Biting mechanism of the amphipod Anonyx (Crustacea: Amphipoda: Lysianassoidea)

Anonyx amphipods feed extensively on dead or weakened animals, often of large size. They cut off strips of food using the wide incisor processes of their mandibles like a pair of shears. The mandibles and associated mouthparts are specialized for this shearing action. The strips of food are coiled and packed into their proventriculi.     

Description and ecology of a spongicolous lysianassoid amphipod (Crustacea) from Antarctica

In the canals of three species of Antarctic Demospongiae, a new species of Lysianassoidea (Crustacea: Amphipoda) was found. The new species Pseudokoroga spongiophila is described, its ecology is briefly summarized. While the superfamily is represented in the Southern Ocean by 146 species, belonging to 54 genera, Pseudokoroga spongiophila n. sp. is one of the rare species symbiontically living in sponges. Up to 24 individuals were collected in 1000 cm³ of tissue of the host Demospongiae Jophon spatulatus (Kirkpatrick, 1907).     

A new superfamily,family, genus and species of marine amphipod,Protodulichia scandens,from Japan (Crustacea: Amphipoda: Senticaudata: Corophiida)

ABSTRACT

In this study, the new amphipod superfamily Protodulichioidea and family Protodulichiidae are established. Both belong to the infraorder Corophiida but is different from all known superfamilies and families. Amphipods included in the new superfamily and family are characterised by having a triangular head with large eyes, extremely long pereopod 7, and uropod 3 with a short peduncle and slender rami bearing a few robust setae. Protodulichia scandens gen. et sp. nov. is fully described here and its mast-building behaviour is also recorded.

urn:lsid:zoobank.org:pub:F6613B27-D954-4E4C-86CB-9FC5E9624334     

Biometry of brooding in seven species of amphipod (Crustacea) from the Clyde Sea area

Brood size was found to be correlated linearly with female body length in all species studied, except Ampelisca macrocephala, which is usually a single brooded species. Of the six multi-brooded species, Lembos websteri, Stegocephaloides christianiensis, Echinogammarus pirloti and Gammaropsis nitida produced small numbers of large eggs in the winter and large numbers of small eggs in the summer. In Bathyporeia pilosa larger numbers of smaller eggs were produced by the overwintering generation. In Corophium bonnellii, both maximum and minimum brood sizes were produced by the summer generation. The largest broods relative to female body size were produced by the smaller species. In L. websteri, C. bonnellii and B. pilosa mean female size was smaller in the summer than the winter generation.     

Observations on zygopine weevil behaviour (Coleoptera: Curculionidae: Zygopinae)

Observations on the behaviour and chosen environment are reported of the zygopine weevils Mecopus audinetii, M. bispinosus, M. fausti, M. pulvereus, Phylaitis v-alba and Osphilia sp. Mecopus audinetii and M. bispinosus were not distinguished in the field, but can be separated by details of the male and female genitalia and by the presence in the male of M. bispinosus of long black hairs on the pronotum. All the species studied were found on the bark of fallen or dying trees, the Mecopus species and Phylaitis v-alba being associated with whitish-silvery bark and the Osphilia species with greenish-brown substrates. The small Phylaitis species was found on branches of smaller diameter than those frequented by the larger Mecopus species. All the species are fairly cryptic in coloration, but when moving the larger species are more visible than the smaller, and the ones on pale bark are more visible than those on greenish-brown bark. Potential predators may be confused by jerky movement patterns observed in all species and the distant shadows cast by the long-legged larger Mecopus. The weevils are not believed to be involved in any mimicry, although this has been suggested for other members of the same subfamily. A single contest between males of Mecopus audinetii/bispinosus was observed, in the absence of a female. Each male attempted to dislodge its opponent from the substrate using its rostrum; the thoracic spines were not seen to be used. Contests between males of Osphilia sp. and Phylaitis v-alba were observed in the presence of females of the appropriate species. The males of Osphilia species attempted to dislodge one another from the back of the female in contention, and also engaged in a spiralling flight together. The males of Phylaitis v-alba did not come into physical contact, but responded to the threat of an approach. During copulation in Mecopus audinetii/bispinosus and Osphilia sp. the male repeatedly brushed the head and thorax of the female with his front legs. In the first species the male stood on the substrate and ‘caged’ the female with his legs and rostrum but in the second the male, ‘rode’ the female. Both species oviposit into the bark of their trees, the females using the rostrum to drill a hole for the ovipositor. The length of the rostrum probably determines the thickness of the bark through which eggs are laid, and hence the area of the region of the tree inhabited by the beetles.     

Apodidymochelia,a new genus of gammaridean amphipod from the tropical Atlantic Ocean (Crustacea: Amphipoda: Didymochellidae)

Apodidymochelia castellata, new genus, new species is the second genus and fourth species in the rare and poorly known family Didymocheliidae. Apodidymochelia is separated from Didymochelia primarily on mandible structure. This record extends the known range of the family into the Atlantic Ocean.     

