First record and evidence of an established population of the North American mud crab Dyspanopeus sayi (Brachyura: Heterotremata: Panopeidae) in the western Mediterranean

The panopeid crab Dyspanopeus sayi (Smith, 1869) is reported here from the Ebro Delta (Mediterranean coast of the Iberian Peninsula). Originally endemic to the Atlantic coast of North America, D. sayi was involuntarily introduced into Britain, France and the Netherlands, and into the Adriatic and Black Sea within the last thirty years. Here we provide the first record of this species from the western Mediterranean Sea. Occurrences of ovigerous females at different localities of the delta and in different years provide evidence that the population is well established. Mitochondrial DNA confirms the identity of the species and indicates that the introduced population consists of at least three female lineages. The first zoeal stage of D. sayi was obtained in the laboratory from an ovigerous female captured in August 2010 with embryos in an advanced stage of development. The morphology of the zoea I is described here in detail and is similar to the one previously reported for native populations.Travel funds to CDS and students were made possible through an exchange program of the DAAD (D/03/40344) and the Spanish Ministerio de Ciencia y Tecnología – Acciones Integradas (HA2003-078), with José A. Cuesta as Spanish collaborator. Florian Gmeiner, Silke Reuschel and Lapo Ragionieri assisted during field collections in 2005 and 2006 respectively and students at the University of Regensburg helped with the molecular work. Financial support to GG (post-doctoral fellowship; INIA) was provided by the Ministry of Science and Research. The authors would like to thank Agustí Benito, fisherman of Sant Carles de la Ràpita for his collaboration in catching crabs. PA acknowledges research project CGL2009-12912-C03-03 from the Ministerio de Ciencia e Innovación (Spain). Paul Clark kindly made available important literature and shared his own unpublished description of the first zoeal stage of Dyspanopeus sayi.info:eu-repo/semantics/publishedVersio

Marine biogeographic boundaries and human introduction along the European coast revealed by phylogeography of the prawn Palaemon elegans

11 páginas, 5 figuras, 6 tablas.A phylogeographic analysis is carried out for the widely distributed European littoral prawn Palaemon elegans in order to test for potential genetic differentiation and geographic structure. Mitochondrial sequences were obtained from 283 specimens from the northeastern Atlantic, the Baltic, Mediterranean, Black and Caspian Seas. Our study revealed a surprisingly complex population structure. Three main haplogroups can be separated: one from the Atlantic (Type I) and two from the Mediterranean (Types II and III). While the Mediterranean types occur in sympatry, a clear phylogeographic break was observed along the Almería-Oran Front separating Type I and giving evidence for a genetic isolation of Atlantic and Mediterranean populations. Type III represents the most distinct haplogroup with high levels of nucleotide divergence, indicating the occurrence of a cryptic species with a Messinian origin. The colonization of the southeastern Baltic Sea is most likely due to human introduction.For financial support we like to thank the European Union funding (FEDER), the Spanish “Ministerio de Educación y Ciencia, Plan Nacional I+D” (Project CGL2004-01083), the DAAD (D/03/40344) and the Spanish “Ministerio de Ciencia y Tecnología—Acciones Integradas (HA2003-078).Peer reviewe

A new genus and species of tree-climbing crab (Crustacea: Brachyura: Sesarmidae) from Taiwan with notes on its ecology and larval morphology

11 páginas, 8 figuras.A new genus and species of sesarmid crab, Scandarma lintou, is described from Taiwan. This crab has a semi-terrestrial habit: adults and juveniles thrive in ind-protected and vegetated habitats in close vicinity of fresh water and up to one kilometer from the sea. In southern Taiwan, this species was most commonly found hiding in leaf axils or climbing on the thorny leaves of the screw pine Pandanus odoratissimus Linnaeus. During the reproductive season (June to January), ovigerous females migrate to estuaries, where small and free-swimming pelagic larvae are released into the brackish waters and probably washed into the sea. Morphologically, this species is superficially similar to species of other semi-terrestrial sesarmid genera, but differs from these taxa by the shape of the anterolateral carapace region, by the markedly flattened fingers, by the presence of a row of tubercles on the dorsal border of the dactylus, a row of ventral spines on the pollex, and a granular ridge on the dorsal face of the palm. The first zoeal stage of the new genus shows two autapomorphies in the morphology of antennae and first maxillipeds. Otherwise, this stage presents the combination of features that are typical of sesarmid zoeae, i.e. absence of lateral carapace spines, a 2,3 setation of the maxillar endopod, a 2,2,3,3 setation on the basis of the first maxilliped, and a characteristic setation pattern of antennae and telson.Peer reviewe

When Indian crabs were not yet Asian - biogeographic evidence for Eocene proximity of India and Southeast Asia

Background: The faunal and floral relationship of northward-drifting India with its neighboring continents is of general biogeographic interest as an important driver of regional biodiversity. However, direct biogeographic connectivity of India and Southeast Asia during the Cenozoic remains largely unexplored. We investigate timing, direction and mechanisms of faunal exchange between India and Southeast Asia, based on a molecular phylogeny, molecular clock-derived time estimates and biogeographic reconstructions of the Asian freshwater crab family Gecarcinucidae. Results: Although the Gecarcinucidae are not an element of an ancient Gondwana fauna, their subfamily Gecarcinucinae, and probably also the Liotelphusinae, evolved on the Indian Subcontinent and subsequently dispersed to Southeast Asia. Estimated by a model testing approach, this dispersal event took place during the Middle Eocene, and thus before the final collision of India and the Tibet-part of Eurasia. Conclusions: We postulate that the India and Southeast Asia were close enough for exchange of freshwater organisms during the Middle Eocene, before the final Indian--Eurasian collision. Our data support geological models that assume the Indian plate having tracked along Southeast Asia during its move northwards

