The Siamese crocodile (Crocodylus siamensis) and Saltwater crocodile (C. porosus) are two of the most endangered animals in Thailand. Their numbers have been reduced severely by hunting and habitat fragmentation. A reintroduction plan involving captive-bred populations that are used commercially is important and necessary as a conservation strategy to aid in the recovery of wild populations. Here, the genetic diversity and population structure of 69 individual crocodiles, mostly members of captive populations, were analyzed using both mitochondrial D-loop DNA and microsatellite markers. The overall haplotype diversity was 0.924–0.971 and the mean expected heterozygosity across 22 microsatellite loci was 0.578–0.701 for the two species. This agreed with the star-like shaped topology of the haplotype network, which suggests a high level of genetic diversity. The mean ratio of the number of alleles to the allelic range (M ratio) for the populations of both species was considerably lower than the threshold of 0.68, which was interpreted as indicative of a historical genetic bottleneck. Microsatellite markers provided evidence of introgression for three individual crocodiles, which suggest that hybridization might have occurred between C. siamensis and C. porosus. D-loop sequence analysis detected bi-directional hybridization between male and female individuals of the parent species. Therefore, identification of genetically non-hybrid and hybrid individuals is important for long-term conservation management. Relatedness values were low within the captive populations, which supported their genetic integrity and the viability of a breeding and reintroduction management plan. This work constitutes the first step in establishing an appropriate source population from a scientifically managed perspective for an in situ/ex situ conservation program and reintroduction of crocodile individuals to the wild in Thailand.

Defining species boundaries is important to address evolutionary questions and understand true biodiversity in a region. Determining the actual number of species is not trivial, and numerous species-delimitation algorithms have been developed and extensively applied to a wide range of organisms. The cosmopolitan red-algal genus Bostrychia has been used as a model system to study evolutionary processes, yet phylogeny within the genus and its true species composition are still unresolved. The four species B. arbuscula, B. gracilis, B. intricata and B. vaga represented a distinctive morphotype that was once the basis for segregation into the separate genus Stictosiphonia, and all appeared to be restricted to the Southern Hemisphere. We sequenced genes from all three genomes [plastid: rbcL; mitochondrial: cytochrome c oxidase subunit I(COI); and nuclear: large-subunit ribosomal RNA] to examine the phylogenetic relationships of the four species and to establish their diacritical features. Our phyloge...

Sex identification provides important information for ecological and evolutionary studies, as well as benefiting snake conservation management. Traditional methods such as cloacal probing or cloacal popping are counterproductive for sex identification concerning very small species, resulting in difficulties in the management of their breeding programs. In this study, the nucleotide sequences of gametologous genes (CTNNB1andWACgenes) were used for the development of molecular sexing markers in caenophidian snakes. Two candidate markers were developed with the two primer sets, and successfully amplified by a single band on the agarose gel in male (ZZ) and two bands, differing in fragment sizes, in female (ZW) of 16 caenophidian snakes forCTNNB1and 12 caenophidian snakes forWAC. Another candidate marker was developed with the primer set to amplify the specific sequence forCTNNB1W homolog, and thePCRproducts were successfully obtained in a female‐specific 250‐bpDNAbands. The three candidatePCRsexing markers provide a simple sex identification method based on the amplification of gametologous genes, and they can be used to facilitate effective caenophidian snake conservation and management programs.

The genera Amphiprion and Premnas comprise the common anemonefish that are widely distributed in tropical areas. Species identification of these two genera is difficult due to high, intraspecific, morphological variation. Recently, DNA barcoding has been employed as an efficient tool that uses a short genetic marker in an organism's DNA to enable the identification and recognition of cryptic species. This study applied three regions of mitochondrial DNA—cytochrome c oxidase I (COI), cytochrome b (Cytb) and 16S rRNA—as DNA barcodes for species identification of seven species of Amphiprion and one species of Premnas in Thailand. Three species-delimitation methods—general mixed Yule-coalescent (GMYC), automatic barcoding gap detection (ABGD) and a Bayesian implementation of the Poisson tree processes model (bPTP)—were also used to estimate the number of species. An overlap was found between the intra- and inter-specific genetic divergence values in Cytb and 16S rRNA, but not for the COI data. This indicated that COI was the most effective for identifying different anemonefish species. A three-gene phylogenetic analysis and species-delimitation methods based on both COI and Cytb data suggested cryptic diversity in Amphiprion clarkii, A. percula, A. ocellaris and Premnas biaculeatus. Different distributions were found also for two cryptic species of A. clarkia—one restricted to the Gulf of Thailand and the other to the Andaman Sea. The results confirmed the efficiency of COI as a suitable marker for species identification of anemonefish