Larger Maximum Size Research Articles

A new species of short unpatterned moray eel (Anguilliformes: Muraenidae) from the northwestern Indian Ocean, including the Socotra Archipelago, with a redescription of Gymnothorax pseudoherrei Böhlke

A new species of short brown unpatterned moray eel, Gymnothorax. arabicus sp. nov., is described based on specimens collected from the northwestern Indian Ocean, including the Red Sea, Socotra Archipelago, and Arabian Gulf. The new species is characterized by having the dorsal-fin origin before the gill opening, two branchial pores, one or two median intermaxillary teeth, biserial maxillary teeth, total vertebrae 114–120, and a plain brown head and body with dark yellow color at the tip of the tail. The new species formerly has been confused with G. pseudoherrei but is distinguished from it by having slightly more total vertebrae (114–120 vs. 111–116), dark stripes on the throat and side of the head, and a larger maximum size (ca. 300 mm TL vs. ca. 200 mm TL). Gymnothorax pseudoherrei, currently known from the Maldives and Sri Lanka to the Philippines, Solomon Islands, and northern Australia, is redescribed in the present study. A comparison of the COI mtDNA in BOLD, in association with published phylogenetic evidence, confirms that G. arabicus and G. pseudoherrei form two separate genetic lineages, corroborating the morphological data.

Generation and new infinite families of K2-hypohamiltonian graphs

We present an algorithm which can generate all pairwise non-isomorphic K2-hypohamiltonian graphs, i.e. non-hamiltonian graphs in which the removal of any pair of adjacent vertices yields a hamiltonian graph, of a given order. We introduce new bounding criteria specifically designed for K2-hypohamiltonian graphs, allowing us to improve upon earlier computational results. Specifically, we characterise the orders for which K2-hypohamiltonian graphs exist and improve existing lower bounds on the orders of the smallest planar and the smallest bipartite K2-hypohamiltonian graphs. Furthermore, we describe a new operation for creating K2-hypohamiltonian graphs that preserves planarity under certain conditions and use it to prove the existence of a planar K2-hypohamiltonian graph of order n for every integer n≥134. Additionally, motivated by a theorem of Thomassen on hypohamiltonian graphs, we show the existence K2-hypohamiltonian graphs with large maximum degree and size.

Evaluation of the efficacy of transarterial chemoembolization combined with microwave ablation followed by adjuvant therapy in patients with hepatocellular carcinoma.

This study aimed to explore the efficacy of transarterial chemoembolization (TACE) combined with microwave ablation (MWA) adjuvant to lenvatinib and anti-PD-1 antibodies for patients with hepatocellular carcinoma (HCC). A retrospective analysis of 67 patients with HCC treated at our hospital between October 2018 and May 2022 was conducted. All patients underwent a combination of TACE and MWA. Among them, 29 received postoperative treatment with molecular-targeted agents, like lenvatinib, along with anti-PD-1 antibodies such as sindilizumab, karelizumab, or tirilizumab. The remaining 38 patients did not receive postoperative systemic therapies, like targeted or immunotherapy. The survival and prognosis of all patients were analyzed. Nine patients in the observation group and 29 patients in the control group experienced recurrence, and the median progression-free survival 1 (PFS1) was not reached 'Not Applicable'(NA) and 17.05 months (P=0.035), respectively. Failure to combine adjuvant therapy was identified as an independent risk factor for tumor recurrence, and the observation group had a 0.245 times lower risk of recurrence compared to that in the control group (P=0.005). Multivariable Cox regression analysis confirmed that the maximum tumor size, and tumor number were risk factors for tumor recurrence. Patients with a large maximum tumor size had a 1.519 times higher risk of recurrence compared to those with a small maximum tumor size (P=0.006), and patients with a large number of tumors had a 5.978 times higher risk of recurrence compared to those with a small number of tumors (P=0.02). The median PFS2 of the two groups was 11.795 and 21.257 months, respectively, though not statistically significant (P=0.955). However, there was a disparity in the percentage of BCLC stages associated with recurrence between the two groups. In the observation group approximately 22.22% of patients progressed to stage C, while in the control group, this proportion was 34.48%. The observation group exhibited a lower risk of distant metastasis compared to the control group. Adjuvant treatment of HCC following TACE combined with MWA improved PFS and achieved better clinical outcomes compared to that with TACE combined with MWA alone.

