Relating abundance of purpleback flying squid Sthenoteuthis oualaniensis (Cephalopoda: Ommastrephidae) to environmental parameters using GIS and GAM in south-eastern Arabian Sea

The distribution pattern of purpleback flying squid and the relationship between its abundance and environmental variables in the south-eastern Arabian Sea were analysed using a geographical information system (GIS) and a generalised additive model (GAM). Highest abundances were observed during December and January within 10 and 13°N and 71 and 72°E around the Lakshadweep Islands. The mean abundance in the area was 4.21 tonnes/km² and the maximum sustainable yield (MSY) was estimated as 0.63 million tonnes. GAM indicated that very high squid abundance was associated with low values of dissolved oxygen (6.01–6.27 mg/L), sea surface temperature (28.03–28.62°C), pH (7.75–8.56), salinity (30.42–34.48 psu), chlorophyll-a (0.4–0.6 mg/m³), zooplankton biomass (0.23–0.64 mL/m³), and shallow 20°C isotherm (101.2–134.7 m) and mixed layer depth (17.8–29.8 m). As a carnivore from paralarval stages, S. oualaniensis depends on secondary and tertiary production to sustain its population for which primary production is used up. In the tropical Arabian Sea where temperature differences are not so pronounced, S. oualaniensis distribution was found to be related to a low but very narrow sea surface temperature (SST) band. There is sufficient fishable biomass in the area to possibly launch a new targeted oceanic squid fishery from the western seaboard of India.     

Effect of tropical monsoon on fishery abundance of Indian squid (Uroteuthis (Photololigo) duvaucelii)

Indian squid, Uroteuthis (Photololigo) duvaucelii (Loliginidae) constitute an important component of the inshore cephalopod fisheries along the eastern Arabian Sea. Local environmental variation plays an important role in species–environment interactions in neritic squids, which inhabit nearshore/coastal waters. Such ‘active’ and ‘passive’ responses of squids to environmental changes is crucial in understanding their relationships and influence on the biological processes, distribution and abundance of the fast-growing short-lived coastal loliginids. The empirical relationship between squid abundance and the variability in rainfall and sea surface temperature (SST) were explored in a tropical monsoon fishery. Monthly catch rates (catch per fishing hour) of squids in commercial trawl during 1987–2009 were used as the abundance index. Linear regression models with ARIMA errors were fitted with catch per unit hour time series as dependent variable and rainfall and SST as exogenous variables. While rainfall was observed to have a negative effect on squid abundance, the SST recorded a positive impact. ARIMA models provided satisfactory fit to observed data and forecast of 22 months. Given that the squid life-cycle is a function of their environment, this result is relevant in forecasting squid biomass for the management of tropical monsoon fisheries.     

Stephonyx californiensis sp. nov. (Amphipoda: Lysianassoidea: Uristidae), a new bathyal scavenger species from the Central Gulf of California,Mexico, and comments on the bathymetric and geographic distribution of the Stephonyx species group

A new species of scavenger amphipod of the genus Stephonyx is described and illustrated. The specimen was caught at 1150 m depth with a modified rectangular lobster trap positioned on the sea bottom in the central Gulf of California, Mexico. The new species is characterised by the absence of eyes; the lateral cephalic lobes medially developed and acute; antennae subequal in length; gnathopod 1 chelate, dactylus simple with three distal stout setae, inner margin sinuous with minute setae; gnathopod 2 subchelate, carpus with ventral margin crenulate, propodus subovate, palm deeply excavate, and dactylus slightly shorter than palm; maxilliped inner plate laceolate, with seven marginal nodular robust setae, distally; telson, each lobe with two dorsal robust setae, distal margin truncated, with one penicillate and two simple setae, in addition to two short spines. Stephonyx californiensis sp. nov. is morphologically similar to S. arabiensis, S talismani, S. laqueus and S. perexcavatus. The new species increases the number of Stephonyx species around the world to 14, with one species inhabiting from the continental shelf to abyssal depths (to 3000 m), 11 species occurring in bathyal depths (201–2000 m), and two other species restricted to abyssal depths (2001–4000 m).

www.zoobank.org/urn:lsid:zoobank.org:pub:346C3B15-E56A-4E17-9C5F-C9FDBB2AED92     

Abundance and diversity of decapod crustaceans in the deep-Catalan Sea (Western Mediterranean)

