Search

We recorded the morphological characteristics and effect of preservation methods on the structure of the egg veils of Lophius litulon found in field investigations. The egg veils were characterized as translucent sheet‐shape with parallel opaque creases spaced approximately 2 cm apart. The egg veils were found to be composed of pentagonal or hexagonal chambers with rounded corners arranged in one layer, and each chamber enveloped one to three embryos. Cryopreservation is recommended to prevent structural changes in the egg veil rather than ethanol solution and neutral buffered formalin solution. [ABSTRACT FROM AUTHOR]

Thought to be monotypic for decades, the only species in the goosefish genus Lophiomus Gill, Lm. setigerus (Vahl), shows a wide range of morphological variation and is distributed widely in the Indo-West Pacific (IWP). In this study, datasets for two mitochondrial and two nuclear genes sequences obtained from samples of Lophiomus collected in different localities across the IWP were constructed and analyzed to explore the phylogeny and species diversity within the genus. Our integrated approach with multiline evidence unveiled an unanticipated richness of at least six delimited species of Lophiomus. Herein, based on materials already available from museums and new specimens obtained primarily through the Tropical Deep-Sea Benthos program surveying IWP benthic fauna, we formally describe three new species: Lm. immaculioralis sp. nov., Lm. nigriventris sp. nov., and Lm. carusoi sp. nov. Also, we resurrect Lm. laticeps stat. rev. from synonyms of Lm. setigerus. These species can be diagnosed by genetics, body coloration, patterns on the floor of the mouth, peritoneum pigmentation, morphometric measurements, and meristic counts of cranial spines, dorsal-fin spines, and pectoral-fin and pelvic-fin rays from each other and from Lm. setigerus. The species Lm. setigerus, as well as the genus Lophiomus, are re-described accordingly based on the new results. Amended identification keys to the four extant lophiid genera and to species of Lophiomus are also provided.

Abstract Background The anglerfish, belonging to the teleost order Lophiiformes, are a diverse and species-rich group of fish that are known to exhibit a number of unique morphological, reproductive and immunological adaptations. Work to date has identified the loss of specific adaptive immune components in two of the five Lophiiformes sub-orders (Lophioidei and Ceratioidei), while no anomalies have been identified to date in two other sub-orders, Antennaroidei and Chaunacoidei. The immunogenome of the fifth sub-order, Ogcocephaloidei has not yet been investigated, and we have therefore used whole genome shotgun sequencing, combined with RNA-seq, to survey the adaptive immune capabilities of the polka-dot batfish, O. cubifrons, as a representative of this as yet unexplored sub-order. Results We find that the O. cubifrons genome encodes the core genes needed to mount adaptive T and B cell responses. These genes include those necessary for rearranging and editing antigen receptors, the antigen receptors themselves; as well as the co-receptors, signalling molecules, and antigen presenting molecules (both class I and class II) needed for B cell and T cell development and activation. Conclusions From an immune perspective, the polka-dot batfish has a canonical complement of adaptive immune genes, and does not exhibit any of the adaptive immune changes previously identified in monkfish and oceanic anglerfish.

Background: The anglerfish, belonging to the teleost order Lophiiformes, are a diverse and species-rich group of fish that are known to exhibit a number of unique morphological, reproductive and immunological adaptations. Work to date has identified the loss of specific adaptive immune components in two of the five Lophiiformes sub-orders (Lophioidei and Ceratioidei), while no anomalies have been identified to date in two other sub-orders, Antennaroidei and Chaunacoidei. The immunogenome of the fifth sub-order, Ogcocephaloidei has not yet been investigated, and we have therefore used whole genome shotgun sequencing, combined with RNA-seq, to survey the adaptive immune capabilities of the polka-dot batfish, O. cubifrons, as a representative of this as yet unexplored sub-order. Results: We find that the O. cubifrons genome encodes the core genes needed to mount adaptive T and B cell responses. These genes include those necessary for rearranging and editing antigen receptors, the antigen receptors themselves; as well as the co-receptors, signalling molecules, and antigen presenting molecules (both class I and class II) needed for B cell and T cell development and activation. Conclusions: From an immune perspective, the polka-dot batfish has a canonical complement of adaptive immune genes, and does not exhibit any of the adaptive immune changes previously identified in monkfish and oceanic anglerfish. [ABSTRACT FROM AUTHOR]