Thermal tolerance for three ornamental tankbuster catfishes

Pet abandonment is an important introduction vector for freshwater aquarium fishes, as unwanted pets become too large for tank dimensions and are released into the environment. Concerns over pet abandonment may be particularly important for the U.S. state of Florida, which exhibits abundant access to freshwater habitats and a climate more favorable to tropical aquarium fishes than other continental U.S. states. Numerous studies have examined the factors affecting establishment for non-native species, including the importance of propagule pressure and climate suitability. For freshwater aquarium species, maximum body size can increase pet abandonment because they grow too large for the tank dimensions (i.e., “tankbusters”). Thus, large maximum body size may increase propagule pressure due to intentional release. In addition to being introduced in sufficient numbers, a match between the thermal tolerance of a species and the thermal habitat is necessary for establishment. Several large-bodied catfishes are found in the aquarium trade, including the goonch Bagarius spp., redtail catfish Phractocephalus hemioliopterus, and tiger sorubim Pseudoplatystoma tigrinum. Here, we experimentally determined the chronic lethal minimum temperature (CLmin) for the three catfishes. CLMin estimates for these three species were higher than many other ornamental species, highest for the redtail catfish (14.3 °C), lower for the tiger sorubim (11.0 °C), and lowest (9.9 °C) for the goonch. Given these lethal temperatures, the distribution of redtail catfish would be limited to South Florida while the tiger sorubim and goonch could live, provided other habitat characteristics are suitable, up to ~28°N Latitude in Florida.

Long-term effects of incubation temperature on growth and thermal physiology in a small ectotherm.

Thermal conditions in the developmental environment can substantially affect an individual's phenotype, particularly in egg-laying ectotherms. However, whether these effects persist into adulthood is rarely examined. To investigate this, we incubated delicate skink, Lampropholis delicata, eggs at either cool (22°C), mild (26°C) or hot (30°C) temperatures. After hatching, we measured growth, thermal performance curves of locomotor activity, and thermal sensitivity of resting metabolic rate of offspring as juveniles (4-6 weeks of age), sub-adults (approx. 200 days of age), and adults (approx. 2 years of age), and then measured developmental temperature impacts on male fertility. Incubation temperature had a lasting effect on growth and locomotor performance, with cool and hot incubation temperatures resulting in faster growth and larger maximum size, and hot incubation temperatures reducing locomotor performance at all timepoints. Effects on resting metabolic rate were only present in sub-adults, with a higher metabolic rate at high and average body mass and negative metabolic scaling exponent in cool-incubated lizards. Additionally, cool and hot incubation treatments resulted in shorter sperm midpieces and heads. Incubation temperature did not affect testis mass or sperm count. Overall, our results demonstrate that incubation temperature can have lasting effects on later life stages, highlighting the importance of maternal nest-site selection, but that some effects are age dependent. This article is part of the theme issue 'The evolutionary ecology of nests: a cross-taxon approach'.

Age, Growth, Maturation and Mortality of Picarel Spicara flexuosa (Sparidae) from the Crimea Water Area (Black Sea)

The results of the study of the sex and size-age structure, growth, maturation, sexual inversion, dynamics of the gonadosomatic index and mortality of 1948 individuals of the picarel Spicara flexuosa caught in the Crimea water area in 2020–2021 are presented. The total sex ratio in catches is biased towards females (3.5 : 1.0); sex inversion was recorded in 50% of females with a total body length of 13.5 ± 0.05 cm at the age of 3+. The maximum length of females is 15.1 cm, males, 22.0 cm; the weight is 29.0 and 132.2 g, respectively. The maximum age of females and males is 4 and 7 years, respectively. The values of the parameters of the von Bertalanffy equation are calculated: for females, the asymptotic length is 15.69 cm, the asymptotic weight is 32.0 g, the growth coefficient is 0.49 year–1; for males, 18.32 cm, 59.7 g and 0.44 year–1, respectively. A value of the exponent in the length-weight relationship is 2.68 for females (negative allometry) and 3.0 for males (isometry). The sexual maturity of 50% of females occurs at a length of 10.34 ± 0.21 cm at the age of 1+. The peak of spawning occurs in June. The rates of total, natural and fishing mortality are 1.2, 1.9 and 0.3 year–1, respectively in both sexes; the exploitation rate is 0.25, which indicates a low fishing pressure. It is established that S. flexuosa from northern populations is characterized by larger maximum sizes, a higher growth rate and a longer life expectancy