Observations on the behaviour of the Cape girdled lizard Cordylus cordylus (Reptilia: Cordylidae)

Cape girdled lizards Cordylus cordylus are social and territorial. Behaviour observed in captivity revealed at least 24 distinct postures and displays. Thermoregulatory behaviour was the most frequent of all behaviours observed (66·7%). Of the social behaviours, aggression was observed most frequently (72·1%). Six behavioural postures are not known to have been described before. This species has no bright colours or contrasting markings to use in displays to conspecifics.     

The marine fauna and flora of the Isles of Scilly. Tanaidacea (Crustacea: Peracarida)

Records of Tanaidacea from the Isles of Scilly are collated; the published literature is reviewed, together with unpublished records from various sources. These data are supplemented by recent material collected in the archipelago between 2001 and 2010. A total of 10 species are now known from littoral and sublittoral habitats of the Isles. These records include the first published record for the British Isles of the tanaid Zeuxo holdichi, the known distribution of which is summarized. The apseudomorph Apseudopsis latreilli is common to abundant on littoral sandflats but Apseudes talpa generally replaces this species on more heterogeneous substrata and sublittorally. Tanais dulongii and Leptochelia savignyi are present throughout the archipelago among littoral algal-turf with embedded sediment. Zoogeographically, the list includes species from the temperate–boreal and, mainly, from Lusitanian waters.     

Natural history of the terrestrial amphipod Cerrorchestia hyloraina Lindeman (Crustacea: Amphipoda; Talitridae) in a Costa Rican cloud forest

The field biology of the Costa Rican landhopper (Crustacea: Amphipoda: Talitridae) Cerrorchestia hyloraina Lindeman was investigated in the Monteverde Cloud Forest Reserve, Costa Rica. On the Pacific (leeward) side of the continental divide, local distribution follows a gradient of moisture, from densities of over 200 m^-2 in the elfin forest at 1600 m, to extremely low densities in drier forest types. Below 1400 m, the leaf litter is apparently too dry to support landhopper populations. On the Caribbean (windward) side of the continental divide, landhoppers occur well below 1400 m. A discussion of geographic distribution is included. Landhoppers prefer aged (microfaunally pre-processed) leaves as food, and move about only at night or in the mornings of heavily overcast days. Average female fecundity is seven eggs, with progressive loss of marsupium contents over time. The sex ratio is biased towards females. In cloud forest, breeding apparently is continuous throughout the year, with some increase after the beginning of the rainy season. There are 9–10 juvenile instars and 5–6 adult instars. The relationship of antennal segment number to total body length is linear.     

A new species of amphipod of the genus Neomegamphopus (Crustacea,Amphipoda, Neomegamphopidae) from Rodrigues,Indian Ocean

A new species of Neomegamphopus Shoemaker is described from Rodrigues, Indian Ocean. The systematics of the Neomegamphopidae from the Indian Ocean is discussed and a key to the species from that ocean is provided.     

The occurrence,mechanics and significance of burying behaviour in crabs (Crustacea: Brachyura)

Although the terms burrowing and burying are often used interchangeably in the literature, there are clear distinctions between these two types of behaviour in terms of their ecological, mechanical and physiological implications. Both types of behaviour are widely observed in the Brachyura. In comparison to the well researched area of burrowing in crabs, information on burying is relatively dispersed. This review will examine the extent of burying behaviour in brachyurans, and the physiological and ecological consequences of the behaviour within the group. At least nine of the 50 families of brachyuran crabs have either been observed to bury in soft substrata or are suspected, on morphological grounds, of burying. There appears to be no specific morphological adaptations for burying in brachyurans, apart from those features associated with respiration whilst buried in the sediment. Buried individuals must ensure constant access to oxygenated water in the face of mechanical problems resulting from direct contact with the sediment, i.e., the threat of clogging. Burying taxa deal with this challenge through accessory respiratory channels and altered respiratory rhythms. The evolutionary implication of the burying habit is equivocal. Burying taxa are amongst the most speciose and numerically dominant brachyuran groups in marine systems, all reaching their greatest diversity and abundance in soft substrata. Burying may be an ancestral condition, with many of these groups evolving in habitats characterized by soft sediment.     

Observations on the nesting behaviour of seven species of Crabro (Hymenoptera,Sphecidae)

Summary

Data are presented on the nests and prey of seven species of Crabro from diverse localities in North America. In two instances (virgatus and largior) this is the first published report. Further information is provided for the following previously studied species: argusinus, advena, cribrellifer, latipes, and monticola. Behavioural differences among these species are not conspicuous. Most are rather general fly predators, but cribrellifer appears to show a strong preference for Asilidae. There are also differences in type of soil used for nesting and in antipredator behaviour such as approach flights and daily cycles of activity. Two species, largior and monticola, provision their nests early in the morning, before miltogrammine flies are active in numbers. All species probably make cells of two sizes, larger cells containing more prey and producing females, smaller cells males.