Major ecological transitions are thought to fuel diversification, but whether they are contingent on the evolution of certain traits called key innovations 1 is unclear. Key innovations are routinely invoked to explain how lineages rapidly exploit new ecological opportunities. 1,2,3 However, investigations of key innovations often focus on single traits rather than considering trait combinations that collectively produce effects of interest. 4 Here, we investigate the evolution of synergistic trait interactions in anglerfishes, which include one of the most species-rich vertebrate clades in the bathypelagic, or "midnight," zone of the deep sea: Ceratioidea. 5 Ceratioids are the only vertebrates that possess sexual parasitism, wherein males temporarily attach or permanently fuse to females to mate. 6,7 We show that the rapid transition of ancestrally benthic anglerfishes into pelagic habitats occurred during a period of major global warming 50–35 million years ago. 8,9 This transition coincided with the origins of sexual parasitism, which is thought to increase the probability of successful reproduction once a mate is found in the midnight zone, Earth's largest habitat. 5,6,7 Our reconstruction of the evolutionary history of anglerfishes and the loss of immune genes support that permanently fusing clades have convergently degenerated their adaptive immunity. We find that degenerate adaptive immune genes and sexual body size dimorphism, both variably present in anglerfishes outside the ceratioid radiation, likely promoted their transition into the bathypelagic zone. These results show how traits from separate physiological, morphological, and reproductive systems can interact synergistically to drive major transitions and subsequent diversification in novel environments. • Resolution of anglerfish phylogeny • Anglerfishes radiated into the midnight zone during an ancient climate crisis • Complex assembly of anglerfish sexual parasitism • Complex innovations sculpted the ecological transition of bathypelagic anglerfishes Brownstein et al. reconstruct the evolutionary history of anglerfishes and show how complex trait evolution, including the origins of sexual parasitism, facilitated the invasion of this clade into the deep open ocean where they diversified in the midst of a major climate change event. [ABSTRACT FROM AUTHOR]

Adult anglerfish conduct annual migrations between spawning areas and feeding areas; for Faroese waters this migration has so far not been described. Therefore, anglerfish migration and distribution in Faroese waters was investigated by mark-recapture studies, including data storage tags, as well as data from scientific trawl surveys, commercial trawlers and gillnetters. The fish distribution was compared to hydrographical conditions such as sea surface- and bottom temperature. A clear seasonal offshore-onshore migration was observed. Anglerfish occupied shallower waters (

Batfishes of the family Ogcocephalidae are a group of Lophiiformes found in tropical and subtropical marine waters with specific morphological adaptations for a deep-water benthic lifestyle. This study, morphologically and genetically documents the range extension of Indo-Pacific batfish, Halieutaea indica into the northern marginal waters of the Indian Ocean (Gulf of Oman), and confirms the presence of more shared fish elements of the Gulf of Oman with the Indian Ocean. DNA barcoding based on the mitochondrial COI gene sequence revealed that the collected batfish specimens from the Gulf of Oman are conspecific with H. indica. [ABSTRACT FROM AUTHOR]

