Zainal A. Muchlisin

Molecular evidence for co-occurring cryptic lineages within the Sepioteuthis cf. lessoniana species complex in the Indian and Indo-West Pacific Oceans

AbstractThe big-fin reef squid, Sepioteuthis cf. lessoniana (Lesson 1930), is an important commodity species within artisanal and near-shore fisheries in the Indian and Indo-Pacific regions. While there has been some genetic and physical evidence that supports the existence of a species complex within S. cf. lessoniana, these studies have been extremely limited in scope geographically. To clarify the extent of cryptic diversity within S. cf. lessoniana, this study examines phylogenetic relationships using mitochondrial genes (cytochrome oxidase c, 16s ribosomal RNA) and nuclear genes (rhodopsin, octopine dehydrogenase) from nearly 400 individuals sampled from throughout the Indian, Indo-Pacific, and Pacific Ocean portions of the range of this species. Phylogenetic analyses using maximum likelihood methods and Bayesian inference identified three distinct lineages with no clear geographic delineations or morphological discriminations. Phylogeographic structure analysis showed high levels of genetic connectivity in the most widespread lineage, lineage C and low levels of connectivity in lineage B. This study provides significant phylogenetic evidence for cryptic lineages within this complex and confirms that cryptic lineages of S. cf. lessoniana occur in sympatry at both small and large spatial scales. Furthermore, it suggests that two closely related co-occurring cryptic lineages have pronounced differences in population structure, implying that underlying differences in ecology and/or life history may facilitate co-occurrence. Further studies are needed to assess the range and extent of cryptic speciation throughout the distribution of this complex. This information is extremely useful as a starting point for future studies exploring the evolution of diversity within Sepioteuthis and can be used to guide fisheries management efforts.

Influence of cryoprotectants on abnormality and motility of baung (Mystus nemurus) spermatozoa after long-term cryopreservation☆

Study on the effect of cryoprotectants on abnormality and motility of baung, Mystus nemurus spermatozoa were evaluated using transmission and scanning electron microscopy. Four cryoprotectants, dmso, ethanol, methanol and glycerol at concentration of 10% were tested in triplicates. Three ml of fresh sperm which was diluted with 60 ml of ringer solution was added to each of twelve 5-ml vials containing of 0.50-ml of the cryoprotectants. The vials were placed in an icebox containing dry ice 5 min and then storage into container containing liquid nitrogen for 13 months. The effect of cryoprotectants on the spermatozoa abnormality and motility were significant (P<0.05). The spermatozoa abnormality was significantly lower in methanol (62.65%) compared with the other cryoprotectants. The spermatozoa motility was higher in methanol, but not significantly different with ethanol (P>0.05). It is a negative correlation between sperm motility and abnormality. Generally, higher abnormalities of spermatozoa resulted low motility.

Spawning seasons of Rasbora tawarensis (Pisces:Cyprinidae) in Lake Laut Tawar, Aceh Province,Indonesia

BackgroundRasbora tawarensis is an endemic freshwater fish in Lake Laut Tawar, Aceh Province, Indonesia. Unfortunately, its status is regarded as critical endangered with populations decreasing in recent years. To date no information on the spawning activities of the fish are available. Therefore, this study provides a contribution to the knowledge on reproductive biology of R. tawarensis especially on spawning seasons as well as basic information for conservation of the species.MethodsMonthly sampling was conducted from April 2008 to March 2009 by using selective gillnets. The gonadosomatic index, size composition and sex ratio were assessed. The gonadal development was evaluated based on macroscopic and microscopic examinations of the gonads.ResultsThe gonadosomatic index (GSI) varied between 6.65 to 18.16 in female and 4.94 to 8.56 for male. GSI of the female R. tawarensis was higher in March, September and December indicating the onset of reproductive seasons, the GSI and oocyte size being directly correlated with gonadal development stages. Although, a greater proportion of mature male than female was detected during the study, the sex ratio showed that the overall number of female was higher than male. The ovaries had multiple oocyte size classes at every stage of gonadal development, thus R. tawarensis can be classified as a group synchronous spawner or a fractional multiple spawner.ConclusionThe spawning seasons of R. tawarensis were three times a year and September being the peak of the reproductive season and the female was the predominant sex. This species is classified as a group synchronous spawner.

Growth performance and feed utilization of keureling (Tor tambra) fingerlings fed a formulated diet with different doses of vitamin E (alpha-tocopherol)

Abstract The objective of the present study was to determine the optimum dosage of vitamin E (alpha-tocopherol) in the diet of keureling, Tor tambra (Val.) fingerlings for optimal growth performance and feed utilization. Five doses of vitamin E were tested: 0 mg kg−1 feed (control); 150 mg kg−1 feed; 300 mg kg−1 feed; 450 mg kg−1 feed; 600 mg kg−1. The feed ratio was 5% body weight, which was delivered twice daily at 08:00 and 17:00 for 60 days. The results showed that higher growth performance, feeding conversion ratios, feed efficiency, protein retention, and protein digestibility were obtained at 600 mg kg−1 feed, but the value was not significantly different from the other doses. The optimal dose in terms of the hepatosomatic index and survival rate was 300 mg kg−1. Hence, it was concluded that the optimum, most economical dose of vitamin E supplement for keureling (T. tambra) was 150 mg kg−1 feed, because this value was not significantly different from the doses of 300 and 600 mg kg−1 feed.

