Crustacea Decapoda of the Paripe River Estuary, Pernambuco, Brazil

The Paripe river estuary is located in Itamaracá Island, north coast of Pernambuco, northeastern Brazil. Its Crustacea Decapoda fauna was studied during several years. In the estuary there are mangroves, mud- and sandbanks, and tidal creeks. The fauna comprises a total of 64 species in 20 families. The coexistence of these species confirms the ecological importance of this small estuary, only 1.6 km long and 0.5 km wide. The ecology of each species in the estuary is presented.     

A new species of glypheid lobster,Glyphea pisuergae (Crustacea,Glypheoidea), from the Early Jurassic of Palencia,Basque-Cantabrian Basin,Spain

A new glypheid lobster (Crustacea, Glypheidae), Glyphea pisuergae sp. nov. is described from the Early Jurassic (late Pliensbachian–early Toarcian) of Salinas de Pisuerga, Palencia, Spain. This species represents the second record for the genus in the Early Jurassic.     

PCR-Based Approach for Sequencing Mitochondrial Genomes of Decapod Crustaceans,with a Practical Example from Kuruma Prawn (<Emphasis Type="Italic">Marsupenaeus japonicus</Emphasis>)

An approach for sequencing the entire mitochondrial genomes (mitogenomes) of decapod crustaceans using 79 newly designed and 7 published polymerase chain reaction (PCR) primers is described. The approach comprises the following steps: (1) the entire mitogenome is amplified in 2 or 3 long PCRs; (2) the 86 primers are used in different combinations to amplify contiguous, overlapping short segments of the entire mitogenome with the diluted long PCR products as templates; (3) direct cycle sequencing is conducted using the short PCR products. This strategy allows a more rapid determination of decapod mitogenomic sequences than a traditional method using cloned mitochondrial DNA and primer walking strategy. As a practical example, the mitogenomic sequence for a kuruma prawn Marsupenaeus japonicus (Crustacea: Decapoda), was determined using the PCR-based approach.     

Morphological observations on the gills of dendrobranchiate shrimps

Gill morphology, traditionally, has played an important role in attempts to reconstruct the phylogenetic history of the Crustacea Decapoda. We examined the gills of dendrobranchiate shrimps (Crustacea, Decapoda, Dendrobranchiata) to test the assumption that all members of the clade have gills that are “dendrobranchiate” (highly branching) in form, from whence the taxon name Dendrobranchiata comes. Currently, the Dendrobranchiata consists of two superfamilies and seven families. Specimens from two genera in each of the known families were examined using light and scanning electron microscopy. Members of the family Luciferidae, all of which lack gills as adults, were not examined. Only one genus was examined for the Penaeidae (because they have been the subject of numerous previous studies) and Sicyoniidae (a monogeneric family). All gills examined have secondary branches that are further subdivided, conforming to existing and rather broad definitions of dendrobranchiate gills. Families with “typical” dendrobranchiate gills, which consist of curved secondary branches that in turn bear branched (dendritic) tubular tertiary elements on their distal surfaces, include the Penaeidae, Aristeidae, and Solenoceridae. In other families, secondary and tertiary gill elements are sometimes quite flattened, and the tertiary elements are not dendritic, giving the gill a distinctly non-dendrobranchiate appearance. Flattened biserial secondary branches and their flattened tertiary elements are particularly obvious in gills of the monogeneric family Sicyoniidae (Sicyonia). Within the family Sergestidae, gills of the genus Sergestes are unusual in having secondary branches that arise from the main gill axis in an alternating pattern; these gills also have distinctly oval tertiary elements that are not further subdivided and are directed basally rather than distally. Another sergestid genus, Petalidium, displays gills that differ from those of Sergestes; in Petalidium the secondary branches also come off the main gill axis in an alternating pattern, but these branches are more widely spaced and have relatively larger and broader tertiary elements when compared with gills of Sergestes. The family Benthesicyemidae also contains species with different gill types; Gennadas is shown to have flattened, plate-like tertiary elements, whereas Benthesicyemus has more typical dendrobranchiate gills. The significance of this variation in gill morphology within families and within the Dendrobranchiata as a whole is unclear at this point; rearrangements of the currently accepted phylogeny and resulting classification based solely on gill morphology are not recommended at this time.     

The larval crustacean dorsal organ and its relationship to the trilobite median tubercle

In the dorsal median anterior region of the head, the larvae of decapod Crustacea possess a discrete organ: a glandular-sensory complex which is not present in post-larval juvenile forms. Its external topography reveals the presence of one or two central pores (Brachyura, Anomura) or a poreless central area (Macrura) surrounded by four equidistant plate-pits which contain a central pimple or 'nipple'. The Macrura plate-pits lack the central pimple but develop a row of diminutive pegs. No definite function can yet be ascribed to the organ. The dorsal organ described here in Decapoda larvae closely resembles the median sensory tubercle found on the cephalon of some trilobites, especially Trinucleidae. In view of the possible homology between these structures in the two groups, previous interpretation of the trilobite organ as a median eye tubercle must be rejected.     