Abstract Objective Analyze key features of the anglerfish Lophius piscatorius mitochondrial transcriptome based on high-throughput total RNA sequencing. Results We determined the complete mitochondrial DNA and corresponding transcriptome sequences of L. piscatorius. Key features include highly abundant mitochondrial ribosomal RNAs (10–100 times that of mRNAs), and that cytochrome oxidase mRNAs appeared > 5 times more abundant than both NADH dehydrogenase and ATPase mRNAs. Unusual for a vertebrate mitochondrial mRNA, the polyadenylated COI mRNA was found to harbor a 75 nucleotide 3′ untranslated region. The mitochondrial genome expressed several non-canonical genes, including the long noncoding RNAs lncCR-H, lncCR-L and lncCOI. Whereas lncCR-H and lncCR-L mapped to opposite strands in a non-overlapping organization within the control region, lncCOI appeared novel among vertebrates. We found lncCOI to be a highly abundant mitochondrial RNA in antisense to the COI mRNA. Finally, we present the coding potential of a humanin-like peptide within the large subunit ribosomal RNA.

We validated the daily formation of increments in otoliths of yellow goosefish Lophius litulon using reared individuals to examine the growth in the field. Single, round-shaped core structures were observed in 41% of sagittae and in 73% of the lapilli. Therefore, lapillar otoliths were used for further observations of daily increment analysis. The lapillus radius of newly hatched larvae was 15.0 ± 1.4 μm (mean ± standard deviation) forming the hatch check (first check). At 6 days after hatching (DAH), the second check was observed, which may correspond to the energy transition from endogenous to exogenous nutrition, located at 28.1 ± 0.7 μm from the core structures. Thereafter, clear daily increments formed outside the check. To estimate larval growth in the field, we examined the relationship between the notochord length (NL) and lapillus radius by an allometric equation. The mean growth rate was estimated as ca. 0.18 mm in NL/day during 10–40 DAH. The results of this study provide insights into the previously unknown early life history and will enable further understanding of the population dynamics of the genus Lophius. [ABSTRACT FROM AUTHOR]

Anglerfishes are a highly diverse group of species with unique characteristics. Here, we report the first chromosome-level genome of a species in the order Lophiiformes, the yellow goosefish (Lophius litulon), obtained by whole genome shotgun sequencing and high-throughput chromatin conformation capture. Approximately 97.20% of the assembly spanning 709.23 Mb could be anchored to 23 chromosomes with a contig N50 of 164.91 kb. The BUSCO value was 95.4%, suggesting that the quality of the assembly was high. A comparative gene family analysis identified expanded and contracted gene families, and these may be associated with adaptation to the benthic environment and the lack of scales in the species. A majority of positively selected genes were related to metabolic processes, suggesting that digestive and metabolic system evolution expanded the diversity of yellow goosefish prey. Our study provides a valuable genetic resource for understanding the mechanisms underlying the unique features of the yellow goosefish and for investigating anglerfish evolution.

Anglerfishes are a highly diverse group of species with unique characteristics. Here, we report the first chromosome-level genome of a species in the order Lophiiformes, the yellow goosefish (Lophius litulon), obtained by whole genome shotgun sequencing and high-throughput chromatin conformation capture. Approximately 97.20% of the assembly spanning 709.23 Mb could be anchored to 23 chromosomes with a contig N50 of 164.91 kb. The BUSCO value was 95.4%, suggesting that the quality of the assembly was high. A comparative gene family analysis identified expanded and contracted gene families, and these may be associated with adaptation to the benthic environment and the lack of scales in the species. A majority of positively selected genes were related to metabolic processes, suggesting that digestive and metabolic system evolution expanded the diversity of yellow goosefish prey. Our study provides a valuable genetic resource for understanding the mechanisms underlying the unique features of the yellow goosefish and for investigating anglerfish evolution. [ABSTRACT FROM AUTHOR]

The deep-sea batfish genus Halieutopsis is reviewed based on worldwide collections. Sixteen species are recognized, including five newly described species: Halieutopsis echinoderma sp. nov. from eastern Taiwan and northeastern Australia, Halieutopsis kawaii sp. nov. from Taiwan and Indonesia, Halieutopsis okamurai sp. nov. from southeastern Japan, Halieutopsis murrayi sp. nov. from the Gulf of Aden, and Halieutopsis taiwanea sp. nov. from northeastern Taiwan. These species differ from their congeners in escal morphology, squamation, and morphometric proportions. Dibranchus nasutus Alcock, 1891, a senior synonym of Halieutopsis vermicularis Smith & Radcliffe, 1912, as well as Dibranchus nudiventer Lloyd, 1909 and Coelophrys oblonga Smith & Radcliffe, 1912, are recognized as valid species in Halieutopsis. Comments on the systematics and biogeographic distributions of the species of Halieutopsis are provided, along with a key to the species.