The Dynamics of Maximum Lengths for the Invasive Silver-Cheeked Toadfish (Lagocephalus sceleratus) in the Eastern Mediterranean Sea

The Eastern Mediterranean Sea is the most invaded sea on the planet, with 666 non-indigenous species now recorded in the region. However, not all of these become successful in their new environments. Success here is defined by wide geographical spread, increased abundances, and larger maximum sizes than their native range. The silver-cheeked toadfish Lagocephalus sceleratus (Gmelin 1789) was first recorded in the Mediterranean Sea in 2003. It has now spread to all corners of the basin and is increasingly abundant in the Eastern Mediterranean Sea where it reaches monstrous sizes compared to the maximum sizes reported from its native range. This contribution presents three well-documented new weight records from the Dodecanese Islands, Greece: one specimen weighing 8.5 kg from 2012, and two specimens weighing 8 and 9 kg, respectively, from 2021. The latter is also confirmed with other well-documented larger-size records, along with a physiological hypothesis suggesting how such large sizes are reached.

Socio-ecological correlates of neophobia in corvids

Behavioral responses to novelty, including fear and subsequent avoidance of novel stimuli, i.e., neophobia, determine how animals interact with their environment. Neophobia aids in navigating risk and impacts on adaptability and survival. There is variation within and between individuals and species; however, lack of large-scale, comparative studies critically limits investigation of the socio-ecological drivers of neophobia. In this study, we tested responses to novel objects and food (alongside familiar food) versus a baseline (familiar food alone) in 10 corvid species (241 subjects) across 10 labs worldwide. There were species differences in the latency to touch familiar food in the novel object and novel food conditions relative to the baseline. Four of seven socio-ecological factors influenced object neophobia: (1) use of urban habitat (versus not), (2) territorial pair versus family group sociality, (3) large versus small maximum flock size, and (4) moderate versus specialized caching (whereas range, hunting live animals, and genus did not), while only maximum flock size influenced food neophobia. We found that, overall, individuals were temporally and contextually repeatable (i.e., consistent) in their novelty responses in all conditions, indicating neophobia is a stable behavioral trait. With this study, we have established a network of corvid researchers, demonstrating potential for further collaboration to explore the evolution of cognition in corvids and other bird species. These novel findings enable us, for the first time in corvids, to identify the socio-ecological correlates of neophobia and grant insight into specific elements that drive higher neophobic responses in this avian family group. VIDEO ABSTRACT.

Age and growth of grey triggerfish Balistes capriscus from trans-Atlantic populations.

Anthropogenic factors that negatively impact reef fishes can include changes in life-history patterns of fisheries-targeted species. Understanding these impacts on growth and population age structure is essential in the management of exploited populations of fishes. This is the first study to directly compare age and growth for a major fisheries species between east and west populations of a transatlantic reef fish. The main goal of this study was to document age and growth in grey triggerfish Balistes capriscus from coastal waters of Ghana in the Gulf of Guinea (GOG) and compare those with the previous growth studies from that region and with the western Atlantic population. A secondary objective of this study was to evaluate the use of otoliths to age triggerfish and to provide a preliminary comparison with spine-derived age estimates. The results obtained from this study provided an updated understanding of the growth and age structure of the eastern B. capriscus population in GOG. The authors documented that shifts in population attributes occurred for B. capriscus after its major decline in abundance. The differences in physical and biotic characteristics of the East and West Atlantic regions and the differences in collection methods of samples make direct comparisons of growth parameters difficult. Nonetheless, overall differences in maximum sizes and ages were apparent; the western Atlantic population had a larger maximum size and older maximum age. The authors also documented that sagittal otoliths can be used to provide age estimates for triggerfish species, and otoliths as an ageing structure had better between-reader precision compared to dorsal spines.