The phylogenetic position of the 'living fossils' Neoglyphea and Laurentaeglyphea (Decapoda: Glypheidea)

The Glypheidea is a group of lobster-like decapods that appeared in the Triassic and that was thought to be extinct until 1975, when a specimen of the species Neoglyphea inopinata was caught off the Philippines. More recently, in 2005, a specimen of another glypheid species, Laurentaeglyphea neocaledonica, was discovered near New Caledonia. Here, we construct a decapod molecular data set including the two extant glypheid species sequenced from eight nuclear and mitochondrial genes. Our study strongly shows that the two extant genera of glypheids cluster together, and further confirms the status of Glypheidea as a separate infraorder. Moreover the reptantian decapods are divided into two major groups, one including Brachyura, Anomura, and Axiidea, and the other including Astacidea, Polychelida, Achelata, and Glypheidea. Although commonly nicknamed 'Jurassic shrimps' and considered as 'living fossils', glypheids are therefore a derived decapod lineage.     

A parvo-like virus disease of penaeid shrimp

Cultured populations of four penaeid shrimp species (Crustacea, Decapoda) from four separate culture facilities in Asia were found to be adversely affected by a disease of presumed viral etiology. Individual shrimp with the disease displayed nonspecific signs, including poor growth rate, anorexia, reduced preening activity, increased surface fouling, and occasional opacity of tail musculature. These signs were accompanied by mortalities during the juvenile stages, after apparently normal development through the larval and postlarval stages. Accumulative mortality rates in epizootics in Penaeus merguiensis and P. semisulcatus reached as high as 50 to 100%, respectively, of the affected populations within 4 to 8 weeks of disease onset. The principal lesion, common to all four species, was necrosis and atrophy of the hepatopancreas, accompanied by the presence of large prominent basophilic, PAS-negative, Fuelgen-positive intranuclear inclusion bodies in affected hepatopancreatic tubule epithelial cells (hepatopancreatocytes). These inclusion bodies presumably developed from small, eosinophilic, intranuclear bodies that were also present in the affected tissues. Electron microscopy of affected hepatopancreatocytes revealed aggregations of 22- to 24-nm-diameter virus particles within the electron-dense granular inclusion body ground substance. The virus particle size and morphology, the close association of the nucleolus with the developing inclusion body, and the presence of intranuclear bodies within developing inclusion bodies are similar to cytopathological features reported for parvovirus infections in insects and vertebrates. It is suggested that this presumed virus disease of cultured penaeid shrimp be called HPV for Hepatopancreatic Parvo-like Virus disease.     

中国海鼓虾科阿莱鼓虾属分类研究(甲壳亚门,十足目)

阿莱鼓虾属 Arete Stimpson曾被多个研究者作为Athanas Leach角鼓虾属的异名处理(Banner and Banner,1960,1973;Chace,1988;Miya and Miyake,1968),作者认为Kemp(1915)描述Athanus polymorphus多形角鼓虾出现的第2胸足腕节4节为形态变异,第2胸足腕节分节情况完全可以将两属分开,阿莱鼓虾属应该做有效属处理.文中记述了中国海分布的3个种.borradailei,A.dorsdis,A.indicus,其中A.Borradailei为中国海首次报道.文中详细描述A.borradailei,并提供了世界阿莱鼓虾属种的检索表.所有研究标本保存在中国科学院海洋研究所.     

Mechanical functions of setae from the mouth apparatus of seven species of decapod crustaceans

The mouthpart setae of seven species of decapods were examined with macro-video recordings and scanning electron microscopy. The general mechanical (nonsensory) functions of the different mouthparts are described and an account of their setation is given. This offers the possibility to determine the mechanical functions of the different types of setae. Pappose setae do not participate in food handling but in general make setal barriers. Plumose setae likewise do not contact food objects but assist in current generation. Papposerrate setae are rare but they were seen to assist in pushing food particles into the mouth. Serrulate setae are very common and mainly participate in gentle food handling and grooming. Serrate setae are used for more rough food manipulation and grooming. The roughest shredding, tearing, and manipulation of prey items are handled by the cuspidate setae. Simple setae seem to be divided into two populations with very different functions. On the maxillipeds of Panulirus argus they are used for shredding, tearing, and holding the food objects, but on the basis of maxilla 2 of three other species they appear to have very little mechanical influence and only when handling small prey items. The functional scheme seems to be consistent within the Decapoda.     

