Heterocarpus Ensifer Research Articles

An Aggregation of the Pandalid Shrimp, Heterocarpus ensifer, on Deep Reef Habitats of the West Florida Slope, Eastern Gulf of Mexico

An Aggregation of the Pandalid Shrimp, Heterocarpus ensifer, on Deep Reef Habitats of the West Florida Slope, Eastern Gulf of Mexico

Complete mitochondrial genomes of two deep-sea pandalid shrimps, Heterocarpus ensifer and Bitias brevis: insights into the phylogenetic position of Pandalidae (Decapoda: Caridea)

The mitochondrial genome (mitogenome) analysis is a significant tool for investigating the evolutionary history of metazoan animals. The family Pandalidae is a diverse caridean group containing mainly deep-sea species. Until May 30 2019, only two complete mitogenomes are available in GenBank. Here we present the complete mitogenome sequences of two deep-sea pandalid shrimps, Heterocarpus ensifer and Bitias brevis through Illumina sequencing. The mitochondrial genomes were determined to be 15 939 bp and 15 891 bp long, and both consist of 13 protein-coding genes (PCGs), 23 transfer-RNA genes (tRNAs), two ribosomal-RNA genes (rRNAs), and one control region. The nucleotide composition is biased toward adenine and thymine. Overall, the gene contents and arrangements are consistent with the pancrustacean ground pattern. The alignment of the control regions of four pandalids reveals a conserved sequence block (CSB) (104 bp in length, average GC%=29.47% and 69.23% similarity). A phylogenetic analysis based on 51 Caridea complete mitogenomes revealed that the deep-sea pandalid shrimps are situated an intermediate lineage, with a tendency to originated from those living in shallow sea area.

Bioaccumulation of chemical warfare agents, energetic materials, and metals in deep-sea shrimp from discarded military munitions sites off Pearl Harbor

The bioaccumulation of munitions-related chemicals at former military deep-water disposal sites is poorly understood. This paper presents the results of human-food-item biota sampling to assess the potential for bioaccumulation of chemical warfare agents, energetic materials, arsenic, and additional munitions-related metals in deep-sea shrimp tissue samples collected during the Hawai‘i Undersea Military Munitions Assessment (HUMMA) project to date. The HUMMA investigation area is located within a former munitions sea-disposal site located south of Pearl Harbor on the island of O‘ahu, Hawai‘i, designated site Hawaii-05 (HI-05) by the United States Department of Defense. Indigenous deep-sea shrimp (Heterocarpus ensifer) were caught adjacent to discarded military munitions (DMM) and at control sites where munitions were absent. Tissue analysis results showed that chemical warfare agents and their degradation products were not present within the edible portions of these samples at detectable concentrations, and energetic materials and their degradation products were detected in only a few samples at concentrations below the laboratory reporting limits. Likewise, arsenic, copper, and lead concentrations were below the United States Food and Drug Administration׳s permitted concentrations of metals in marine biota tissue (if defined), and their presence within these samples could not be attributed to the presence of DMM within the study area based on a comparative analysis of munitions-adjacent and control samples collected. Based on this current dataset, it can be concluded that DMM existing within the HUMMA study area is not contributing to the bioaccumulation of munitions-related chemicals for the biota species investigated to date.

Fishing methods for sustainable shrimp fisheries in the Canary Islands (North-West Africa)

During the past 20 years, experimental cruises have been conducted around the Canary Islands (North-West Africa) to investigate the biodiversity of the deep-sea ecosystem and to explore new fisheries resources. Although pandalid shrimps were shown to be very abundant in this region, information is lacking regarding the best fishing method for catching the different species of shrimp. Here, two types of traps were tested, a semi-floating shrimp trap and a traditional bottom trap, in an effort to improve the fishing gear effectiveness and to reduce the capture of non-target species. In total, nine species were captured, which were categorised into three main groups based on their depth of capture: Plesionika edwardsii, P. narval and P. holtuisi (100–400 m); P. ensis, P. martia, P. williamsi and Heterocarpus ensifer (400–800 m); and H. grimaldii and H. laevigatus (800–1 300 m). Significant differences were found in the capture of the different species: P. narval, P. ensis, P. edwardsii and H. ensifer were captured more readily using the semi-floating traps, whereas P. martia, P. williamsi, H. grimaldii and H. laevigatus were caught more efficiently with traditional bottom traps. This intra-specific difference in their capture was considered to be due to the differential motility of the species in the water column. There were indications that P. edwardsii and H. ensifer are an unexploited resource that has the potential to support a viable and sustainable fishery using semi-floating shrimp traps. Furthermore, the deeper-dwelling pandalid shrimps, H. laevigatus and H. grimaldi, could be a secondary target species using bottom traps.