Planet-induced Vortices with Dust Coagulation in Protoplanetary Disks

Abstract In this work, we study how the dust coagulation/fragmentation will influence the evolution and observational appearances of vortices induced by a massive planet embedded in a low-viscosity disk by performing global 2D high-resolution hydrodynamical simulations. Within the vortex, due to its higher gas surface density and steeper pressure gradients, dust coagulation, fragmentation, and drift (to the vortex center) are all quite efficient, producing dust particles ranging from 1 μm to ∼1.0 cm, as well as an overall high dust-to-gas ratio (above unity). In addition, the dust size distribution is quite nonuniform inside the vortex, with the mass-weighted average dust size at the vortex center (∼4.0 mm) being a factor of ∼10 larger than other vortex regions. Both large (∼millimeter) and small (tens of microns) particles contribute strongly to affect the gas motion within the vortex. As such, we find that the inclusion of dust coagulation has a significant impact on the vortex lifetime and the typical vortex lifetime is about 1000 orbits. After the initial gaseous vortex is destroyed, the dust spreads into a ring with a few remaining smaller gaseous vortices with a high dust concentration and a large maximum size (∼millimeter). At late time, the synthetic dust continuum images for the coagulation case show as a ring inlaid with several hot spots at the 1.33 mm band, while only distinct hot spots remain at 7.0 mm.

Palaeoplex gen. nov. and Lufubuchromis gen. non, two new monotypic cichlid genera (Teleostei: Cichlidae) from northern Zambia.

Two monotypic haplochromine cichlid genera (Teleostei: Cichlidae) of the Pseudocrenilabrus group are described from northern Zambia. One new genus is Palaeoplex gen. nov., with Pa. palimpsest sp. nov. as the type species, from the Luongo and Kalungwishi Rivers (Upper Congo drainage, Luapula subdrainage). It is diagnosed by a unique combination of morphological characters: (1) a fully developed infraorbital series without a distinct gap between the lachrymal and second infraorbital bone, (2) fused hypuralia 1+2 and hypuralia 3+4, (3) molariform teeth on the sagittal series of the lower pharyngeal jaw, and (4) a large maximum size. The second new genus, Lufubuchromis gen. nov., with L. relictus sp. nov. as the type species, is restricted to the upper Lufubu River catchment (Upper Congo drainage, Lake Tanganyika subdrainage). It is diagnosed by a unique combination of morphological characters: (1) a fully developed infraorbital series without a distinct gap between the lachrymal and second infraorbital bone, (2) fused hypuralia 1+2 (rarely with a visible suture) and fused hypuralia 3+4, (3) a unique male coloration pattern, i.e. deep crimson red colored areas on the anterior ventral flank parts, chest and belly and on the lower head; remaining parts of flanks and caudal peduncle bluish), and (4) a Pseudocrenilabrus blotch present in both sexes. Both new genera are compared with all remaining taxa of the Pseudocrenilabrus group and with all representatives of all other major haplotilapiine lineages.

Efficiency of endovascular embolization and predictors of postoperative complications in patients with different types of brain arteriovenous malformations

Aim. (1) To evaluate the efficiency of endovascular embolization of brain arteriovenous malformations (AVMs) with seizure or hemorrhage in relation to radicalness and postoperative complication development and (2) to determine the predictors of postoperative complications after endovascular embolization of AVMs. Methods. In this retrospective study, we examined the treatment of 192 patients with brain AVMs with seizure (seizure group; n = 85) or hemorrhage (hemorrhage group; n = 107). All the patients underwent total endovascular embolization of the malformations, and the follow-up period was 12 months. The two different patient groups were identified, and the predictors of the development of adverse events (hemorrhagic and ischemic complications) in the early postoperative period (hospital stay) were determined. Results. Twelve months after control cerebral angiography was performed, recanalization was observed in 7 (8.2%) and 14 (13.1%) patients in the seizure and hemorrhage groups, respectively (p = 0.432). The frequency of complications was 20% and 29.9% in the seizure and hemorrhage groups, respectively (p = 0.162). The mortality rate during hospitalization was 0% and 9.3% in the seizure and hemorrhage groups, respectively (p = 0.026). Multivariate regression analysis revealed that a history of hemorrhage, the location of AVMs in functionally significant zones, and a large maximum size of AVMs are predictors of the development of postoperative complications. Conclusion. Endovascular embolization is an effective, minimally invasive approach for the treatment of different types of brain AVMs. Considering the natural risks of brain AVMs according to the literature, endovascular embolization is associated with a low frequency of early postoperative complications. Received 14 February 2019. Revised 24 May 2019. Accepted 28 May 2019. Funding: The study did not have sponsorship. Conflict of interest: Authors declare no conflict of interest.