On the influence of fishes on the evolution of benthic crustaceans

Though the interweavement of trophic chains in marine ecosystems of the past cannot be reconstructed, as the abundance, nutrition, reproductive rates and other aspects of the biology of fossil species are not known, it is possible to correlate trends in the evolution of single groups of animals, in the presented case the Crustacea, with the influence of other evolving organisms. The evolution of carnivorous, buoyant, well swimming modern fishes probably induced profound changes in marine ecosystems and influenced the evolution of crustaceans. Indications for these interactions are a. the absence or rare occurrence of defenseless archaic crustaceans in habitats, which are populated by teleostean fishes and the survival of some of these forms in refuges like caves and subterranean waters, and b. the reduction of the pleon in the course of the mesozoic evolution of the Decapoda, which occurs parallel to the radiation of the Teleostei, namely in the period between the early Jurassic and the Tertiary. The shortening of the pleon is interreted as a consequence of the stepwise change from a hyperbenthic to a more benthic Iife-stJe and the abandonment of the caridoid escape reaction. Other adaptations are also construed as results from the selective pressure produced by predators. Extant crustaceans which are able to coexist with fishes, among the macrozoobenthos especially the Decapoda and Peracarida, have a variety of protective adaptations, which help to reduce predation.     

中国海鼓虾科角鼓虾属分类研究(甲壳亚门,十足目)

对中国海鼓虾科角鼓虾属系统分类进行了研究.角鼓虾全世界共记录34种,其中中国海记录了9种.本文中记录中国海分布的角鼓虾属Athanas 8种,其中对中国海2新纪录种A.polymorphus Kemp和A.squillophilus Hayashi,进行了描记,并提供了中国角鼓虾种检索表.在中国的材料中:A.japonicus、A.ohsimai、A.polymorphus及A.squillophilus 4种的螯足表现了多态性,A.ohsimai和A.squillophilus的螯足多态性也是首次发现和记载.所有研究测量标本均保存在中国科学院海洋研究所.     

Report on some commensal pontoniinid shrimps (Crustacea: Palaemonidae) associated with an Indo-Pacific gorgonian host (Coelenterata: Gorgonacea)

The occurrence of two rare shrimps and a new species of the subfamily Pontoniinae (Crustacea, Decapoda, Natantia, Palaemonidae), previously considered to be free-living, in association with the gorgonian Mopsella eltisi Hickson is recorded. The new species is described and illustrated and some observations are made upon the morphology, size, distribution and systematics of the other species of shrimps. A key to the known species of the genus Hamodactylus is provided and the species of pontoniinid shrimps known to be associated with gorgonians are reviewed.     

Morphology of prezoea in the porcelain crab <Emphasis Type="Italic">Pachycheles stevensii</Emphasis> (Decapoda: Anomura: Porcellanidae) reared under laboratory conditions

Pachycheles stevensii Stimpson, 1858 is the only species of the family Porcellanidae (Decapoda, Anomura) living in the Russian waters of the Sea of Japan. The morphology of prezoeal larval stages of this crab obtained under laboratory conditions for the first time was studied and described in detail.Original Russian Text Copyright © 2005 by Biologiya Morya, Kornienko.     

First inventory of the Crustacea (Decapoda,Stomatopoda) of Juan de Nova Island with ecological observations and comparison with nearby islands in the Mozambique channel (Europa,Glorieuses, Mayotte)

Crustacea Decapoda and Stomatopoda are inventoried for the first time in Juan de Nova Island, Iles Eparses, Mozambique channel. In total, 112 species are reported: 69 crabs, 28 anomurans, 11 shrimps, 3 mantis shrimps and 1 lobster. A comparison is made with nearby islands in the Mozambique channel: Glorieuses Islands (157 species), Europa Island (178 species), and Mayotte Island (505 species). The lower species richness at Juan de Nova is explained by the small size of the island and by the difficulties to collect the crustaceans on the reef flat hardly accessible at low tide. The crustaceans are listed by main habitats from land to outer reef (2–20 m). The presence of the coconut crab (Birgus latro), an endangered species vulnerable to human predation, is confirmed.     