The deep-slope decapod fauna of the Catalan Sea was extensively sampled with an OTSB-14 bottom trawl. A total of 67 bottom tows were taken from 1985 to 1989 at bottom depths ranging from 552 to 2261 m. Species in which abundance decreased with depth were Plesionika acanthonotus, Polycheles typhlops, Calocaris macandreae and Geryon longipes. Highest densities of Acanthephyra eximia, Stereomastis sculpta, and Nematocarcinus exilis were attained at the greatest depths studied. Total abundance, biomass and species richness for decapod crustaceans as a whole decreased with depth. Maximum decapod biomass and diversity occurred on the upper-middle slope on soft bottoms in the Catalan Sea and in all regions for which data were available. In the Catalan Sea, an oligotrophic area, the abundance of decapods as a group seemed to be higher than in north-Atlantic eutrophic regions. In these latter areas, other deep-sea benthic invertebrate groups, particularly ophiuroids, predominate.     

Prey choice and raiding behaviour of the Ponerine ant Pachycondyla analis (Hymenoptera: Formicidae)

Termite raiding behaviour of the African poneromorph ant Pachycondyla analis was studied at Mpala, Kenya. In all, 330 raids were observed with the raiding activity showing peaks in the morning and evening. Time spent at the termite source was positively correlated with the numbers of termites taken. The sizes of foraging parties, number of termites taken, distance travelled and time spent at termite sources also showed a positive correlation. Pachycondyla analis preyed significantly more on Microtermes spp. than they did on Odontotermes spp. but no significant differences were found in terms of predator efficiency even though many ants were injured in raids on Odontotermes spp. compared with those on Microtermes spp. Our results indicate that P. analis seems to forage optimally, balancing the costs of energy with prey reward and prey choices were not only influenced by prey abundance, but also by the costs of foraging, as influenced by prey defences, size and foraging behaviour.     

Bathyal cumaceans of the Catalan Sea (North-western Mediterranean): faunistic composition,diversity and near-bottom distribution along the slope (between 389 and 1859 m)

Deep-water epibenthic/suprabenthic species of Cumacea were studied in the Catalan Sea (Western Mediterranean). Samples (21) were taken at depths from 389 to 1859m, using a Macer-GIROQ type sledge, 32 cumacean species were collected. Diastyloides serratus and Leucon longirostris were the commonest species on the upper slope and middle slope, respectively. On the lower slope (1250–1859 m) dominance by any single species was not apparent and Cyclaspis longicaudata, Procampylaspis bonnieri and Platysympus typicus were the most abundant species. Two leuconids (Leucon cf. serratus, and Leucon (Crymoleucon) sp. A) were recorded for the first time in the Mediterranean Sea. The highest total abundance of cumaceans was encountered over the middle slope. Highest values of species richness and diversity (H') were registered at intermediate depths on the lower slope (1250–1355 m). The low H' value on the middle slope was attributable to the dominance of L. longirostris. Swimming coefficients calculated from near-bottom samples revealed intraspecific differences in the most abundant species. Thus, while mancas, juveniles, immature males and females, and adult females were captured almost exclusively in the lower level of the sledge, adult males of L. longirostris swam in the water column indistinctly between 10 and 140cm above the bottom. Similar trends, although less evident, have been established for other deep-sea cumaceans.     

Population characteristics of four deep‐water pandalid shrimps (Decapoda: Caridea) in the northern Aegean Sea (NE Mediterranean)

The population characteristics of four deep‐water pandalid shrimps (Decapoda: Caridea) were studied in the northern Aegean Sea in samples collected annually (1997–2000) in summer, through experimental trawl, at depths down to 600 m. Females were larger than males in Plesionika martia and Plesionika heterocarpus; no significant differences in size of males and females were found in Chlorotocus crassicornis and Plesionika antigai. A trend of increasing size with depth was observed, as well as a linear increase in the proportion of females with increasing size. Sex ratio was skewed towards females at all depths in P. antigai, while in P. heterocarpus and C. crassicornis males dominated the intermediate depths. Negative allometries were apparent in the carapace length–weight relationships in males of all species. Isometric relationships were found in females apart from in P. heterocarpus. The population patterns conform to relevant Mediterranean reports. However, some population differences exist that may reflect the distinct environmental conditions prevailing in the study area.     