Molecular phylogeny of the genera Palaemon and Palaemonetes (Decapoda, Caridea, Palaemonidae) from a European perspective

A molecular phylogenetic study by Murphy & Austin (2003) showed that Australian representatives of three shrimp genera of the family Palaemonidae (Palaemon, Palaemonetes, and Macrobrachium) do not cluster according to their generic classification. According to their results, the monophyly of these genera is questioned and the generic classification of the subfamily Palaemoninae is at stake. A large number of representatives of Palaemon and Palaemonetes inhabit European waters, including the type species of each genus. To clarify the phylogeny of these species, and thus the position of the generic names Palaemon and Palaemonetes on a phylogenetic tree, we obtained DNA sequences of the same genetic markers (16S mtDNA) as used by Murphy & Austin (2003) and re-addressed the question of taxonomy and phylogeny of these two genera within the subfamily Palaemoninae. Our results confirm the paraphyly of Palaemon and Palaemonetes. In contrast, the resulting monophyletic clades reflect the geographic distribution of the species according to their respective continents: Africa-Europe, Asia, Australia, and America. With the exception of Palaemon elegans the Afro-European species cluster in a way that would support monophyly of the two genera, if representatives from other continents are excluded. Possible taxonomic solutions are discussed.Research was partly funded by the postdoctoral grant from “Ministerio de Educación Cultura y Deporte” (Spain), and a Research contract “Ramón y Cajal” from “Ministerio de Ciencia y Tecnología” (Spain) to J.A.C.Peer Reviewe

A new species of Parastacus Huxley, 1879 (Crustacea, Decapoda, Parastacidae) from a swamp forest sothern Brazil

In this contribution we describe a new species of burrowing crayfi sh of the genus Parastacus Huxley, 1879 from a swamp forest in southern Brazil and determine its conservation status. Th e distinction of the new species is based on morphology and the mitochondrial DNA marker 16S rRNA. Th e extinction risk was assessed according to the sub-criterion B1 of IUCN that estimates the Extent of Occurrence (EOO). Parastacus tuerkayi sp. nov. is morphologically distinguishable from all species of Parastacus by having three lines of verrucous tubercles on the dorsomesial margin of the cheliped propodus and a suborbital angle exceeding 90°. Th e EOO comprises 647,674 km², and the species is classifi ed as “endangered”. Phylogenetic relationships indicate the distinct position of this new species in relation to the already described species

Phylogeography of the Atlantic Blue Crab Callinectes sapidus (Brachyura: Portunidae) in the Americas versus the Mediterranean Sea: Determining Origins and Genetic Connectivity of a Large-Scale Invasion

The American blue crab Callinectes sapidus is a particularly successful invader in estuarine ecosystems worldwide. Despite increasing awareness of its potential harm, the invasion history and underlying genetic diversity of this species within the Mediterranean Sea remain unknown. This study constitutes the first large-scale approach to study phylogeographic patterns of C. sapidus in Europe, facilitated by the first comparison of all currently available COI sequence data. For this investigation, 71 individuals of C. sapidus were newly analyzed and the entire COI gene was sequenced and used for a comparative phylogeographic analyses. For the first time, two separately used adjacent regions of this gene were combined in a single dataset. This allowed emphasizing the prevalence of three geographically defined lineages within the native range: (1) eastern North America, including the Gulf of Mexico, (2) the Caribbean, and (3) Brazil. New data from the Mediterranean reveal that non-native populations of C. sapidus are characterized by a conspicuously low genetic diversity (except for Turkey, where stocking took place), and that there is surprisingly low connectivity among established populations. The occurrence of strong genetic bottlenecks suggests few founder individuals. This confirms that, even under a scenario of restricted large-scale gene flow, a very limited number of invasive individuals is sufficient for a massive impact

Th2-dependent STAT6-regulated genes in intestinal epithelial cells mediate larval trapping during secondary Heligmosomoides polygyrus bakeri infection

Gastrointestinal helminths are a major health threat worldwide. Alternatively activated macrophages (AAMs) have been shown to contribute to host protection during secondary helminth infections. AAMs express effector molecules that depend on activation of the IL-4- or IL-13-induced transcription factor signal transducer and activator of transcription 6 (STAT6). However, the specific role of STAT6-regulated genes like Arginase-1 (Arg1) from AAMs or STAT6-regulated genes in other cell types for host protection remains unclear. To address this point, we generated mice expressing STAT6 only in macrophages (Mac-STAT6 mouse). In the model of Heligmosomoides polygyrus bakeri (Hpb) infection, Mac-STAT6 mice could not trap larvae in the submucosa of the small intestine after secondary infection. Further, mice lacking Arg1 in hematopoietic and endothelial cells were still protected from secondary Hpb infection. On the other hand, specific deletion of IL-4/IL-13 in T cells blunted AAM polarization, activation of intestinal epithelial cells (IECs) and protective immunity. Deletion of IL-4Rα on IEC also caused loss of larval trapping while AAM polarization remained intact. These results show that Th2-dependent and STAT6-regulated genes in IECs are required and AAMs are not sufficient for protection against secondary Hpb infection by mechanisms that remain to be investigated