DNA barcoding of freshwater fishes from Lake Laut Tawar, Aceh Province, Indonesia

Modern taxonomic work regularly employs internal anatomy, physiology, behaviour, genes, isozymes, geography, and morphological characters, which remain the cornerstone of taxonomic treatments (Ward et al. 2009). However, there are difficulties in relying primarily on morphology when attempting to identify fishes during various stages of their development for example larvae or when examining fragmentary-, partial-, or processed remains. Even when intact adult specimens are available, the morphological characters used to discern species can be so subtle that identification is difficult, even for trained taxonomists (Ward et al. 2009). It is well recognised that DNA-based identification system or commonly known as DNA barcoding (Floyd et al. 2002, Hebert et al. 2003a), can aid the resolution of the vast diversity of life with its millions of species (Hebert et al. 2003a, 2003b, Tautz et al. 2003). It has much to offer ACTA ICHTHYOLOGICA ET PISCATORIA (2013) 43 (1): 21–29 DOI: 10.3750/AIP2013.43.1.04

Exploration of Natural Cryoprotectants for Cryopreservation of African Catfish, Clarias gariepinus , Burchell 1822 (Pisces: Clariidae) Spermatozoa

Toxicity is a major limitation to successful spermatozoa cryopreservation of fish. Due to this problem, it is critical to find potential cryoprotectants which are more environmental-friendly, non-toxic, easily prepared, and available at affordable prices. Hence, the objective of the present study was to investigate several natural cryoprotectants for optimal cryopreservation of the African catfish, Clarias gariepinus, Burchell

Ichthyofauna of Tripa Peat Swamp Forest, Aceh province, Indonesia

The Tripa Peat Swamp Forest (TPSF) suffers from deforestation due to agriculture, this habitat degradation potentially has a negative impact on fish biodiversity and community assemblages. The objective of this study was to develop an inventory of the fish fauna, evaluate the spatial variation in assemblage structure, document alien species, and quantify the economic value of fish species found from the area. Fish assemblages from the main rivers and tributaries of TPSF were sampled on May to June 2013. A total of 764 individuals were sampled during the survey, constituting 34 families, 47 genera, and 73 species where 46 species are categorized as fish consumption, 17 have potential for aquaculture, and 10 species have potential for ornamental, and three are non native. Cyprinidae is the predominant fish family within the TPSF. Fish assemblages were generally characterized by small population size for each species and low similarity among sites, reflecting the distinctive nature of each sampling site.

Genetic variation and taxonomy of Rasbora group (Cyprinidae) from Lake Laut Tawar, Indonesia

There were three presumed form of Rasbora found in Lake Laut Tawar, i.e. Depik, Eas and Relo. However, their phylogenetic status was remaining unclear. For this purposes the genetic data were utilized to resolve the taxonomic ambiguity of Rasbora group in Lake Laut Tawar. Approximately 655-bp were amplified from the 5′ region of the mitochondrial cytochrome oxidase subunit I (cox1) gene using the primer pairs (Fish F1 and Fish R1). A total of 14 haplotype sequences were produced from the ingroup where haplotypes 1 to 8 were shared by Eas and Depik, and haplotypes 9 to 14 were belonging to Relo. The genetic divergence varied from 0.2 to 9.6% i.e. between Eas and Relo, 9.6% and between Depik and Relo, 9.5%. The genetic data strongly indicated that Eas and Depik should be regarded as the same species of Rasbora tawarensis.

Remarkably low genetic variation but high population differentiation in the climbing perch, Anabas testudineus (Anabantidae), based on the mtDNA control region

Anabas testudineus (Anabantidae) is an important food fish in Southeast Asia. We analyzed the mitochondrial DNA control region sequence data to evaluate the genetic variability and population structure of this species. Sixty specimens were collected from four populations in Sumatra and two populations in Peninsular Malaysia. We found a very low level of genetic variability, with five of the six populations exhibiting total absence of genetic variation. Based on analysis of molecular variance, 84.72% of the total variation was among populations and 15.28% within populations. A geographical division based on FST values indicated highly significant genetic differentiation among populations from the four drainage systems: Aceh, Sumatra Utara, Pulau Pinang, and Terengganu (FST ranging from 0.633 to 1.000). No phylogeographic relationships among populations were detected, despite the generation of four distinct clades in a neighbor-joining phylogenetic tree.

First report on introduced freshwater fishes in the waters of Aceh, Indonesia

First report on introduced freshwater fishes in the waters of Aceh, Indonesia There is a paucity of information regarding introduced freshwater fishes in Indonesian waters. Hence, the objective of the present study was to evaluate the distribution of introduced fishes in the waters in the vicinity of Aceh, Indonesia. Fish sampling was conducted in five regions of Aceh at 17 sampling locations from January to June 2008. The samples were evaluated based on the Global Invasive Species Database and current publications and reports. A total of 114 species were recorded during the survey, of which nine were shortlisted as introduced species. Moreover, one additional introduced species, Atractosteus spatula (Lacepède), was recorded in April 2011. Overall, ten species of introduced fishes were noted in Aceh waters; of these Oreochromis mossambicus (Peters), was the most widely distributed.