Light and vision in the deep-sea benthos: I. Bioluminescence at 500–1000 m depth in the Bahamian Islands

Bioluminescence is common and well studied in mesopelagic species. However, the extent of bioluminescence in benthic sites of similar depths is far less studied, although the relatively large eyes of benthic fish, crustaceans and cephalopods at bathyal depths suggest the presence of significant biogenic light. Using the Johnson-Sea-Link submersible, we collected numerous species of cnidarians, echinoderms, crustaceans, cephalopods and sponges, as well as one annelid from three sites in the northern Bahamas (500-1000 m depth). Using mechanical and chemical stimulation, we tested the collected species for light emission, and photographed and measured the spectra of the emitted light. In addition, in situ intensified video and still photos were taken of different benthic habitats. Surprisingly, bioluminescence in benthic animals at these sites was far less common than in mesopelagic animals from similar depths, with less than 20% of the collected species emitting light. Bioluminescent taxa comprised two species of anemone (Actinaria), a new genus and species of flabellate Parazoanthidae (formerly Gerardia sp.) (Zoanthidea), three sea pens (Pennatulacea), three bamboo corals (Alcyonacea), the chrysogorgiid coral Chrysogorgia desbonni (Alcyonacea), the caridean shrimp Parapandalus sp. and Heterocarpus ensifer (Decapoda), two holothuroids (Elasipodida and Aspidochirota) and the ophiuroid Ophiochiton ternispinus (Ophiurida). Except for the ophiuroid and the two shrimp, which emitted blue light (peak wavelengths 470 and 455 nm), all the species produced greener light than that measured in most mesopelagic taxa, with the emissions of the pennatulaceans being strongly shifted towards longer wavelengths. In situ observations suggested that bioluminescence associated with these sites was due primarily to light emitted by bioluminescent planktonic species as they struck filter feeders that extended into the water column.

Early larval morphology of the armed nylon shrimp Heterocarpus ensifer ensifer A. Milne-Edwards, 1881 (Decapoda, Caridea, Pandalidae) from laboratory culture

Early larval morphology of the armed nylon shrimp Heterocarpus ensifer ensifer A. Milne-Edwards, 1881 (Decapoda, Caridea, Pandalidae) from laboratory culture

Reproductive traits of tropical deep-water pandalid shrimps ( Heterocarpus ensifer) from the SW Gulf of Mexico

Heterocarpus ensifer is a tropical deep-water pandalid shrimp whose reproductive features are poorly known. We examined reproductive traits of a population of H. ensifer inhabiting the continental slope (311–715 m in depth) off the Yucatan Peninsula, Mexico (SW Gulf of Mexico). Size range of the total sample ( n=816) was 10.4–38.9 mm carapace length. Females grow larger than males, but both sexes mature at 57% of their maximum theoretical size and at ∼30% of their total lifespan. Among adult females, the proportion of ovigerous females was high in all seasons, indicating year-round reproduction. Most females carrying embryos in advanced stages of development had ovaries in advanced stages of maturation, indicating production of successive spawns. In the autumn, however, the proportion of ovigerous females and the condition index of these females were lower compared to other seasons. This pattern potentially reflects a reduction in food resources following the summer minimum in particulate organic carbon flux to the deep benthos, as reported in previous studies. Spawns consisting of large numbers (16024±5644, mean±SD) of small eggs (0.045±0.009 mm 3) are consistent with extended planktotrophic larval development, an uncommon feature in deep-water carideans. Egg number increased as a power function of female size but with substantial variability, and egg size varied widely within and between females. There was no apparent trade-off between egg number and egg size and neither of these two variables was influenced by female condition. These results indicate iteroparity and a high and variable reproductive effort, reflecting a reproductive strategy developed to compensate for high larval mortality. The present study provides a baseline to compare reproductive traits between Atlantic populations of this tropical deep-water pandalid.

