@inbook {950, title = {Crustacea}, booktitle = {Fauna Japonica sive Descriptio Animalium, quae in Itinere per Japoniam, Jussu et Auspiciis Superiorum, qui Summum in India Batava Imperium Tenent, Suscepto, Annis 1823{\textendash}1830 Collegit, Notis, Observationibus et Adumbrationibus Illustravit}, year = {1844}, pages = {1-243}, publisher = {Lugduni-Batavorum}, organization = {Lugduni-Batavorum}, address = {Leiden}, author = {de Haan, W.}, editor = {von Siebold, P.F.} } @article {282, title = {Synalpheus shrimps (Crustacea: Decapoda: Alpheidae). I. The Gambarelloides group, with a description of a new species}, journal = {Memoires of the Hourglass Cruises}, volume = {7}, number = {2}, year = {1984}, pages = {1-125}, author = {Dardeau, M.R.} } @article {366, title = {Host use patterns and demography in a guild of tropical sponge-dwelling shrimps}, journal = {Marine Ecology-Progress Series}, volume = {90}, number = {2}, year = {1992}, note = {USA1992English}, pages = {127-138}, abstract = {Demographic consequences of the commensal lifestyle of shrimps Synalpheus spp. were assessed by sampling sponges and coral rubble on reefs in Caribbean Panama. Eight of 22 species were found solely or primarily within the internal canals of sponges. Among these sponge-dwellers, host specificity ranged from generation (occurrence in gtoreq 4 host species) to specialization on a single host species, and sponges used in the field were also preferreed in laboratory choice assays. Living in sponges had important consequences for shrimp populations. Parasitism by epicaridean isopods averaged 6 times higher in obligate sponge-dwellers (17\%) than in free-living species (2.5\%). Sponge species differed in the mean size and size range of habitable spaces they provide, number of potentially competing Synalpheus species they support, and vulnerability of associated shrimps to parasitism. Similarly, conspecific shrimp populations occupying different hosts differed demographically. Specifically, populations and Synalpheus brooksi in the sponge Spheciospongia vesparium were significantly less dense, less parasitized, had larger body sizes, and tended toward higher proportions of mature females than conspecifics in the co-occurring sponge Agelas clathrodes. High host specificity, regional variation in host use, and demographic and genetic differentiation among conspecific shrimps in different host species suggest that the commensal lifestyle has pervasive, and potentially evolutionarily important, consequences for the population biology of this diverse group of shrimps.}, keywords = {Agelas clathrodes (Porifera), Animalia, animals, Arthropoda, Arthropods, Comparative and Experimental Morphology, Crustaceans, Ecology, Ecology (Environmental Sciences), Environmental Biology/Animal [07508], Environmental Biology/Oceanography [07512], Environmental Sciences), Evolution [01500], Evolution and Adaptation, Genetics, Genetics and Cytogenetics/Animal [03506], Genetics and Cytogenetics/Population Genetics (1972- ) [03509], Invertebrata, Invertebrates, Malacostraca: Crustacea, Marine Ecology (Ecology, Neotropical region), Panama (Central America, Physiology, Physiology and Pathology/Arthropoda-Crustacea [64054], Physiology and Pathology/Porifera [64006], Population Genetics (Population Studies), Porifera [39000], Porifera: Invertebrata, Spheciospongia vesparium (Organisms - Unspecified), sponge (Porifera), Synalpheus brooksi (Malacostraca), Synalpheus spp. (Malacostraca)}, author = {Duffy, J. E.} } @article {329, title = {Phylogenetic evidence for an ancient rapid radiation of Caribbean sponge-dwelling snapping shrimps (Synalpheus)}, journal = {Molecular Phylogenetics \& Evolution}, volume = {30}, number = {3}, year = {2004}, note = {Article.1055-7903 (ISSN print)English}, month = {March}, pages = {563-581}, abstract = {A common challenge in reconstructing phylogenies involves a high frequency of short internal branches, which makes basal relationships difficult to resolve. Often it is not clear whether this pattern results from insufficient or inappropriate data, versus from a rapid evolutionary radiation. The snapping shrimp genus Synalpheus, which contains in excess of 100 species and is a prominent component of coral-reef faunas worldwide, provides an example. Its taxonomy has long been problematic due to the subtlety of diagnostic characters and apparently widespread variability within species. Here we use partial mt COI and 16S rRNA sequences and morphological characters to reconstruct relationships among 31 species in the morphologically well-defined gambarelloides species group, a putative clade of obligate sponge associates that is mostly endemic to the Caribbean and contains the only known eusocial marine animals. Analysis of the combined data produced a single tree with good support for many terminal clades and for relationships with outgroups, but poor support for branches near the base of the gambarelloides group. Most basal branches are extremely short and terminal branches are long, suggesting a relatively ancient, but rapid radiation of the gambarelloides