sister species of the latter. Sphenomorphus sungaicolus sp. nov. can be differentiated from all other members of this clade by having a smaller SVL (66.5-89.6 mm); 39-44 midbody scale rows; 72-81 paravertebral scales; 74-86 ventral scales; a primitive plantar scale arrangement; and 20-22 scale rows around the tail at the position of the 10th subcaudal.

On the taxonomy and phylogeny of the skinks Lipinia sekayuensis Grismer, Ismail, Awang, Rizal, & Ahmad and Lipinia surda Boulenger from Peninsular Malaysia

An integrative taxonomic analysis based on additional specimens and color photographs of Lipinia sekayuensis and additional color photographs of L. surda from Pulau Tioman and the Gunung Panti Forest Reserve, Peninsular Malaysia confirm the previous hypotheses that L. sekayuensis is a valid species and is the sister species of L. surda. The two species share a 12.8% sequence divergence between them.

A new species of lowland skink (genus Lipinia Gray, 1845) from northeastern Peninsular Malaysia

A new species of scincid lizard, Lipinia sekayuensis sp. nov. from Hutan Lipur Sekayu, Terengganu State in northeastern Peninsular Malaysia is most similar to L. surda (Boulenger) but differentiated from it and all other species of Lipinia by having the combination of an adult SVL of 42.3 mm; six supralabials; five infralabials; four supraoculars; prefrontals widely separated; two loreals; fused frontoparietals; lower eyelids bearing a large, transparent disc; 21 midbody scale rows; 56 paravertertebral scale rows; 65 ventral scale rows; enlarged, precloacal scales; 10 subdigital lamellae on the third finger; 11, 15, and seven lamellae on the third, fourth, and fifth toes, respectively; distal subdigital lamellae keeled; a median row of slightly enlarged, subcaudal scales present; a generally unicolor, dark-brown dorsum bearing nine very faint, diffuse, darker stripes; and an external ear opening replaced by a scaly, auditory depression.

Species Richness Estimation of Reptiles in Selected Sites of Tasik Kenyir, Hulu Terengganu, Malaysia

The knowledge on the composition of reptile species at Tasik Kenyir and its vicinity is still lacking as there is no comprehensive checklist available to date. This study aimed to provide a checklist and to estimate the species richness of reptiles in recreational forests located at and around Tasik Kenyir, namely Sungai Buweh, Belukar Bukit, Sekayu, and Saok. Visual Encounter Survey (VES), pitfall trapping, and opportunistic survey methods were used in this study. From 46 sampling days between April 2015 and February 2016, a total of 118 individuals from 26 species, 19 genera and nine families of reptiles were successfully recorded. Almost half of the reptile species belongs to family Gekkonidae (42%), followed by Agamidae (23%) and Scincidae (11%). The most abundant species observed were Eutropis multifasciata (24%), Hemidactylus frenatus (16%) and Gekko monarchus (13%). Eleven of the recorded species are protected under Wildlife Conservation Act 2010 and nine species are listed as Least Concern by IUCN 2016. The number of species estimated by non-parametric estimators, Chao 1 and Chao 2 were 35 and 39 species respectively. The results from this study could be useful to monitor the impact of habitat changes and human disturbances at Tasik Kenyir and the neighbouring areas.

Vertical Stratification of Fruit-Feeding Butterflies in Tasik Kenyir

The diversity of fruit-feeding butterflies at different vertical stratification were studied in secondary forests in Tasik Kenyir areas using 20 baited traps at each site. This study aimed to determine the species diversity of fruit-feeding butterflies at different forest strata which included ground and canopy levels. A single rope technique was applied in 23-days sampling period and a slice of fermented pineapple was used as bait. A total of 307 individuals from 72 species and 8 subfamilies were documented. Species diversity was higher at ground level than canopy level with Shannon diversity index H′ = 3.51 and H′ = 3.03. Butterflies compositions at ground level have high diversity compared to canopy level. Besides that, the graph of rarefaction curve did not reach an asymptote at either level. The species richness might reach to equilibrium while the specimen of butterflies increases if the periods of sampling are extended.