Brood care in freshwater crayfish and relationship with the offspring's sensory deficiencies

Prolonged brood care is one of the evolutionary clues for the successful colonization of freshwater habitats by freshwater crayfish (Astacida). By means of macrophotography, light microscopy, and scanning electron microscopy we investigated all phases of brood care in freshwater crayfish, with particular emphasis on the morphological structures involved. We selected the recently discovered parthenogenetic marbled crayfish (species identity not yet known) as a model organism due to its fast reproduction and high resistance to handling stress. In order to examine if there is a causal relationship between brood care and the developmental status of the offspring's sensory apparatus, we additionally investigated major sense organs of juvenile Stages 1-5 in comparison with those of the adults. Brood care in the marbled crayfish is characterized by initial and final "active" phases dominated by specific maternal or juvenile behavior and a medial "passive" phase based more on the action of temporarily developed structures rather than on behavior. The most remarkable feature of this period, which includes permanent carrying of the eggs and the first two juvenile stages under the mother's abdomen, is safeguarding of hatching by a telson thread that keeps the helpless newborn hatchlings linked to the egg cases on the maternal pleopods and thus prevents them from being lost. Further important transient structures are the recurved hooks on the first pereiopods of Stage 1 and 2 juveniles that are used to firmly attach these nonfeeding stages to the mother's abdomen. In hatchlings all sense organs necessary for an independent life, such as eyes, olfactory aesthetascs, gustatory fringed setae, hydrodynamic receptor hairs, and statocysts are not developed or are underdeveloped, making brood care indispensable. Most of these sense organs appear in Stage 2 juveniles, but only from Stage 3, the first freelancing and feeding stage, are all sense organs well developed and operating, thus reducing brood care in this final period to temporary provisioning of shelter. Brooding of the eggs and postembryonic brood care are to some extent also found in other freshwater Decapoda like freshwater crabs and aeglid anomurans, but safeguarding of hatching is confined to the Astacida only. This sophisticated mode of passive brood care is unique in the animal kingdom and is apparently related to the sensory deficiencies of the first juvenile stage.     

Diversity,biomass and production of decapod crustacean larvae in a changing environment

Summary

There is a latitudinal gradient in the species richness of Decapoda with pelagic larvae. For example, only two species of Brachyura are found around Svalbard, 54 species are known from the English Channel and ~100 from the Atlantic coast of the Iberian peninsula. The distributions of many species are limited by effects of temperature. Intermoult times of larvae are inversely related to temperature. In the field the size of larvae is inversely related to temperature, the relationship tending to increase in significance in successive larval stages. The timing of the seasonal occurrence of larvae of decapod species in the plankton is also related to temperature, to a greater extent than are seasonal cycles of the holoplankton. These effects of temperature on larval development influence the biomass and production of the larvae in the plankton. Some potential effects of climate change on the distributions and dynamics of planktonic larvae of decapods and consequent changes in their diversity, biomass and production can be predicted insofar as temperature is a limiting factor.     

A new classification of the branchiopod Crustacea

The first satisfactory groupings of the components of the Branchiopoda (Crustacea) were those of G. O. Sars, whose successive refinements, as modified by Caiman in a much used work, received wide acceptance. These schemes, and the more important of the subsequently suggested changes, are listed and tabulated. The Branchiopoda is a morphologically heterogeneous group whose component subgroups share a constellation of primitive features. It is also ancient, with representatives known from as far back as the Devonian, and probably originated in pre-Devonian times, yet still has many extant, sometimes highly successful, representatives. Such a situation presents difficulties to the would-be classifier. A new scheme is proposed which involves the elevation of four lower categories among the so-called Cladocera to ordinal rank. Two conchostracan taxa are also given ordinal status. The ten constituent orders now recognized within the Branchiopoda are defined in more detail than hitherto as a working basis for future investigations.     

A new Philocheras species (Decapoda,Crangonidae) from Hansa Bay,Papua New Guinea

A new species of crangonid shrimp, Philocheras wilkinsae (Decapoda, Crangonidae) is described from Hansa Bay, Madang Province, Papua New Guinea. The new species belongs to the japonicus group, and can be distinguished from the other members of this group by carapace dentition and carination. The pleopod structure is unique in the genus.     

A geographical survey of littoral crustacea in Norway and their use in paleolimnology

Littoral Crustacea from 400 sites all over Norway were related to lake pH, conductivity, altitude and major biogeography. Being tolerant animals, littoral Crustacea do not fall into clear pH classes as do many Bacillariophyceae or Chrysophyceae. Littoral Crustacea were subdivided into 4 main pH classes: acidobiontic, acidophilous, circumneutral and indifferent, the last group containing most species. Species typical for acidic lakes in the region were: A. excisa, S. serricaudatus, A. curvirostris, A. nana, S. mucronata and D. brachyurum; whereas D. longispina, S. vetulus, A. intermedia and A. rectangula were more common in circumneutral waters. Many littoral Crustacea were shown to be related to altitude, which should be considered in studies on lake histories. Some species showed in addition a restricted geographical distribution. Conductivity, with values recorded in this study, played a minor role in distribution of taxa. More ecological studies are necessary to fully utilize the potential of cladoceran remains in understanding lake histories.