Early larval morphology of the armed nylon shrimp Heterocarpus ensifer ensifer A. Milne-Edwards, 1881 (Decapoda, Caridea, Pandalidae) from laboratory culture

The first four zoeal stages of the shrimp Heterocarpus ensifer ensifer were obtained under laboratory conditions. The morphology of each larval stage was described and illustrated in detail. The Heterocarpus's larval features fit into the characteristics of the family Pandalidae, and indicate a close relationship with the genus Plesionika.

Biology of the Deep-Water Shrimp Heterocarpus Ensifer (Caridea: Pandalidae) Off the Canary, Madeira and the Azores Islands (Northeastern Atlantic)

An analysis of size and reproduction of Heterocarpus ensifer (Caridea: Pandalidae) off the Macaronesian archipelagos (Canary, Madeira, and the Azores islands, northeastern Atlantic) is done. The size range of samples was similar among the archipelagos studied, around |$9-39{\text{ mm}}$| carapace length (CL). The carapace length/wet weight relationship showed a negative allometry in males and varied in females. One-way analysis of regression slopes |$(b)$| among archipelagos pointed out significant differences in all groups with the exception of males. Growth parameters indicated that males are smaller in size, but grow faster than females. Growth performance |$(\Phi{\text{’}})$| estimates varied between 2.69 and 2.81, pointing out a very similar growth pattern among regions. Ovigerous females were present in all months sampled with a mass spawning period in spring and summer, which are the seasons when the water is warmer. Size at maturity was estimated in |$22.4{\text{ mm CL}}$| for the Canary Islands and |$25.7{\text{ mm CL}}$| for Madeira. In general, the life history of this deep-water species is similar in the three archipelagos.

Relative growth and size at first maturity of the deep water shrimp,Heterocarpus Ensifer (Decapoda, Pandalidae) from the southern Gulf of Mexico

The pandalid shrimp, Heterocarpus ensifer occurs on continental slopes over the eastern and western Atlantic, and over some portions of the Indian and Pacific oceans. Despite its wide distribution, studies on the biology of this species are scant. In particular, there is no information on morphometric relationships or reproductive issues from any western Atlantic population. Although the general morphology of males and females of H. ensifer appears similar, we hypothesized that size at the onset of sexual maturity (SOM) and sexual dimorphism of H. ensifer could be examined with morphometric analyses, using those body dimensions most commonly measured in shrimp: carapace length (CL), body length (BL), rostral length (RL), and body weight (BW). We examined 754 H. ensifer from the southern Gulf of Mexico. SOM, determined through sequential reduced major axis regressions of BL, RL, relative rostral length (RRL = RL/CL), and BW against CL, was 23-24 mm CL in females and 21-22 mm CL in males. These sizes closely matched those of the smallest ovigerous females and the smallest males with appendices masculinae. Juveniles of both sexes showed similar morphometry and allometries, but ontogenetic allometry and morphometric sexual dimorphism occurred after maturity. In particular, the positive relationship (with negative allometry) between RL and CL shown in juveniles was lost after SOM in females and changed to enantiometry in males, despite a wide dispersion of data. The rostral polymorphism may be related to the protracted, year-round reproductive activities of this Gulf of Mexico population. Morphometric techniques may be useful to compare populations of if. ensifer from disparate locations.

On the presence of Heterocarpus ensifer Milne Edwards, 1881 (Decapoda, Pandalidae) in the Spanish Mediterranean

On the presence of Heterocarpus ensifer Milne Edwards, 1881 (Decapoda, Pandalidae) in the Spanish Mediterranean

Considerations on the biology of <i>Plesionika edwardsi</i> (Brandt, 1851) (Decapoda, Caridea, Pandalidae) from experimental trap catches in the Spanish western Mediterranean Sea

In this study, the results obtained from three experimental trap shrimp (Plesionika edwardsi) fishing cruises in three different seasons are presented. They were carried out during a total of 50 days, of which 43 days were of effective fishing, covering the whole Spanish Mediterranean coast including the island of Alboran. On the whole, the fishing depth varied between 220 and 384 m, with a mean depth of 318 m. The target species appeared in 81% of the total samples carried out, with a mean yield (cpue) of 108.6 g/trap/day. The largest yields (cpue) of this species were from the Balearic islands, followed by Levant region, whereas the Alboran sea gave the lowest yields. The largest mean length was observed on the Levant zone, but on the contrary the smallest mean lengths were found towards the south, more specifically at Alboran island. Significant differences were found in both the relative and absolute growth, between males and females, with equilibrium in the ratio of the sexes (0.49). A total of 15 crustacean and 12 fish species were identified as accompanying fauna, with Conger conger, Plesionika narval and Scyliorhinus canicula being the most important, based on their mean cpue, although differences in the appearance and yields of the species were found in the different zones and depths. However, the mean yields of these species were very low, due to the high selectivity of the fishing gear used. The appearance of Heterocarpus ensifer, deserves a special mention, since it is the second documented record of the species in the Mediterranean.