Taxonomic revision of the genus Poropuntius (Teleostei: Cyprinidae) in Peninsular Malaysia

Up to three nominal species of the cyprinid fish genus Poropuntius (i.e. P. deauratus [Valenciennes in Cuvier Valenciennes 1842], P. normani [Smith 1931], and P. smedleyi [de Beaufort 1933]) have been reported to occur in Peninsular Malaysian freshwater ecosystems. However, low morphological differentiation among species of Poropuntius causes confusion and it is still unknown how many valid species of Poropuntius occur in this region. The goal of this study is to review the taxonomic status of Poropuntius in Peninsular Malaysia by using morphological and molecular characters. Principal Component Analysis (PCA) on a morphometric dataset including 281 specimens of Poropuntius from Peninsular Malaysia and P. normani from Thailand (type locality) failed to identify non-overlapping clusters within sampled specimens. A phylogenetic tree based on cytochrome oxidase subunit I (COI) showed intraspecific levels of genetic differentiation within Poropuntius of Peninsular Malaysia and the specimens of P. normani from Thailand form a monophyletic group. Our results strongly support the presence of only one species of Poropuntius in Peninsular Malaysia, P. normani. We demonstrate that P. smedleyi described from Johor, southern Peninsular Malaysia, is a junior synonym of P. normani. The previous reports of the presence of P. deauratus in Peninsular Malaysia are doubtful because this species was described from Vietnam where, in all evidence, it is endemic.

Two new Tytthoscincus Linkem, Diesmos, & Brown (Squamata; Scincidae) from Peninsular Malaysia and another case of microsyntopy between ecologically specialized, unrelated, leaf-litter species

Two new species of diminutive, sympatric, lowland, leaf-litter skinks of the genus Tytthoscincus Linkem, Diesmos Brown from the Sekayu region of Hulu Terengganu, Terengganu State in northeastern Peninsular Malaysia are described on the basis genetic and morphological data. One of the new species, T. monticolus sp. nov., was collected in a hilly riparian area along Sungai (=river) Bubu and is most closely related to an undescribed species from the Tembak Reservoir area. The other, T. keciktuek sp. nov. collected along Sungai Peres, is most closely related to T. perhentianensis Grismer, Wood, Grismer from Pulau (=island) Perhentian Besar. Sympatry and syntopy of multiple, specialized, unrelated, leaf-litter species of Tytthoscincus was previously only known from upland areas and these new species represent the first example of lowland of sympatry. More importantly, however, these endemic species add to a growing body of research and discoveries that continue to underscore the unrealized biodiversity of the riparian systems of Hulu Terengganu and the Sekayu region and their need for protection and continued study.

Species composition and richness of amphibians in logged forests at Hulu Terengganu, Peninsular Malaysia

A study was done to compare amphibian species composition and richness between a disturbed forest due to logging/dam construction and a 30-year old logged forest at Hulu Terengganu, Peninsular Malaysia. This study was conducted from August to October 2014, using drift fenced-pitfall traps. The upstream (UP) and downstream riverine area (DP) of a dam called Puah Dam (PD) represented the disturbed forest habitat, while Sg. Deka Wildlife Reserve (SDWR) represented a 30-year old regenerating logged forest. There were six amphibian species found at SDWR, while four species were recorded at UP and DP.

A new genus and new species for an unusual semi-terrestrial potamid crab (Decapoda: Brachyura) with a bilobed mandibular palp from Peninsular Malaysia

Potamid freshwater crabs are characterised by mandibular palps possessing three segments with the terminal lobe simple. A new genus and new species of semi-terrestrial crab, Gempala bilobata , is here described from Peninsular Malaysia that possesses a 3-segmented mandibular palp having a bilobed terminal segment, a hitherto unknown condition. In addition, the carapace of the new genus is unusually high. Comparisons with allied potamid genera from Malaysia are also made and the affinities of the genus discussed.