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The vital parameter data for 62 stocks, covering 38 species, collected from the literature, including parameters of age, growth, and reproduction, were log-transformed and analyzed using multivariate analyses. Three groups were identified and empirical equations were developed for each to describe the relationships between the predicted finite rates of population increase (λ') and the vital parameters, maximum age (Tmax), age at maturity (Tm), annual fecundity (f/Rc)), size at birth (Lb), size at maturity (Lm), and asymptotic length (L∞). Group (1) included species with slow growth rates (0.034 yr(-1) < k < 0.103 yr(-1)) and extended longevity (26 yr < Tmax < 81 yr), e.g., shortfin mako Isurus oxyrinchus, dusky shark Carcharhinus obscurus, etc.; Group (2) included species with fast growth rates (0.103 yr(-1) < k < 0.358 yr(-1)) and short longevity (9 yr < Tmax < 26 yr), e.g., starspotted smoothhound Mustelus manazo, gray smoothhound M. californicus, etc.; Group (3) included late maturing species (Lm/L∞ ≧ 0.75) with moderate longevity (Tmax < 29 yr), e.g., pelagic thresher Alopias pelagicus, sevengill shark Notorynchus cepedianus. The empirical equation for all data pooled was also developed. The λ' values estimated by these empirical equations showed good agreement with those calculated using conventional demographic analysis. The predictability was further validated by an independent data set of three species. The empirical equations developed in this study not only reduce the uncertainties in estimation but also account for the difference in life history among groups. This method therefore provides an efficient and effective approach to the implementation of precautionary shark management measures.

A major difficulty in managing wildlife trade is the reliance on trade data (rather than capture data) to monitor exploitation of wild populations. Collected organisms that die or are rejected before a point of sale often go unreported. For the global marine aquarium trade, identifying the loss of collected fish from rejection, prior to export, is a first step in assessing true collection levels. This study takes a detailed look at fish rejections by buyers before export using the Papua New Guinea marine aquarium fishery as a case study. Utilizing collection invoices detailing the species and quantity of fish (Actinopteri and Elasmobranchii) accepted or rejected by the exporting company it was determined that, over a six month period, 24.2% of the total fish catch reported (n = 13,886) was rejected. Of the ten most collected fish families, rejection frequency was highest for the Apogonidae (54.2%), Chaetodontidae (26.3%), and Acanthuridae (18.2%) and lowest for Labridae (6.6%) and Hemiscylliidae (0.7%). The most frequently cited reasons for rejection were fin damage (45.6% of cases), undersized fish (21.8%), and fish deemed too thin (11.1%). Despite fishers receiving feedback on invoices explaining rejections, there was no improvement in rejection frequencies over time (r = -0.33, P = 0.15) with weekly rejection frequencies being highly inconsistent (range: 2.8% to 79.4%; s = 16.3%). These findings suggest that export/import statistics can greatly underestimate collection for the marine aquarium trade as additional factors such as fisher discards, escapees, post-collection mortalities, and unregulated domestic trade would further contribute to this disparity.

We present the complete mitochondrial genome of the Epaulette Shark Hemiscyllium ocellatum, sequenced with 24 primer sets. The 16,728 bp long circular genome consisted of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and a non-coding control region. Several protein-coding genes ended with incomplete stop codons (TA- or T-). Phylogenetic analysis indicated that H. ocellatum clusters within the Hemiscylliidae clade but separately from members of its sister genus Chiloscyllium. Utilization of the genome and primer sets presented here will be beneficial to future molecular studies involving H. ocellatum and other members of the Orectolobiformes.

The complete mitochondrial genome of the grey bamboo shark, Chiloscyllium griseum (Orectolobiformes: Hemiscylliidae) was obtained, with a total of 16 755 base pairs (bp). The mitogenome encoded 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs and a noncoding control region, a gene arrangement identical to the most common type found in vertebrates. All tRNA sequences were folded into typical cloverleaf secondary structure with the exception of tRNA-Ser2, in which the DHU arm stem was replaced with 12 unpaired nucleotides and formed a simple loop. In the control region, the putative termination-associated sequences (TAS) with hairpin-loop structure and the conserved sequence blocks (CSB) I-III were identified and considered to be associated with the replication and transcription of mtDNA. No repeat motifs were found in the mitogenome of C. griseum . On the basis of the mitogenomic data available in the Class Chondrichthyes from both Genbank and this study, and the phylogenetic analyses using maximum likelihood (ML) and Bayesian inference (BI) methods, the results strongly support the basal division between batoids and sharks and the monophyly of the Superorder Galeomorphii, and confirm the phylogenetic position of C. griseum in the Subclass Elasmobranchii. This study suggests that the mitogenomic data are more robust for reconstructing phylogenetic relationships than individual genes in the Elasmobranchii.

A new record of Hasselt’s bamboo shark Chiloscyllium hasseltii (Orectolobiformes: Hemiscylliidae) has been confirmed from the St. Martin’s Island, the northeastern part of the Bay of Bengal of Bangladesh. Two male specimens were collected on 19th December 2018 from the coast of St. Martin’s Island as a bycatch of the local fishermen. The traditional morphometric method was applied for taxonomic identification which was further validated by a molecular approach based on partial cytochrome c oxidase subunit I (COI) sequences (DNA barcodes). The key characteristics of this species are the distance from first to second dorsal fin less than 9.3% of TL; first dorsal fin height less than 6.6% of TL and second dorsal fin height less than 5.8% of TL. The morphometric, meristic and DNA barcoding data thus confirmed the presence of C. hasseltii in Bangladesh. With this report a new shark species has been added in the treasure of the marine ichthyofaunal diversity of Bangladesh and also updates the geographical distribution range of this species.

