Zulfigar Yasin

Parasites of Blood Cockle (Anadara granosa Linnaeus, 1758) from the Straits of Malacca

ABSTRACT This is the first report on the parasites of blood cockle Anadara granosa from the Straits of Malacca. For a histopathological survey, samples were collected for 13 mo from 3 natural habitats: the west coast of Pulau Aman, Malaysia; the east coast of Banda Acheh; and the east coast of Lhokseumawe, Indonesia. After reviewing histological preparations, Nematopsis sp. was found in the connective tissue, gills, gonad, mantle, digestive glands, and foot; trematode sporocysts were identified in the gonads, stomach epithelium, mantle, digestive glands, and foot; and a turbellarian was observed in the stomach epithelium, gonads, digestive glands, mantle, and gills. Remarkable spatial differences were found in the parasitic communities of A. granosa of the Straits of Malacca; however, no apparent temporal variation in the prevalence of any parasite was evident. Nematopsis sp. infection was very common in A. granosa collected from Pulau Aman, with no clear host tissue damage. Trematode sporocysts were observed at all sites, and the gonads were completely lacking in some individuals as a result of infection. A turbellarian was detected without any evidence of pathological damage to the host. From the survey, only a trematode was detected as a potential threat to the natural stocks of A. granosa along the coasts of the Straits of Malacca. Further study should be carried out to identify the specific taxonomic affiliation of the parasites.

A comparison of some population density sampling techniques for biodiversity, conservation, and environmental impact studies

Twelve terrestrial and marine studies were conducted at various sites in Malaysia, Brazil, and the United States between April 1999 and February 2004. These data were analyzed using five density estimate techniques for stationary (non-motile) organisms including Stratified Random Sampling, Point-Center Quarter, Third Nearest Object, Weinberg, and Strong. The Strong method gave the most accurate density estimates of stationary animals and plants. Stratified Random Sampling ranked second best and the Third Nearest Object the third best. Belt or strip transects may be preferable but can be restrictive in some situations because of logistics and associated time constraints. Straight line measurements on reefs were 3–27% more accurate than reef slack line and reef contour measurements. Most study areas measured with the standardized Morisita index of dispersion were moderately aggregated. Results from the Third Nearest Object and Point-Center Quarter techniques indicate that the addition of more data to establish a density correction factor does not necessarily give more accurate estimates of density.

Evidence of geographical structuring in the Malaysian Snakehead, Channa striata based on partial segment of the CO1 gene.

Channa striata, locally known as “haruan”, is economically important in fisheries and aquaculture industries in several Asian countries. DNA sequencing, based on a partial segment of the Cytochrome oxidase c subunit 1 (CO1) gene, was used to determine genetic variation in C. striata samples from four different populations on the west coast of Peninsular Malaysia. The highest nucleotide and haplotype diversities were observed in the Linggi population (π = 0.0067, h = 0.835), and the lowest in the Timah Tasoh population (π = 0.0008, h = 0.286). Apart from Kajang-Linggi, which was insignificant, FST values were significant (p < 0.05) in all pairwise-population comparisons. Consequently, it is inferred that genetic structuring C. striata populations in this region was largely shaped by a common origin, with secondary influences from geographical factors and isolation.

Reproductive biology of blood cockle Anadara granosa (Bivalvia: Arcidae) in the northern region of the Strait of Malacca

A study on the reproductive cycle of the blood cockle Anadara granosa (Bivalvia: Arcidae) was conducted at three different areas in the northern region of the Strait of Malacca. A total of 1,920 samples of adult A. granosa (38–71 mm length) were collected from June 2009 until September 2010. Qualitative techniques (gonadal microscopic fresh smear test and histology analysis) as well as quantitative techniques (analysis of condition index and gonadal index) were used to predict monthly gonadal development stages of A. granosa. The gonadal index of A. granosa from Banda Aceh (Indonesia) (r = 0.469, P > 0.05) and Pulau Pinang (Malaysia) (r = 0.123, P > 0.05) did not show any correlation to their condition index, whereas the gonadal index of A. granosa from Lhokseumawe (Indonesia) (r = 0.609, P < 0.05) showed moderate positive correlation to the condition index. During the 16 month sampling period, four reproductive cycles were observed: each from three to six months. The process of releasing gametes is termed dribble spawning, and is the same in all populations. The principle component analysis (PCA) indicated that A. granosa reproduction was affected by interaction between internal physiological factors and indigenous environmental factors. In all sampling areas, phytoplankton density played a key role in the reproductive cycle in A. granosa. Information on the reproductive biology of this species is essential for species management and to improve the sustainability practices of the fisheries industry. These findings will provide basic information on the biology of the blood cockle A. granosa for stock management in the region.

Sea cucumbers of the genus Stichopus Brandt, 1835 (Holothuroidea, Stichopodidae) in Straits of Malacca with description of a new species

Abstract Five sea cucumber species including one new species of the genus Stichopus are reported from the shallow coral reefs of Straits of Malacca. The new species Stichopus fusiformiossa has unusual fusiform spicules in the tentacles, which are not found in the other species of the genus. Pseudo-tables and large perforated plates are newly recorded for Stichopus hermanni Semper, 1868 and Stichopus vastus Sluiter, 1887, respectively.