The almost complete skeleton of a fossil dreamer, identified as Oneirodes sp., is described from the middle–upper Miocene Kurasi Formation of southern Sakhalin Island, Russia. This is the second fossil skeletal record of oneirodid anglerfishes following those described from the Puente Formation of California, USA. The new specimen possesses morphological features very similar to those of the recent and fossil members of its genus, and cannot be separated from them at the species level. This finding confirms the idea of the high level of speciation of this fish family prior to the middle–late Miocene and demonstrates the wide geographic distribution of the genus Oneirodes already at this time. [ABSTRACT FROM AUTHOR]

Objective: Analyze key features of the anglerfish Lophius piscatorius mitochondrial transcriptome based on high-throughput total RNA sequencing. Results: We determined the complete mitochondrial DNA and corresponding transcriptome sequences of L. piscatorius. Key features include highly abundant mitochondrial ribosomal RNAs (10–100 times that of mRNAs), and that cytochrome oxidase mRNAs appeared > 5 times more abundant than both NADH dehydrogenase and ATPase mRNAs. Unusual for a vertebrate mitochondrial mRNA, the polyadenylated COI mRNA was found to harbor a 75 nucleotide 3′ untranslated region. The mitochondrial genome expressed several non-canonical genes, including the long noncoding RNAs lncCR-H, lncCR-L and lncCOI. Whereas lncCR-H and lncCR-L mapped to opposite strands in a non-overlapping organization within the control region, lncCOI appeared novel among vertebrates. We found lncCOI to be a highly abundant mitochondrial RNA in antisense to the COI mRNA. Finally, we present the coding potential of a humanin-like peptide within the large subunit ribosomal RNA. [ABSTRACT FROM AUTHOR]

Globalisation has led to increased trade and consumption of fish worldwide. As international trade and consumption of fish increases, so does the likelihood of fish being adulterated. It is often an illegal exchange of species where a cheaper species is substituted for a more expensive and rarer one. In Europe, the anglerfish (Lophius piscatorius) is often traded as the rarer, more popular black-bellied anglerfish (Lophius budegassa). To improve our ability to monitor and detect adulterants in these fish species, we developed a real-time PCR assay that allows for the simultaneous detection and quantification of L. piscatorius and L. budegassa. The newly designed primers target the second intron of the genomic gene parvalbumin. The proposed methodology shows good robustness, efficiency and high specificity. Of the 47 species tested, only Lophius species were amplified. Their differentiation is possible by analysing melting curves with an average Tm of 70.1 °C for L. piscatorius and 75.3 °C for L. budegassa , respectively. The detection limit for both species was 0.050 ng/μl. The assay also provides a tool to quantify parvalbumin in European anglerfish. The findings point to the use of the method proposed as a potential tool in forensic investigations to prevent illegal species substitutions, mislabeling, and food fraud. • Simultaneous detection and quantification of European anglerfish. • Use of novel genomic marker targeting the second intron of parvalbumin gene. • Assay suitable as calibrants for the parvalbumin quantification of anglerfish. • Potential tool for forensic investigations, preventing mislabeling and food fraud. [ABSTRACT FROM AUTHOR]