Using a combination of stable isotope analyses (SIA), fatty acid profiling (FAP), and FA-specific SIA, we investigated the relative importance of terrestrial- and marine-derived carbon, and spatial (inshore vs. offshore), seasonal (wet vs. dry season), and ontogenetic variations, in the relative contribution of detrital pathways to the white-spotted bamboo shark, Chiloscyllium plagiosum in the Pearl River estuary. SIA and FAP suggested the sharks acquired carbon from both marine- and terrestrial-derived detritus via consumption of polychaetes and small crustaceans, with carbon from terrestrial sources being more important to juveniles (25–50 cm long) at inshore locations. Juveniles generally had significantly higher levels of diatom FA, bacterial FA, and long-chaincarbon– saturated FA biomarkers than adults (> 65 cm), especially during the wet season, suggesting that they relied on primary consumers which assimilated a mixture of autotrophic and detrital carbon sources. Levels of zooplankton and animal-derived FA biomarkers generally increased with shark size, indicating an ontogenetic dietary shift. Utilizing the results of FA-specific SIA (i.e., δ13C values of individual bacterial FA of detritus) from four sources (i.e., terrestrial plant litter, macroalgae, phytoplankton, and sediments), Bayesian mixing models revealed juveniles in the inner estuary assimilated significantly higher amounts of terrestrial carbon (37–45%) than adults (22–37%) or sharks in the outer estuary (1–36%). The combined use of multiple dietary tracers effectively revealed the interaction of various detrital pathways to marine predators in the Pearl River estuary, and highlighted the importance of terrestrial–marine linkages for interpretation of energy flow in coastal ecosystems.

We report the first geographical record of the Burmese bamboo shark, Chiloscyllium burmensis (Orectolobiformes: Hemiscylliidae) from the coast of Bay of Bengal, Bangladesh. Three specimens (two males and one female) of C. burmensis were collected on 22nd March 2018, from the Bangladesh Fisheries Development Corporation Fish Landing Center of Cox’s Bazar. Morphometric and molecular approach were applied for taxonomic identification. The shark showed a body slender, snout blunt, nostrils subterminal and well separated from snout tip. Mouth slightly closer to eyes than snout tip, labial folds connected across chin by a dermal fold. Pectoral and pelvic fins are relatively thin. The key characteristics of this species are small eyes, less than 1.25% of total length (TL); distance from vent to tail tip more than 67% of TL; head length less than 15.8% of TL; distance from nose tip to vent less than 31% of TL. The morphometric and DNA barcoding data confirmed the presence of C. burmensis in Bangladesh. This report updates the geographical distribution for this species confirming its presence in the coastal region of Bangladesh.

Yorkeria chonburiensis n. sp. (Tetraphyllidea: Onchobothriidae) is described from the spiral intestine of a specimen of the brownbanded bamboo shark, Chiloscyllium punctatum, collected from the Gulf of Thailand, Chon Buri Province, Thailand. Yorkeria chonburiensis n. sp. is distinguished from all other species of Yorkeria by the pattern of proglottids (craspedote as opposed to acraspedote) and the proglottid number (more than 168). The new species is larger than all other members of Yorkeria, and the medial hooks are slightly larger than the lateral hooks with a ratio of 1:1.87–1:1.96. The position of the genital pore is 29–34% from the anterior margin of proglottid, greater than all other members of Yorkeria.

A new genus of trypanorhynch cestodes is described from the brownbanded bambooshark, Chiloscyllium punctatum Mueller & Henle (Hemiscylliidae) from off Nickol Bay, Western Australia. Poecilorhynchus perplexus n. g., n. sp. is placed in the Eutetrarhynchidae Guiart, 1927 because it is characterised by an elongate, acraspedote scolex with two oval bothria, the absence of bothrial pits, elongate bulbs, the presence of gland-cells within the bulbs and prebulbar organs, retractor muscles inserting at the base of each bulb and an acraspedote strobila. It can be distinguished from all other genera in this family by its possession of a poeciloacanthous typical armature, with a chainette composed of two longitudinal files of uncinate hooks on the external tentacular surface.

Two new species of the tapeworm genus Yorkeria are described from the spiral intestine of a specimen of the Brownbanded bambooshark, Chiloscyllium punctatum, collected from a fish market in Bangsarai, Thailand in 1996. The larger of the 2 new tapeworm species, Y. hilli, possesses fewer proglottids, fewer testes, and is smaller than most of its congeners. The smaller of the 2 new species, Y. kelleyae, conspicuously differs from all of its congeners in its possession of medial hooks that are only slightly larger than the lateral hooks (rather than conspicuously larger). Scanning electron microscopy shows both species to possess elongate filitriches on their distal prehook locular surfaces and elongate filitrichs and spinitrichs on their proximal bothridial, distal posthook locular surfaces, pedicels, and cephalic peduncles. In both species, the spinitrichs on the proximal bothridial surfaces, pedicels, and peduncles are very large and readily visible with light microscopy. Whereas the spinitrichs on these 4 surfaces are bluntly rounded in Y. hilli, they are pointed in Y. kelleyae. Examination of specimens identified as Y. parva, collected by several previous workers from a diversity of hosts and localities, calls into question the conspecificity of at least some of this material. The unusual scolex form suggests that the configuration of the cerebral ganglionic mass in species of Yorkeria may differ from that seen in most other tetraphyllidean taxa.