Differentiation Between Lymphangioleiomyomatosis and Birt-Hogg-Dubé Syndrome: Analysis of Pulmonary Cysts on CT Images.

The purposes of this study were to identify diagnostic imaging markers for differentiating pulmonary cysts in lymphangioleiomyomatosis and Birt-Hogg-Dubé syndrome and to identify potential risk factors for spontaneous pneumothorax in the two diseases. This retrospective study included 44 patients with lymphangioleiomyomatosis (44 women; mean age, 35 ± 10.9 years) and 13 patients with Birt-Hogg-Dubé syndrome (nine men, four women; mean age, 45.1 ± 10.9 years). CT findings were analyzed to determine the shape; presence of septation, wall visibility, and subpleural cysts; size; number; distribution; location of the largest cyst; and presence of cysts encircling the bronchovascular bundle ("air-cuff" sign) and of mediastinal fat indentation. Multiple logistic regression was performed to identify risk factors for spontaneous pneumothorax. Compared with patients with lymphangioleiomyomatosis, patients with Birt-Hogg-Dubé syndrome were significantly older, and more of them were men. The cysts in these patients had a more irregular shape, more septation, lower and more peripheral distribution, larger maximum size, and more attachment to the pleura, air-cuff sign, indentation on mediastinal fat, and subpleural cysts larger than 2 cm. The maximum diameter of cysts was the sole independent risk factor for spontaneous pneumothorax (p = 0.027; 95% CI, 1.043-1.992) in both diseases. ROC analysis showed an AUC of 0.745 (95% CI, 0.612-0.851), and the optimal cutoff value was 22 mm (sensitivity, 72.5%; specificity, 76.5%). Several CT imaging markers may help in differentiating pulmonary cysts in patients with lymphangioleiomyomatosis and those with Birt-Hogg-Dubé syndrome and in predicting spontaneous pneumothorax.

Resident species with larger size metrics do not recruit more offspring from the soil seed bank in old‐field meadow vegetation

Abstract According to the traditional “Size Advantage” (SA) hypothesis, plant species with larger body size are expected to be more successful when competition is intense, that is, within severely crowded vegetation. Recent studies in old‐field habitats, however, have shown that those species with greater numerical abundance as resident plants generally have a relatively small minimum reproductive threshold size (MIN), not a relatively large maximum potential body size (MAX). In this study, we test for a size advantage in terms of species abundance representation in the soil seed bank, and we extend the SA hypothesis to include two additional size metrics: leaf size and seed size. Specifically, we ask, for resident species within a crowded old‐field meadow: is larger seed size, leaf size, and/or body size associated with greater reproductive / recruitment success (i.e. number of germinable seeds within—and establishing plants emerging from—the soil seed bank)? We collected soil cores for a greenhouse experiment to record relative species abundances of germinable seeds in the seed bank, and we used a field experiment to record local abundances of species emerging from the resident seed bank within denuded plant neighbourhoods over three subsequent field seasons. We found no general support for the SA hypothesis involving any of the size metrics, and none of the latter was a strong predictor of the number of germinable seeds emerging from soil cores in the greenhouse experiment. However, for species establishing in the field experiment from the seed bank over the 3‐year survey period, more abundant species in years 2 and 3 tended to be those with smaller MIN, and thus smaller MAX. In addition, within more crowded neighbourhoods, representation of reproductive plants was generally greater for species with relatively small MIN (and hence small MAX). Synthesis. Our results extend the support for the “Reproductive Economy Advantage” hypothesis in old‐field habitats, to include not just established, largely undisturbed vegetation, but also very early stages of recruitment from seed within locally crowded plant neighbourhoods. Specifically, more successful species here are not those with relatively large potential body size (MAX); they are species capable of producing at least some offspring despite severe body size suppression, because they have a relatively small MIN. We summarize our interpretation using a simple conceptual model for predicting selection effects of local neighbourhood crowding on variation in fecundity (fitness estimate) of resident plants, resulting from genetic covariation in MAX and MIN. Relatively large potential body size (MAX) should be expected to promote fitness here, not when competition from near neighbour effects is severe, but when its effects are locally more moderate, or virtually absent—and hence relatively rarely within the generally crowded vegetation of old‐field habitats.