Almost nothing is known about the diets of bathypelagic fishes, but functional morphology can provide useful tools to infer ecology. Here we quantify variation in jaw and tooth morphologies across anglerfishes (Lophiiformes), a clade spanning shallow and deep-sea habitats. Deep-sea ceratioid anglerfishes are considered dietary generalists due to the necessity of opportunistic feeding in the food-limited bathypelagic zone. We found unexpected diversity in the trophic morphologies of ceratioid anglerfishes. Ceratioid jaws span a functional continuum ranging from species with numerous stout teeth, a relatively slow but forceful bite, and high jaw protrusibility at one end (characteristics shared with benthic anglerfishes) to species with long fang-like teeth, a fast but weak bite and low jaw protrusibility at the other end (including a unique 'wolftrap' phenotype). Our finding of high morphological diversity seems to be at odds with ecological generality, reminiscent of Liem's paradox (morphological specialization allowing organisms to have broader niches). Another possible explanation is that diverse ceratioid functional morphologies may yield similar trophic success (many-to-one mapping of morphology to diet), allowing diversity to arise through neutral evolutionary processes. Our results highlight that there are many ways to be a successful predator in the deep sea.

Anglerfish, or, monkfish, (Lophius piscatorius and L. budegassa) are two of the most valuable commercial fish species in northern Europe. The stock which occupies the northern European shelf is monitored by an annual bottom trawl survey which aims to estimate absolute abundance. This estimation includes corrections for herding by the trawl gear but also requires an estimate of the capture efficiency of the net. To determine the latter, losses of fish under the footrope were quantified by 1 cm length class using trawls fitted with sub-footrope collection bags. The results demonstrate clear length dependency with the smallest fish being the most likely to escape under the gear. Overall, approximately 27 % of the anglerfish were lost under the footrope, with approximately 77 % of those below 30 cm being found in the ground gear collection bags. A length-based retention model for the gear was fitted here with a day-night effect, following appropriate model selection. This estimated higher proportions of fish escapes at night than during the day. The model was then used to estimate total stock numbers at length using data from the 2006 monkfish survey data to examine their impact on the stock estimates. As expected, this demonstrated a significant increase in the abundance of smaller recruiting fish when escapement under the footrope is accounted for. The estimates at length and age will provide better inputs for future developments of an age- or length-based analytical stock assessment which in turn will contribute to better stock management. [Display omitted] • Smaller fish are more likely to escape under survey trawls. • Sub-footrope collection bags can retain these escapees. • A length-based retention curve was fitted with a day-night effect. • Higher proportions of fish escaped at night. • Accounting for footrope escapement increased abundance estimates significantly. [ABSTRACT FROM AUTHOR]

Several studies in the last 20 years have revealed that morphological asymmetry in fish can be characterized as 'antisymmetry'. Antisymmetry is a lateral dimorphism in which each population consists of individuals with well-developed left sides (lefties) and well-developed right sides (righties). This dimorphism influences predator-prey interactions. In some piscivorous fishes, it has been found that predators can catch more prey of the opposite morphological type to themselves (cross-predation) than of the same morphological type (parallel-predation). Our previous work clarified that the predominance of cross-predation is caused by lateralized behaviors of predators and prey that correspond to their morphological antisymmetry. Moreover, based on the results of our behavioral observations, we hypothesized that parallel-predation can predominate when predators encounter the potential prey frontally. To test this hypothesis, in the present study we investigated the relationship between lateral morphological types of anglerfish ( Lophiomus setigerus) and those of the prey fishes found in their stomachs. Anglerfish attract potential prey using their first dorsal fin (illicium) as a lure, and their frontal encounters with potential prey fishes were photographed in situ and observed in an aquarium. The results of a stomach contents analysis indicated that parallel-predation predominated in five benthopelagic prey fish species (perches and eels). By contrast, five benthic prey fishes (gobies and weevers) exhibited the predominance of cross-predation. These results not only demonstrate the predominance of parallel-predation in a natural fish community, but also suggest that the relationship between morphological types of predator and prey species can be reversed depending on the lifestyle of prey. [ABSTRACT FROM AUTHOR]