Systematics, genetics, and biogeography of intertidal mites (Acari, Oribatida) from the Andaman Sea and Strait of Malacca

Abstract This study demonstrates for the first time the presence of marine‐associated mites in the Andaman Sea and Strait of Malacca and reveals a relatively high diversity of these taxa with six species from two different families: Selenoribatidae and Fortuyniidae. Indopacifica, a new genus of Selenoribatidae, is described from Thailand and Malaysia, with two new species, Indopacifica pantai n. sp. and Indopacifica parva n. sp. The genus is characterized by the unique combination of following characters: lacking lamellar ridges, incomplete dorsosejugal suture, fourteen pairs of notogastral setae, and presence of epimeral foveae. A phylogenetic reconstruction based on 18S ribosomal RNA sequences clearly confirms the distinctness of the new genus Indopacifica and places it close to the genus Rhizophobates. The lack of molecular genetic data of possible relatives impedes a clear assessment, and hence, we emphasize the need for further combined approaches using morphological and molecular genetic sequence data. All species show wide distribution areas within this geographic region suggesting that these taxa are good dispersers despite their minute size and wingless body. Molecular genetic data demonstrate recent gene flow between far distant populations of I. pantai n. sp. from the coasts of Thailand and two islands of Malaysia and hence confirm this assumption. The seasonally changing surface currents within this geographic area may favor hydrochorous dispersal and hence genetic exchange. Nevertheless, morphometric data show a slight trend to morphological divergence among the studied populations, whereas this variation is suggested to be a result of genetic drift but also of habitat differences in one population of Alismobates pseudoreticulatus.

A taxonomic revision of the genus Apostichopus (Holothuroidea: Stichopodidae) from Japan

Complete redescriptions of sea cucumbers in the genus Apostichopus Liao, 1980 are provided using the type specimens and specimens deposited in the National Museum of Nature and Science, Tsukuba, Japan. The genus consists of A. armatus (Selenka, 1867) and A. japonicus (Selenka, 1867), which can be distinguished by some spicules in the dorsal body wall; the rim of reduced table spicules in A. armatus is spinous, while that in A. japonicus is smooth. Spicules from the tentacles, papillae, tube feet, and cloaca are similar for both species.

Research on the Biodiversity of the Seas Surrounding Malaysia

This chapter integrates the findings of reviews of the marine biodiversity of Malaysian waters, providing a perspective on what is known and the major scientific gaps. Although Malaysias seas are located at the worlds most diverse region, the number of studies on marine biodiversity is considered relatively limited as the result of lack of funding and experts for taxonomic work. Deep-sea habitats also have not been explored, and species-rich taxonomic groups, especially of smaller organisms, remain poorly studied. In this chapter, we discuss how collab- oration with international institutions is necessary to fill the knowledge gaps and improve the productivity and discovery of marine biodiversity in Malaysian waters.

Distribution and Biomass of Halophila ovalis (R. Brown) Hook. f. at Pulau Gazumbo, Penang, Straits of Malacca

* Corresponding author: Tel: +6046533500 Fax: +6046533500 Abstract Pulau Gazumbo is a small man-made island (14.25 km 2 ) located in the Straits of Malacca, however it has an extensive seagrass bed that mainly consist of Halophila ovalis surrounding the island and extend to the subtidal area. This paper aims to study the distribution and biomass of the dominant seagrass in the island after recolonization in 23-26 years. Three 50m transects parallel to the shore, i.e. nearshore, middle and offshore, were established at the flat intertidal area at the northeastern part of the island. For each transect, twelve 50 x 50cm quadrates and 0.0035 m 2 core were observed and collected for seagrass distribution and biomass data. H. ovalis were widely distributed at the offshore transect (1.5 km

Diversity of Family Fungiidae in Malaysian Waters

Diversity of the family Fungiidae was investigated in Malaysian waters during an expedition in 2004. From the samples collected on 18 reef locations around Malaysian waters, only 12 locations contained fungiid corals. From the locations that have fungiid corals, 11 species from five genera were recorded. They are Fungia (Ctenactis) echinata, Fungia (Ctenactis) simplex, Fungia (Danafungia scruposa, Fungia (Danafungia) danai, Fungia (Fungia) fungites, Fungia (Pleuractis) paumotensis, Fungia (Pleuractis) scutaria, Halomitra pileus, Sandalolitha robusta, Herpolitha limax and Polyphyllia talpina. The diversity of the fungiid corals at Hempasan Dang Ajar and Terumbu Peninjau far outweighs all other sites with six different species at each location. Other locations have three species on average. Out of 11 species of Fungiidae coral, Sandalolitha robusta and Herpolitha limax are the most commonly found species. They are found on seven sampling locations each. The rarest species are Fungia simplex, Fungia scruposa and Fungia paumotensis which can be found at only one sampling location each. Other available species could be found at three locations on average. This study has reported higher number of fungiid species compared to previous studies done in Peninsular Malaysia but similar with the study done in Singapore.