Shrimps of the family Pandalidae (Crustacea, Decapoda) off the Canary Islands, Eastern Central Atlantic

The geographic and bathymetric distribution and habitat of shrimps of the family Pandalidae in the Eastern Atlantic (23–36°N), particularly the Canary Islands, are reviewed. The most abundant species is Plesionika narval, followed by Plesionika edwardsi and Heterocarpus ensifer. Bitias stocki is recorded for the first time from the Canary Islands. Information on size and depth distributions of pandalid species from the Macaronesian archipelagos are provided. Zoogeographic comments on the Pandalidae of the Canary Islands are given. The probable presence of species not yet found around these islands, but which occur in surrounding regions, is discussed.

Relationship of life-history patterns to depth in deep-water caridean shrimps (Crustacea: Natantia)

Deep-water shrimps, distributed on the steep outer reef slopes of tropical Pacific Islands, were obtained by setting baited traps in depths down to 850 m in the vicinity of Laucala Bay, Fiji, over the period 1979 to 1983. Life-history variables were estimated and interspecific comparisons made between Parapandalus serratifrons, Plesionika longirostris, Heterocarpus ensifer, H. gibbosus, H. sibogae, H. laevigatus (Pandalidae) and Saron marmoratus (Hippolytidae) which have different depth distributions. Results suggested that, interspecifically, reproductive lifespan tended to increase with increasing depth of distribution and that mean egg sizes of each species increased with increasing depth. Brood sizes tended to increase inconsistently with depth, although relative brood size (number of eggs per “standar” 15 g individual) appeared unrelated to depth. Although annual reproductive effort varied inconsistently with depth, reproductive effort totalled over the lifespan of the Heterocarpus species tended to increase with increasing depth. Some of the findings are counter to competition-based ecological theory, and it is proposed that adult predation decreases with increasing depth, allowing deeper-water species to have an extended lifespan, an increased degree of iteroparity, and a corresponding increase in lifetime reproductive effort. Further, we suggest that the probabilities of larval survival, which appear to decrease with increasing depth, are offset by the production of larger eggs by deeper-water species.

Nearshore dredge-spoil dumping and cadmium, copper, and zinc levels in a dermestid shrimp.

Dumping of dredge spoil in nearshore waters is seen as an economically viable method of disposing of large volumes of essentially useless material. This method becomes especially attractive when examined in the perspective of an island situation where land is scarce, costly, and primarily limited to residential and other priority properties. The long-term impact of the operation on the ecological stability of aquatic communities, however, is uncertain. In light of man's growing use of the ocean as a repository for waste materials, the need to understand these impacts is increasingly urgent. A dermestid shrimp of potential commercial importance, Heterocarpus ensifer, was chosen as an indicator organism to monitor possible changes in population characteristics and to observe potential changes in the retention of certain environmentally important metal residues. Ecological dynamics of this population are described elsewhere (CHAVE & MILLER 1977). Cadmium, copper, and zinc residue levels were evaluated in a control-site population and a dredge spoil dumping-site population over a period of two years active dumping to determine any modification in the bioaccumulation of these metals.

Decapod Crustacea from the International Indian Ocean Expedition: the larval development of Heterocarpus (Caridea)

The larval species Atlantocaris gigas Ortmann is shown to be conspecific with Heterocarpus ensifer A. Milne Edwards, while Procletes biangulatus Bate is the larva of Heterocarpus levicarina (Bate). Each species passes through 13–15 zoeal stages and 3–4 megalopal stages. The later zoeal stages are large, have a long toothed rostrum, a carinated carapace and dorsal abdominal spines. The carinae on the carapace are retained in the adult; the rostrum becomes shortened and the abdominal spines modified at metamorphosis. Larval characters support the retention of Heterocarpus in the Pandalidae.New information on the distribution of both species is included.