Arboreality predicts Batrachochytrium dendrobatidis infection level in tropical direct-developing frogs

Pathogen-mediated changes in host behaviour can result from hosts altering their habitat preferences. Although infection risk with pathogenic fungus Batrachochytrium dendrobatidis in amphibians is associated with environments favouring its growth, the relationship with microhabitat use has not been examined. Here, we aim to determine if microhabitats used by frogs during their nocturnal activity predict B. dendrobatidis prevalence and infection intensity. Our focal host, Eleutherodactylus coqui, is a habitat generalist that uses multiple habitats from the forest floor to the canopy. We analysed data on B. dendrobatidis occurrence in 157 adults and 122 juveniles at El Yunque National forest in Puerto Rico. We categorized each individual’s nocturnal microhabitat as forest floor, curled palm fronds in the floor, arboreal bromeliads and foliage or tree trunks 50 cm to 2.5 m above ground. We found that frogs on the forest floor had the greatest B. dendrobatidis prevalence (73%), compared with those active in vegetation above ground (55%). Overall, the probability of B. dendrobatidis infection in frogs using microhabitats on the forest floor was twice as great as for those on arboreal substrates. Differences in B. dendrobatidis prevalence and intensity in E. coqui may be explained by specific abiotic conditions of microenvironments (temperature and humidity) affecting both pathogen and host, and by the age-specific ecological requirements of hosts. Adults were found to be most active in microhabitats where individuals had lower infection burdens, suggesting pathogen-modulated habitat choice. This work has important implications for the evolutionary dynamics of enzootic diseases and provides data that may inform potential mitigation strategies against a generalist amphibian pathogen.     

Reproductive biology of the endangered wattled curassow (Crax globulosa; Galliformes: Cracidae) in the Juruá River Basin,Western Brazilian Amazonia

The reproductive biology of Crax globulosa is virtually unknown, this knowledge comprised of only a few anecdotal notes. We found nine nests of Crax globulosa in the middle section of the Juruá River, western Brazilian Amazon, during the dry season. Nests averaged 22.5 m from water and 13.3 m above the ground. We observed two nest types: five made of twigs, leaves and vines, and four within a bromeliad. All nests contained two eggs, but six (67%) were subsequently predated. A female tagged with a transmitter nested twice during the same breeding season. A chick was monitored together with its parents for > 10 months. In addition to hunting and habitat loss, nest predation could be another threat to this endangered species.     

Notes on the foraging behaviour and taxonomy of the southeast Asian termite Longipeditermes longipes (Termitidae: Nasutitermitinae)

The southeast Asian termite Longipeditermes longipes (Nasutitermitinae) forages above ground during the day in highly organised columns of workers protected by numerous soldiers. Preliminary data are presented on its foraging activity, based on observations of one colony in southern Kalimantan, Borneo. Foraging columns were observed on 7 of the 15 days, including successive days interspersed with periods of inactivity. Termites marched in columns to feeding sites along trails, reusing the same trails on successive days. Trail length varied from 7.0m to 14.5m. The termites were observed feeding on leaf litter and rotting tree trunks, and the workers displayed a division of labour between gnawing plant material and carrying the fragments back to the nest. Details are provided of soldiers and workers collected from tree canopies using insecticidal fogging. One of the two other species in the genus, L. mandibulatus, is shown to be a junior synonym of L. longipes.     

Ascidiacea (Tunicata) from deep waters of the continental shelf of Western Australia

Seventy‐eight species of Ascidiacea, including 21 new species from deeper waters (about 100 m and occasionally to about 500 m) off Western Australia appear to represent a diverse fauna not previously sampled. The relatively few solitary species taken include two possibly introduced (Styela plicata and S. clava). Large aplousobranch colonies dominate the collections. Aplousobranch species with numerous, small, deeply embedded zooids in massive three‐dimensional, vertical and often branched or stalked inflexible colonies supported by embedded sand (Polyclinindae) or calcareous spicules (Didemnidae) are common. Species with flexible stalks (enabling them to respond to prevailing currents) such as Clavelina meridionalis, Sigillina australis and S. cyanea were not taken often. Some known species (e.g. Synoicum chrysanthemum, and Atriolum tubiporum) previously considered rare were taken at these depths in significant numbers. Other unusual taxa (Pseudodiazona longigona and Condominium spp.) are recorded from new locations but do not appear to be common.     

