A revision of the Caridina serrata species group,with descriptions of five new species (Crustacea: Decapoda: Caridea: Atyidae)

The taxonomy of the Caridina serrata species group (Caridea: Atyidae) is revised. Neotypes of C. serrata Stimpson, 1860, and C. cantonensis Yu, 1938, are designated. Additional information on Caridina sphyrapoda Liang and Zhou, 1993 is provided. Five new species of the Caridina serrata species group are described, namely Caridina nanaoensis from Guangdong Province, C. apodosis from Hong Kong, and C. yulinica, C. wumingensis and C. mutata from Guangxi Province, all in southern China. A key to all members of the species group is included.     

On the correct name for Hemigrapsus edwardsii (Hilgendorf, 1882) (Brachyura: Varunidae) from New Zealand

The specific name for the New Zealand crab long known as Hemigrapsus edwardsii (Hilgendorf, 1882) has been uncertain because of problems with generic definitions. Resolving this question required examination of the relationships between Brachynotus de Haan, 1835, Heterograpsus Lucas 1849 and Hemigrapsus Dana, 1851. The genus Heterograpsus is an objective junior synonym of Brachynotus since they both have the same type species, Gonoplax sexdentatus Risso, 1827. Comparison of Brachynotus and Hemigrapsus shows that the New Zealand species belongs in Hemigrapsus and should be known as H. sexdentatus (H. Milne Edwards, 1837).     

Juvenile development and growth patterns in the mud crab Eurytium limosum (Say, 1818) (Decapoda,Brachyura, Xanthidae) under laboratory conditions

The post‐larval development of the mud crab Eurytium limosum was studied under laboratory conditions by using the offspring of ovigerous females collected at the Comprido River mangrove, SP, Brazil. The first crab stage is fully described and the juvenile development, until crab stage 10, is examined with emphasis on morphological change, sexual differentiation and growth patterns. The carapace of the first crab stage is nearly square as observed in other xanthids, becoming similar to adults only at stage 15. The sexes can be distinguished from stage four, based on the number of pleopods and their morphology. While the intermoult period increases, the moult percentage decreases at each stage. The abdominal allometric growth is sex‐dependent, with males showing a negative (b?=?0.71) and females an isometric (b?=?0.95) relative growth pattern. Male gonopods undergo a positive allometric growth, and their shape changes remarkably until sexual maturity. The cheliped dentition can be observed after stage 4. Regardless of sex, most crabs have a molariform right cheliped, which is thought to aid the handling of asymmetric prey such as gastropods.     

A review of the north-western Pacific species of the genus Paguristes (Decapoda: Anomura: Diogenidae), I. Five species initially reported by Ortmann (1892) from Japan

Five species of the hermit crab genus Paguristes Dana, 1851, initially reported by Ortmann (1892) from Japan, are revised based on the materials reported by Ortmann (1892), Doflein (1902), Balss (1913) and Miyake (1978), and on newly collected specimens. The specific status of P. palythophilus Ortmann, 1892, is clarified, and a species confused with P. palythophilus is described as new, P. albimaculatus. It has been revealed that P. kagoshimensis Ortmann, 1892, is actually a junior subjective synonym of P. digitalis Stimpson, 1858. The species heretofore assigned to P. kagoshimensis is described as new, P. versus. It has been confirmed that Paguristes acanthomerus Ortmann, 1892, is a valid species and that P. barbatus sensu Ortmann, 1892, is the same species as P. ortmanni Miyake, 1978. Further, a new species, P. doederleini, is described for P. setosus sensu Ortmann, 1892. It is also shown that a part of the group of specimens identified as Paguristes puniceus by Miyake (1978) is referable to P. doederleini. In addition to the three new species recognized herein, the four previously described species are also redescribed in detail in order to make clear their taxonomic status.     

The sentinel crabs of the genus Chaenostoma (Stimpson, 1858) (Crustacea: Brachyura: Macrophthalmidae), with description of a new species and new records

The genus Chaenostoma (Stimpson, 1858) so far includes four distinct species, i.e. C. boscii (Audouin, 1826), C. lisae (Poupin and Bouchard, 2010), C. punctulatus Miers, 1884, and C. sinuspersici (Naderloo and Türkay, 2011). Chaenostoma java n. sp. is here described as a fifth species from Java (Indonesia) easily distinguished from its congeners by the features of the male first pleopod, the penultimate segment of the male abdomen, and the unique female gonopore. The new species is most similar to C. lisae, but they differ in the morphology of the male chelipeds and female gonopores. Chaenostoma lisae is redescribed and recorded from Madagascar, Mayotte I. and New Caledonia. An identification key for the genus is provided.     

Larval development of Pandalus gracilis Stimpson (Crustacea: Decapoda: Pandalidae) reared in the laboratory

The complete larval development of Pandalus gracilis Stimpson is described based on larvae reared in the laboratory. The species has four larval stages (stages 1–4) and one postlarval stage (stage 5). The survival rate of the postlarva stage is very high. Of the 40 larvae reared individually, 39 larvae moulted to the postlarva stage within approximately 21 days at a rearing temperature of 15°C. Larval morphological characteristics of the species are described and figured. Larval development of P. gracilis is compared with other Pandalus and Pandalopsis species. Komai (1999 Komai, T. 1999. A revision of the genus Pandalus (Crustacea: Decapoda: Caridea: Pandalidae).. Journal of Natural History, 33: 1256–1372.  [Google Scholar]) divided species of Pandalus into four species groups based on adult morphology. Pandalus gracilis belongs to the P. hypsinotus group. In this study, using larval characters, the P. hypsinotus group can be divided into two groups by the appearance of the mandibular palp and the shape of the telson: the first group contains P. hypsinotus and P. danae, and the second group contains P. gracilis, P. prensor, and P. nipponensis.     

Larval development of Clibanarius antillensis Stimpson, 1859 (Crustacea: Anomura: Diogenidae) reared under laboratory conditions: a comparison between Panamanian and Brazilian populations

The larval developmental sequences of Clibanarius antillensis Stimpson from first zoea through to megalopa are compared between laboratory-reared populations from Panama and Brazil. Only four zoeal stages are recorded for the Panamanian population, in contrast to four or five for the Brazilian larvae. Other differences in morphology are discussed and illustrated. Variations resulting from geographic differences and/or differing laboratory conditions raise the question of the validity of phylogenetic hypotheses based on single laboratory rearing events.     

Host ranges of parasitoids (Hymenoptera: Braconidae and Ichneumonidae) reared from Epermenia chaerophyllella (Goeze) (Lepidoptera: Epermeniidae) in Britain,with description of a new species of Triclistus (Ichneumonidae)

The complex of parasitoids attacking larval stages of Epermenia chaerophyllella in Britain is outlined, and the host range of each of the species recorded (three braconids and four ichneumonids) is discussed. ‘Ecological’ factors, such as the behavioural similarity of unrelated hosts during the vulnerable parts of their life histories, seem to have been important in the evolution of the host associations of several of these parasitoids, even though they are koinobionts. A new species, Triclistus epermeniae Shaw and Aeschlimann, is described.