The goosefish, Lophius americanus , is a dorso-ventrally compressed marine fish that spends most of its life sitting on the substrate waiting to ambush prey. Species in the genus Lophius have some of the slowest ventilatory cycles recorded in fishes, with a typical cycle lasting more than 90 s. They have a large gill chamber, supported by long branchiostegal rays and ending in a siphon-like gill opening positioned underneath and behind the base of the pectoral fin. Our goals were to characterize the kinematics of gill ventilation in L. americanus relative to those of more typical ray-finned fishes, address previous assertions about ventilation in this genus, and describe the anatomy of the gill opening. We found that phase 1 of ventilation (during which both the buccal and gill chamber are expanding) is greatly increased in duration relative to that of typical ray-finned fishes (ranging from 62 to 127 s), and during this phase, the branchiostegal rays are slowly expanding. This slow expansion is almost visually imperceptible, especially from a dorsal view. Despite this unusually long phase 1, the pattern of skeletal movements follows that of a typical actinopterygian, refuting previous assertions that Lophius does not use its jaws, suspensorium, and operculum during ventilation. When individuals were disturbed from the sediment, they tended to breathe more rapidly by decreasing the duration of phase 1 (to 18–30 s). Dissections of the gill opening revealed a previously undocumented dorsal extension of the adductor hyohyoideus muscle, which passes from between the branchiostegal rays, through the ventro-medial wall of the gill opening, and to the dorsal midline of the body. This morphology of the adductor hyohyoideus shares similarities with that of many Tetraodontiformes, and we suggest that it may be a synapomorphy for Lophiiformes + Tetraodontiformes. The specialized anatomy and function of the gill chamber of Lophius represents extreme modifications that provide insight into the potential limits of the actinopterygian gill ventilatory system. [ABSTRACT FROM AUTHOR]

A multiple approach to the growth of Lophius vomerinus is presented for the first time, based on age estimation of 2282 illicia (first dorsal fin ray) sections, length-frequency analyses (SLCA, ELEFAN, Bhattacharya) and corroborated by tracking cohorts. The growth is studied based on the widest time series (2000–2017) and the largest sample analyzed to date. Individuals ranging from 3 to 109 cm, representing the whole range commercially landed, were collected from annual research surveys in Namibian waters. Modification in the age interpretation using illicia is presented, suggesting a new more accurate criterion at early ages. Two main different growth patterns were obtained, being that of the length-frequency analyses faster than from illicia age estimation. Both growth patterns estimated here are faster than those from previous studies. Possible causes of differences among all studies are discussed. The von Bertalanffy growth parameters from illicia age estimation (L ∞ = 110, k = 0.08, t 0 = −1.16) are proposed to be used in age-structured models for the annual assessment of this population. Growth pattern provides tracking of cohorts in the abundance-at-age matrix, with high correlation values obtained between the age abundance indices of the same year-class for most of the age groups compared. Greater lengths and ages were found in females, showing a slightly higher growth rate than males in older specimens. • Multiple approach to the growth pattern of monkfish in Namibian waters. • Age estimation based on illicia and length-frequency analyses performed. • Growth parameters corroborated by tracking cohort abundance in surveys. • New growth patterns estimated are faster than those from previous studies. • Growth parameters available for upcoming stock assessment. [ABSTRACT FROM AUTHOR]

The chorion surface ultrastructure of unfertilized eggs of black anglerfish Lophius budegassa and white anglerfish Lophius piscatorius was examined by scanning electron microscopy. Species-specific differences were observed. [ABSTRACT FROM AUTHOR]

