TL;DR: It is intended in these studies of the Plymouth Brachyura to rear as many species as possible from the berried crab, and thus to ascertain without doubt the larvae of each species in all stages, so that they may be recognisable in the plankton.
Abstract: It is difficult to rear crabs from the egg, and few experiments of the kind have been successful. It is intended in these studies of the Plymouth Brachyura to rear as many species as possible from the berried crab, and thus to ascertain without doubt the larvae of each species in all stages, so that they may be recognisable in the plankton.The members of the Oxyrhyncha so far observed in the Plymouth district are the following:-Inachus Dorsettensis (Pennant), Inachus Dorynchus Leach, Macropodia longirostris (Fabricius), Macropodia Egyptia A. Milne-Edwards, Macropodia rostratus (L.), Achaeus Cranchii Leach, Maia squinado (Herbst), Pisa biaculeata (Montagu), Hyas araneus (L.), Hyas coarcticus Leach, Eurynome aspera (Pennant).
TL;DR: Results demonstrate that at least some decorator crabs actively choose certain algae for decoration and these choices are not necessarily related to feeding preferences, which might be important for crabs like these, which live in areas where omnivorous fishes are the main algal grazers and predators.
TL;DR: Records of several rare or interesting Crustacea Decapoda from the Azores are presented, and Azorean Portunus hastatus prove to be much less pubescent than their Mediterranean counterparts, and detailed drawings are given for this common but rarely comprehensively illustrated species.
Abstract: Records of several rare or interesting Crustacea Decapoda from the Azores are presented in the present paper. Periclimenes sagittifer and Athanas nitescens are recorded for the first time in the archipelago. Periclimenes sagittifer was found on various hydroids and the antipatharian Antipathes wollastoni, some juveniles being also found amongst algae. Athanas nitescens was encountered free-living and in a shell inhabited by the hermit crab Dardanus calidus. Comparative illustrations are given for Azorean Periclimenes sagittifer and French specimens. New characters are proposed to distinguish Eualus cranchii, E. drachi, E. occultus and E. pusiolus, and a key to Northeastern Atlantic and Mediterranean Eualus species is provided. Azorean specimens of Hippolyte varians prove to be especially small and slender, whilst Azorean Stenopus spinosus may have red, white or even proximally red and distally white antennae. The association between the hermit crab Nematopagurus longicornis and the antipatharian Antipathes wollastoni is recorded for the first time. A possibly undescribed Macropodia species is here recorded and illustrated as Macropodia sp., as only juvenile and damaged adult specimens were found. Azorean Portunus hastatus prove to be much less pubescent than their Mediterranean counterparts, and detailed drawings are given for this common but rarely comprehensively illustrated species.
TL;DR: Spermatozoal ultrastructure does not support a majoid-hymenosomatid relationship and is equivocal with regard to the placement of Cryptochiridae in either the Thoracotremata or Heterotremeata, the prominent operculum strongly differentiates cryptochirids from Majoidea.
Abstract: Comparative ultrastructure of majoid spermatozoa belonging to 23 species, in 19 genera and five families, is considered, with new data on Schizophrys aspera; S. rufescens (Majidae, Majinae); Camposcia retusa (Inachidae); Pyromaia tuberculata (Inachoididae); and Huenia heraldica and Menaethius monoceros (Epialtidae, Epialtinae). The oregoniid Chionoecetes opilio, and inachids Cyrtomaia furici, Platymaia rebierei, Macropodia longirostris and Inachus phalangium, possibly with Camposcia retusa, but not Podochela riisei, appear to form a group. Within the inachids, Macropodia and Inachus are especially close. A domed central acrosome zone, seen in most inachid sperm, in majines (both Schizophrys species), in pisines (Oxypleurodon orbiculatus and O. stuckiae) and epialtines (Huenia heraldica and Menaethius monoceros), appears to be an autapomorphy of these majoids. A peripheral acrosome zone is seen in the inachid Grypacheus hyalinus, two inachoidids (P. tuberculata and Stenorhynchus seticornis) and the majid Maja squinado. Pyromaia tuberculata differs from other inachoidids in having a slightly dome-shaped operculum. The mithracine Macrocoeloma trispinosum (Majidae) sperm more closely resembles Inachoididae, than Inachidae. Spermatologically, the family Majidae and the subfamily Majinae are not homogeneous. Spermatozoal ultrastructure does not support a majoid-hymenosomatid relationship and is equivocal with regard to the placement of Cryptochiridae in either the Thoracotremata or Heterotremata, the prominent operculum strongly differentiates cryptochirids from Majoidea. Acta Zoologica
TL;DR: The present paper deals with decapod crustaceans, collected during "Aurelia"-cruises, which are considered to be scarce or rare in the southern North Sea, completed with data from bottom-samples and other sources.
Abstract: INTRODUCTION Since April 1972 an ecological trawl-survey programme has been undertaken by the Netherlands Institute for Sea Research (NIOZ), Texel, in the southern North Sea with the R. V. "Aurelia". The main object is to obtain information on distribution, density, biomass and fluctuations of crawling or swimming demersal (epibenthic) fauna such as small fishes, shrimps, prawns, crabs, asteroids, ophiuroids and some gastropods, for the evaluation of the role of these carnivores in the benthic ecosystem of the southern North Sea. Sedimentological aspects of the area are described by Creutzberg & Postma (1979). Within the context of the present paper the most important feature is the mesh of 5 x 5 mm2 of the cod end of the 51/2 m beam-trawl used and the extensive area of 5000-10,000 m2 covered during each haul. These exceptional circumstances resulted into faunistically interesting catches which gave rise to a cooperation with taxonomic specialists of the Rijksmuseum van Natuurlijke Historie (RMNH), Leiden. The present paper deals with decapod crustaceans, collected during "Aurelia"-cruises, which are considered to be scarce or rare in the southern North Sea, completed with data from bottom-samples and other sources. The species in question are: Pandalina brevirostris, Spirontocaris lilljeborgii, Alpheus macrocheles, Pontophilus spinosus, Pontophilus bispinosus, Galathea dispersa, Ebalia tuberosa, Ebalia tumefacta, Ebalia cranchii, Atelecyclus rotundatus, Monodaeus couchii, Callianassa subterranea, Callianassa tyrrhena, Upogeb ia stellata and Upogebia deltaura. Of the genus Macropodia a number of specimens have been collected, which partly were identified as M. linaresi. Other specimens, however, represent one or two new species. On Macropodia in the southern North Sea a seperate paper will