Life history traits of a poorly known pelagic fish, Aethotaxis mitopteryx (Perciformes, Notothenioidei) from the Weddell Sea

Amongst the nototheniid subfamily Pleuragramminae, Aethotaxis mitopteryx is an infrequently collected high Antarctic species with an array of morphological and physiological adaptations supporting an evolutionarily derived benthopelagic lifestyle. The present study deals with some poorly known life history traits of this species, counting on 79 specimens collected in the Weddell Sea during 2014 and 2015 austral summer. Annulation pattern in sagittal otoliths were used to assess population age structure and growth rate, while macroscopic and histological analyses of gonads were performed to estimate reproductive status and features of gametogenesis. The sex ratio of the sampled population was close to parity, with females significantly larger than males. Based on the von Bertalanffy growth model, females attained a larger maximum size (40 vs. 27 cm) at a lower rate (0.05 vs. 0.12 years−1) than males. Individual longevity was remarkable in both sexes, females and males attaining 62 and 32 years of age, respectively. Females showed group synchronous oocyte development and presumed high reproductive effort, as indicated by the large size of residual hydrated oocytes in regressing individuals (4.6–4.8 mm). Body sizes at sexual maturity were 33 and 19 cm in females and males, corresponding to 32 and 11 years of age, respectively. All specimens were caught far from the reproductive season. From an evolutionary perspective, it appears that the process of pelagization similarly influenced the life strategies of the species within the clade Pleuragramminae, which shared high reproductive effort linked to early sexual maturity, slow somatic growth and long life span.

Contributory Factors to Hemorrhage After Ultrasound-Guided Fine Needle Aspiration of Thyroid Nodules with an Emphasis on Patients Taking Antithrombotic or Anticoagulant Medications

Background: Thyroid nodules are a common clinical problem and ultrasound-guided fine needle aspiration (US-FNA) biopsy is widely used for evaluation of thyroid nodules. However, few studies have addressed the contributing factors to hemorrhage after US-FNA of thyroid nodules. Objectives: To assess the contributory factors related to patient characteristics, ultrasound (US) features of the thyroid nodules, and the US-FNA procedures to affect hemorrhage complications after US-FNA of thyroid nodules. Patients and Methods: Between March 2014 and April 2015, 366 consecutive patients who underwent US-FNA of thyroid nodules were enrolled in this retrospective study. The characteristics of hematomas, including the location, maximum size, and clinical course, were assessed. The relationships between hematomas and factors related to the medical characteristics of patients, US characteristics of the nodules, and FNA procedural factors were analyzed. Results: Data on 365 nodules in 321 patients who underwent US-FNA of thyroid nodules were analyzed. Minor hemorrhagic complications developed in 14 (3.8%) of the 365 nodules. There were no statistically significant differences between patients taking or not taking an anticoagulant or antithrombotic (P = 0.270). Factors related to increased risk of hematoma were male sex (P = 0.031), larger maximum size (P = 0.002), a cystic or predominantly cystic nodule (P < 0.0001), a probable benign nodule (P < 0.0001), thicker needle size (P < 0.0001), and a greater number of the needle passes (P = 0.005). Conclusion: US-FNA can be performed safely even in patients taking anticoagulant or antithrombotic agents. Factors related to hemorrhagic complications are male sex, larger nodules, cystic or predominantly cystic nodules, probably benign nodules, thicker needles and a greater number of needle passes.