Contribution to knowledge of the genus Haploops,a new location for Haploops lodo (Crustacea: Amphipoda: Ampeliscidae) from the bathyal North Atlantic Ocean with a complement to the description of the species

Over the last two decades, several works on the family Ampeliscidae have been published, in particular about three of the four genera in the family: Ampelisca, Byblis, and Haploops. Recently, additional material collected during the BIOFAR sampling around the Faeroe Islands and during the BIOICE sampling around Iceland, in the Bay of Biscay and the EUMELI 2 campaign along the African coasts were examined. The genus Haploops was numerous (>3500 individuals), and within this material were interesting specimens. Six of them, found at four stations about 100 km off Mauritania, have been recognized as Haploops lodo (Barnard, 1961 Barnard, J. L. 1961. Gammaridean amphipoda from depths of 400 to 6000 m.. Galathea Report, 5: 23–128.  [Google Scholar]) a bathyal and abyssal species previously seen only in the Pacific ocean offshore of the American coasts. In this article, an Atlantic H. lodo specimen representative of the Atlantic specimens is compared to the holotype. The geographical and bathymetric distribution of H. lodo in the depths of the North Atlantic and Pacific Oceans are discussed.     

Reproductive ecology of the glass frog Espadarana prosoblepon (Anura: Centrolenidae) in an urban forest of the Central Andes of Colombia

Population and reproductive behaviour aspects of the glass frog Espadarana prosoblepon are well known for populations from Central America, but similar information is lacking for populations from South America. We recorded the reproductive ecology of a population of the glass frog E. prosoblepon in the city of Armenia, Central Andes of Colombia. With weekly surveys with mark-recapture between December 2013 and November 2015, we monitored activity patterns and evaluated if the probability of males mating is associated to their body size or to chorus tenure (i.e. the number of nights a same individual is calling for attracting a mate). In addition, upon observing an amplexus, we recorded the behaviour of the individuals until oviposition and noted characteristics of egg clutch. We recorded 47 males and 32 females, nine amplexus events, eight ovipositions, and 21 egg clutches (35.4 ± 4.79 eggs per clutch, N = 29). Activity of males and females and the number of egg clutches were positively correlated to rainfall. Mating success of males was not associated to their body size, but it was positively associated to longer chorus tenure; clutches from large females had a higher number of eggs than clutches from small females. Oviposition occurred on average 3.76 ± 1.74 hours after we first observed the amplexus, occurring 93.1% of the time in fronds of Selaginella geniculata at an average height of 1.58 ± 0.44 m. After the oviposition, the male left the site, while the female remained between 30 and 45 min, partially covering the eggs. The reproductive behaviour of E. prosoblepon did not vary widely between a population in Costa Rica and our population in time to oviposition, and mating success of males associated to chorus tenure; however, in our study population we recorded a larger clutch size and the preference for S. geniculata fronds as oviposition substrate.     

The carcinofauna found in stomach contents of the flying gurnard (Dactylopterus volitans) on the continental shelf of the Campos Basin,Brazil

A total of 3109 crustaceans belonging to 50 taxa distributed in 42 families were found in 117 analysed stomachs of flying gurnard (Dactylopterus volitans). Samples were obtained in April 2008 by the R/V Gyre using a bottom trawl towed in 12 stations at 14–100 m depth on the continental shelf of the Campos Basin, Brazil. The carcinofauna was analysed and the order Calanoida (Copepoda) found to be the most important item in terms of relative abundance and frequency of occurrence, followed by the order Amphipoda (Peracarida), the infraorder Brachyura (Decapoda), the order Stomatopoda and the subclass Myodocopa (Ostracoda). In the order Calanoida, the species Pontellopsis cf. villosa (Pontellidae) represented 98.04% of total crustacean abundance. The diet of Dactylopterus volitans varied according to fish size, with higher diversity of Crustacea at smaller size classes, decreasing in larger fishes. A similar pattern regarding depth was obtained, with greater diversity of taxa in gurnard stomachs caught at shallower depths. Flying gurnard is considered a generalized carnivore of invertebrates, eating mobile macrobenthic organisms, such as crustaceans, and its diet varies with its life stage, without any specific group as its main food source.     

Chaetognaths from Alvin dives in the Santa Catalina Basin (California), with description of two new Heterokrohnia species

Six species of deep-water chaetognaths have been caught near the bottom (at about 1300 m) during four dives of the submersible Alvin in the Santa Catalina Basin (California). Although few samples were taken, they are very interesting. New morphological data are presented on a supposed very well-known planktonic species (Sagitta macrocephala) and two new benthoplanktonic species of the genus Heterokrohnia are described. Details on the morphology and reproduction of the family Heterokrohniidae, and also on the bathymetric and zoogeographic distributions of Heterokrohnia species of the ‘longidentata’ group are given.     