group. This hypothesis is supported by significant departure from a null model of temporally random cladogenesis. Calibration of divergence times among gambarelloides-group species using data from three geminate pairs of Synalpheus species separated by the isthmus of Panama suggests a major radiation between apprx5 and 7 Mya, a few My before final closure of the Panamanian seaway during a period of spreading carbonate environments in the Caribbean; a second, smaller radiation occurred apprx4 Mya. This molecular evidence for a rapid radiation among Caribbean marine organisms in the late Miocene/early Pliocene is strikingly similar to patterns documented from fossil data for several other Caribbean reef-associated invertebrate taxa. The similar patterns and timing of cladogenesis evidenced by molecular and fossil data for different Caribbean and East Pacific taxa suggests that the radiation involved a wide range of organisms, and strengthens the case that poor basal resolution in the gambarelloides group of Synalpheus reflects a real evolutionary phenomenon. The rapid radiation also helps explain the historical difficulty of diagnosing species in Synalpheus.}, keywords = {16S rRNA sequences, adaptive radiation}, author = {Morrison, C. L. and Rios, R. and Duffy, J. E.} } @article {402, title = {Coordinated group response to nest intruders in social shrimp}, journal = {Biology Letters}, volume = {1}, number = {1}, year = {2005}, note = {1744-9561}, month = {Mar}, pages = {49-52}, abstract = {A key characteristic of highly social animals is collective group response to important stimuli such as invasion by enemies. The marine societies of social snapping shrimp share many convergences with terrestrial eusocial animals, including aggressive reaction to strangers, but no group actions have yet been observed in shrimp. Here we describe {\textquoteright}coordinated snapping{\textquoteright}, during which a sentinel shrimp reacts to danger by recruiting other colony members to snap in concert for several to tens of seconds. This distinctive behaviour is a specific response to intrusion by strange shrimp into the colony{\textquoteright}s sponge and is highly successful at repelling these intruders. Although coordinated snapping apparently functions analogously to alarm responses in other social animals, colony members in social shrimp do not rush to the site of the attack. Coordinated snapping appears instead to be a warning signal to would-be intruders that the sponge is occupied by a cooperative colony ready to defend it. This is the first evidence for coordinated communication in social shrimp and represents yet another remarkable convergence between social shrimp, insects and vertebrates.}, url = {://000232135300013}, author = {Toth, E. and Duffy, J. E.} } @article {369, title = {Gonopore sexing technique allows determination of sex ratios and helper composition in eusocial shrimps}, journal = {Marine Biology}, volume = {151}, number = {5}, year = {2007}, note = {0025-3162}, month = {Jun}, pages = {1875-1886}, abstract = {An evaluation of the social organization and sexual system of eusocial species of Synalpheus has been hindered because it has not been possible to determine the sexual composition of colony helpers (workers). The external sexual characters typically used to sex caridean shrimps are lacking in Synalpheus. We used SEM sexing technique to determine the sexual composition of helpers in colonies of Synalpheus regalis, S. rathbunae, S. chacei, S. rathbunae A (see Morrison et al. Mol Phylogen Evol 30:563-568, 2004), and S. filidigitus. Colonies consisted of both sexes and sex ratios of helpers generally conformed to 50:50 female to male. Females were characterized by gonopores with U-shaped slits on the coxae of the third pereopods (first walking legs) while males had oval gonopore openings on the coxae of the fifth pereopods (third or last walking legs). In S. chacei, S. filidigitus, and S. rathbunae A, a few helpers were found that had both male and female gonopores (intersexes). All three reproductive females (queens) of S. filidigitus examined were intersexes. Sexing of helpers allowed us to test some hypotheses about sexual differences in helper morphology that might indicate task specialization (division of labor). Male helpers were not different from female ones in body size (except in S. regalis: males somewhat larger) and in fighting chela size. The lack of sexual dimorphism in these characters suggests no male-female specialization in colony tasks such as defense. The presence of male and female helpers similar in size suggests that the sexual system of these eusocial species is gonochoristic, although protandry of some sort in S. filidigitus can not be ruled out. The intersexuality observed in a few individuals may be due to developmental anomalies, protandry, or even simultaneous hermaphroditism. Finally, the sexing technique allowed us to establish that new colonizers of unoccupied sponges in S. rathbunae are a single male and female of helper size.}, url = {://000246614300025}, author = {Toth, E. and Bauer, R. T.} }