Gray Triggerfish Reproductive Biology, Age, and Growth off the Atlantic Coast of the Southeastern USA

AbstractThe Gray Triggerfish Balistes capriscus supports fisheries on both sides of the Atlantic Ocean. We utilized fishery‐independent samples to assess the age structure, growth, sex ratio, size and age at maturity, spawning season, and spawning frequency of the Gray Triggerfish population off the southeastern U.S. Atlantic coast. From 1991 to 2012, 7,685 samples were collected, ranging in FL from 82 to 578 mm and ranging in age from 0 to 13 years. Our study provides key life history information for an exploited population and is the first to comprehensively describe age, growth, and reproduction for a Balistes species. We documented that the Gray Triggerfish is sexually dimorphic, with adult males attaining larger sizes at age and a larger maximum size than females. Sex‐specific growth curves were fitted, yielding the following von Bertalanffy equations: FLt = 419[1 – e–0.54(t + 0.61)] for males and FLt = 352[1 – e–0.94(t + 0.22)] for females. This species is characterized by a medium size at maturity (the smallest mature female was 179 mm FL; the smallest mature male was 183 mm FL) and relatively early age at maturity (the youngest mature female and male were age 0). Some shifts in population attributes coincided with a period of increased fishing pressure. Due to tighter regulations on snapper and grouper fisheries, the Gray Triggerfish has become a more targeted species. Fisheries biologists and managers should continue to evaluate potential impacts and establish management regulations that consider the region‐specific reproductive season, size and age at maturity, and sex‐specific differences in growth documented in this study.Received April 20, 2016; accepted January 9, 2017 Published online March 30, 2017

Growth of freshwater Etheria elliptica oyster (Lamarck, 1807) reared in cages in the Pendjari River (Benin, West Africa)

In this paper, we assess the growth performance, survival rate and abiotic factors affecting Etheria elliptica (Mollusca: Bivalvia: Etheriidae), the African freshwater oyster, a species that is widespread in tropical Africa where it is widely harvested for food and as a commodity. We collected wild oysters from the Pendjari River (Benin) and grouped them into small (23.4 ± 5.2 mm) and large (55.8 ± 7.7 mm) size classes. They were reared in cages in the Pendjari River from January to December 2009. Shell height was measured on a monthly basis, and estimated growth parameters were assessed using the von Bertalanffy growth function. Overall, the growth parameter estimates for pooled size classes were K = 0.0718 month−1 and L∞ = 82.2 mm. We estimated the time to reach minimum commercial size T 65mm (female sexual maturity size) to be 22 months (1.8 years). Small oysters exhibited a peak in growth rate (2.775 mm month−1 ) in May, whereas large-sized oysters grew fastest (1.707–2.781 mm month−1 ) in August–September during the rainy/flood season. Survival of small-sized oysters declined sharply from May (60%) to June (11%) at the onset of the rainy season, six months after the beginning of experiment, while large oysters had higher survival in June (79.2%), which decreased in December (26.4%). Among abiotic factors investigated, water transparency was negatively correlated with the growth increment of small-sized oysters (p is a suitable candidate for culture due to its large maximum size, reasonable growth rate, and wide geographic range.

Perisesarma tuerkayi, a new species of mangrove crab from Vietnam (Decapoda, Brachyura, Sesarmidae), with an assessment of its phylogenetic relationships

A new species of Perisesarma, P. tuerkayi, is described from mangroves of Tan Thoi Island, southern Vietnam. Morphologically, the new species differs most significantly from congeners by the tuberculation pattern of the chelar dactylus, its unique G1 morphology, an unusually large maximum body size, and relatively short and broad ambulatory legs. Genetically, P. tuerkayi n. sp. is markedly divergent from other congeneric species, both in mitochondrial and nuclear DNA. It is the fifth species of Perisesarma reported from Vietnam.

A new deepwater legskate, Sinobatis kotlyari n. sp. (Rajiformes, Anacanthobatidae) from the southeastern Indian Ocean on Broken Ridge.

Sinobatis kotlyari n. sp. is described, based on the nearly adult 331 mm TL holotype male from 1400 m depth in the southeastern Indian Ocean at Broken Ridge. The new species is assigned to Sinobatis due to mainly characters of its clasper and cranium fontanelle distinguishing it from congeners and other anacanthobatid skates with clasper features known. It further differs from its morphologically closest congener, S. borneensis, which is only known from the northwestern Pacific Ocean, e.g. in larger maturing size, longer snout and head, the absence of a snout filament and skin fold on tail, a longer caudal fin, and in colouration. The two congeners known from the eastern Indian Ocean, S. bulbicauda and S. cae-rulea, mature at much larger size, grow to larger maximum size and differ in numerous morphometric and meristic characters, as well as in colouration. The type locality appears to be very remote as compared with other Indian Ocean legskates, which have primarily been found on continental and insular slopes.