New insights on the external features of egg capsules and embryo development in the squid Loligo vulgaris

The embryonic development of the squid Loligo vulgaris was observed from 183 egg masses collected from special devices deployed throughout Cabrera National Park (Baleares Islands, western Mediterranean Sea). Sequence alignment analysis of the cytochrome oxidase I gene revealed that all embryos belonged to L. vulgaris. In total, 549 egg capsules were examined. Viable egg capsules (n = 420) were classified into one of five maturation stages according to the primary external features. The length of the viable egg capsules varied between 40 and 170 mm, and increased with embryonic development. The non-viable capsules (n = 129) were categorized into four groups: I (Ginger root), non-viable II and III, and empty egg capsule (IV). The percentage of non-viable capsules (i.e. grades I, II and III) was 92.25%. Empty capsules accounted for 7.75% of the total non-viable egg capsules. Embryonic development was classified into a second scale of eight stages. Egg capsule stage and embryonic stage were significantly related (n = 420; p < 0.001), facilitating the determination of the embryo developmental phase based on the outward appearance of the egg capsules. The embryo development stage based on the external features of the egg capsules might constitute an innovative tool for in situ embryological data collection. This new method is neither time consuming nor invasive, and could be helpful in fishing cruises, for scuba diving visual census in natural habitats and for laboratory culture. Slight variability in the developmental embryonic stages within egg capsules from the same egg mass was identified. The origin of this asynchrony is discussed. Chronological appearance of organs was similar to that of the six loliginid species previously examined. However, some developmental changes in the timing or rate of events (heterochronies) were observed: Hoyle’s organ was formed earlier in L. vulgaris and the appearance of ventral chromatophores was slightly delayed (2 days) compared with the other species considered.     

Aspects of the biology of the jonah crab,Cancer borealis Stimpson, 1859 in the mid-Atlantic Bight

Summary

Jonah crabs, Cancer borealis, were collected in October 1971, June 1973, and March and April 1974 during trawl surveys of the continental shelf of the mid-Atlantic Bight and the shelf and slope east of Beaufort, North Carolina. In 171 trawls made from the M/V Blesk, R/V Columbus Iselin, R/V Albatross IV and R/V Eastward, 1626 jonah crabs were captured. Crabs were contagiously distributed within a depth range of 20–400 m. Maximum abundance occurred within 150–400 m and 8–13·9°C.

Male crabs ranged from 12 to 175 mm in carapace width; females from 13 to 152 mm. Three modal size groups for males and females were recognized: 13–40 mm, 41–80 mm and 81–110 mm. There was a fourth group of male crabs over 110 mm width. Crabs 40 mm were most abundant at depths of 75–150 m; crabs 41–80 mm were not captured in depths < 150 m, but were the dominant group in strata > 150 m. Larger crabs (81–110 mm) occurred from 40 to 400 m and reached maximum numbers at 150–400 m. Male crabs ≥ 111 mm were found only in 150–400 m.

Male crabs predominated in June. Sex ratios (M:F) ranged from 1·1:1 to 17:1. In October the ratios ranged from 1:16 to 2·4:1. In March and April the ratios were 2·9:1 and 1·9:1, respectively. In most cases the ratios were significantly different from 1:1.

The species was actively moulting in June, but recent or incipient ecdysis was not observed in October. Only one recently moulted crab was noted in March.

Gonad development in June was related to size. Most crabs ? 80 mm width were undeveloped or only slightly developed. Mature gonads were seen only in crabs ≥ 100 mm width. Testes and vasa deferentia of most males ≥ 150 mm were well to very well developed. No ripe ovaries were seen and no ovigerous individuals were taken in June. One berried female was observed in March.

The incidence of fouling organisms on crabs reflected the moulting history of the crabs. Sixty per cent of crabs in anecdysis and 14% of those in postecdysis were fouled. The predominant organism was the lepadid barnacle, Poecilasma inaequilaterale Pilsbry, which was attached to the gills in the branchial chamber.     

Nest structure and all stages of the long-cheeked yellow jacket Dolichovespula intermedia Birula (Hymenoptera: Vespidae)

Nest structure, morphology of all stages and behaviour have contributed to the phylogenetic and taxonomic studies of social vespids. Two aerial nests of Dolichovespula intermedia were discovered in China. The morphology of the three castes, the five larval instars, and the nest structure of D. intermedia Birula, are described in detail and illustrated. The presence of only one campaniform sensillum above each labial palp and the dense minute spicules on the posterior gena found in D. intermedia larvae are mentioned here for the first time for Dolichovespula. The identification characters between D. intermedia and Dolichovespula sylvestris are briefly discussed.