Growth increments in the lapilli otoliths of the black anglerfish ( Lophius budegassa ) were used to investigate its early life history. Assuming that the primary increments are deposited daily, age and hatch dates were determined by counting these increments in the lapilli of 33 juvenile fish collected during autumn bottom trawl surveys in the Bay of Biscay. The estimated ages of juveniles ranged from 71 to 165 days (60 to 202 mm total length) while the growth rate ranged from 1.19 to 1.48 mm day −1 for that period. The age–length relationship was best described by the power function TL = 0.311 age (days) 1.26 . Hatch date was back-calculated from the date of capture and results indicate a broad spawning season, mainly taking place from May to July. Juveniles of up to 200 mm total length collected in October were born the same year and belonged to age class 0. Although the periodicity of the primary increments has not yet been validated, our results, based on this assumption, would corroborate, for the first time using micro-increment analysis, a faster growth pattern of early stages of L. budegassa in Atlantic waters than previously thought, in agreement with the evidence obtained for the species in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

The reproduction of black anglerfish ( Lophius budegassa ) was studied from samples collected during 5 years, from January 2006 to December 2010, in Celtic Sea, West and South of Ireland (ICES Div. VIIb–k) and Northern Spanish Atlantic waters (ICES Div. VIIIc–IXa). A total of 1167 specimens (4–99 cm) were sampled. The sex ratio, the spawning period and the maturity ogives by length were studied. The sex ratio in both areas studied varied with length, and it was close to 1:1 (male:female), 1:1.22 (54.90% of females) in Div. VIIb–k, and 1:1.01 (50.30% of females) in Div. VIIIc–IXa. A seasonal variation in sex ratio by length was observed at first time in Div VIIIc–IXa, with a very low proportion of intermediate sized females (40–60 cm) in the second semester. A seasonal reproductive migratory behavior is discussed. The spawning period was between December and July in Div. VIIIc–IXa. Spawning males were found throughout the year, but fewer spawning females, as in previous studies. The L50 values were estimated in Div. VIIIc–IXa: 38.2 cm for combined sexes, 36.0 cm for males and 53.0 cm for females. These values of sex ratio and L50 are similar to those obtained in closed areas studied. [ABSTRACT FROM AUTHOR]

The deep-sea batfish genus Halieutopsis is reviewed based on worldwide collections. Sixteen species are recognized, including five newly described species: Halieutopsis echinoderma sp. nov. from eastern Taiwan and northeastern Australia, Halieutopsis kawaii sp. nov. from Taiwan and Indonesia, Halieutopsis okamurai sp. nov. from southeastern Japan, Halieutopsis murrayi sp. nov. from the Gulf of Aden, and Halieutopsis taiwanea sp. nov. from northeastern Taiwan. These species differ from their congeners in escal morphology, squamation, and morphometric proportions. Dibranchus nasutus Alcock, 1891, a senior synonym of Halieutopsis vermicularis Smith & Radcliffe, 1912, as well as Dibranchus nudiventer Lloyd, 1909 and Coelophrys oblonga Smith & Radcliffe, 1912, are recognized as valid species in Halieutopsis. Comments on the systematics and biogeographic distributions of the species of Halieutopsis are provided, along with a key to the species. [ABSTRACT FROM AUTHOR]

Abstract: The age of white anglerfish (Lophius piscatorius) on the Porcupine Bank was estimated based on the age estimation of 979 illicia (first dorsal fin ray) obtained from a series of 9 annual groundfish surveys (2001–2009). Modifications in the methodology of illicia preparation and in the traditional biased age estimation criterion are presented. This is the first time that a growth pattern of white anglerfish based on illicia age estimations can be indirectly validated by tracking cohorts using the abundance indices per age class from surveys and length-frequency analyses. Previous studies of cohort tracking using the traditional illicia age estimation criterion showed a mismatch, suggesting a faster growth. With the new proposed criteria, abundant cohorts from 2001 to 2004, and scarce ones, from 2005 to 2007, can be tracked over the time throughout several age groups. A new growth pattern and von Bertalanffy growth parameters are presented (L ∞: 162.31; k: 0.088; t 0: −0.894). The results are compared with previous studies in other areas. [Copyright &y& Elsevier]