DNA barcoding and morphology revealed the existence of seven new species of squat lobsters in the family Munididae (Decapoda, Galatheoidea) in the southwestern Pacific.

Specimens of squat lobsters belonging to the family MunididaeAhyong et al., 2010, representing the genera Garymunida Macpherson & Baba, 2022, Trapezionida Macpherson & Baba, 2022 and Typhlonida Macpherson & Baba, 2022, were collected during several cruises around New Caledonia and Papua New Guinea, Southwest Pacific. The integrative study of these specimens revealed the presence of one new species in Garymunida, five in Trapezionida and one in Typhlonida. We describe and illustrate these new species, providing some new data on the taxonomy of several rare or scarcely studied species of Trapezionida. Molecular data from different markers (mitochondrial and nuclear) was also included, based on data availability, to support the taxonomic status of different species. Finally, a key to species for each genus is also provided.

Hidden species diversity and mito-nuclear discordance within the Mediterranean cone snail, Lautoconus ventricosus.

The Mediterranean cone snail, Lautoconus ventricosus, is currently considered a single species inhabiting the whole Mediterranean basin and the adjacent Atlantic coasts. Yet, no population genetic study has assessed its taxonomic status. Here, we collected 245 individuals from 75 localities throughout the Mediterranean Sea and used cox1 barcodes, complete mitochondrial genomes, and genome skims to test whether L. ventricosus represents a complex of cryptic species. The maximum likelihood phylogeny based on complete mitochondrial genomes recovered six main clades (hereby named blue, brown, green, orange, red, and violet) with sufficient sequence divergence to be considered putative species. On the other hand, phylogenomic analyses based on 437 nuclear genes only recovered four out of the six clades: blue and orange clades were thoroughly mixed and the brown one was not recovered. This mito-nuclear discordance revealed instances of incomplete lineage sorting and introgression, and may have caused important differences in the dating of main cladogenetic events. Species delimitation tests proposed the existence of at least three species: green, violet, and red + blue + orange (i.e., cyan). Green plus cyan (with sympatric distributions) and violet, had West and East Mediterranean distributions, respectively, mostly separated by the Siculo-Tunisian biogeographical barrier. Morphometric analyses of the shell using species hypotheses as factor and shell length as covariate showed that the discrimination power of the studied parameters was only 70.2%, reinforcing the cryptic nature of the uncovered species, and the importance of integrative taxonomic approaches considering morphology, ecology, biogeography, and mitochondrial and nuclear population genetic variation.

Nomenclatural changes in a taxonomically complex group (Amphipoda: Gammaridae).

The family Gammaridae is a large monophyletic group with a complicated taxonomy. A nomenclatural review of the taxonomic status of Pectenogammarus Reid, 1940 was conducted based on Hou & Sket (2016) and Sket & Hou (2018) phylogenetic proposals. These authors used the name Homoeogammarus Schellenberg, 1937 for a set of morphologically diverse taxa previously included mainly within Echinogammarus Stebbing, 1899. Unfortunately, the use of the name Homoeogammarus Schellenberg, 1937 is problematic. As a result of a detailed bibliographic review, we propose the name Pectenogammarus Reid, 1940 (stat. nov.) for the "Homoeogammarus" clade (Sket & Hou 2018), which results in 20 new combinations. In addition, two genera are here formally synonymised as follows: Pectenogammarus Reid, 1940 = Homoeogammarus Barnard et Barnard, 1983, syn. nov. = Laurogammarus G.S. Karaman, 1984, syn. nov. A synonymic catalogue is provided.

New records and species of deep-sea squat lobsters (Galatheoidea, Munidopsidae) from the Hawaiian Archipelago: an integrative approach using micro-CT and barcodes.

The Hawaiian Archipelago remains extensively under-sampled for many marine invertebrate taxa, including squat lobsters. During the last few years, several deep-sea expeditions carried out in the Pacific Ocean have conducted opportunistic collections of specimens and image data from the vicinity of Hawai'i. Here we describe a new species: Munidopsis hawaii sp. nov. and provide new records for Munidopsidae in the Archipelago and its associations. We illustrate and describe the new species using an integrative approach including micro-CT 3D imaging. Phylogenetic analyses of the species collected from seamounts from Hawai'i indicate that the new species represents a divergent lineage compared to morphologically similar species such as M. dispar and M. papanui. We also study the genetic distances for the species recorded in Hawai'i and other populations of the same species in the adjacent West Pacific. Three species are now known in the Hawaiian region. We also compiled identifications from images captured with ROVs in the area. These observations suggest that munidopsid species are common in the deep sea of Hawaiian waters below 1,000 m.

Proctodeal extrusion as a defensive behavioral response in blister beetles (Coleoptera: Meloidae).

Defensive mechanisms in blister beetles (Coleoptera: Meloidae) include a wide variety of behavioral responses, chemical defense, and conspicuous external colorations. Although some of these mechanisms have been previously described, proctodeal extrusion, a defensive behavior involving the extrusion of inner abdominal membranes from the proctodeal region which appear intensely red or orange colored when the hemolymph is seen through them, has not been reported to date. Here, we tested the ability to display proctodeal extrusion in response to threat stimuli in wild populations of three blister beetle species inhabiting Central Spain: Berberomeloe majalis (Linnaeus, 1758), Berberomeloe comunero Sánchez-Vialas, García-París, Ruiz & Recuero, 2020, and Physomeloe corallifer (Germar, 1818). In addition, we observed and recorded various other defensive behaviors such as immobility, antennal threat display, autohemorrhage (reflex bleeding), defecation, and thanatosis (death feigning). The frequency at which proctodeal extrusion was observed differed among species, as did the stress intensity needed for extrusion and the probability of proctodeal extrusion in response to a particular threatening stimulus. Our findings indicate that, although proctodeal extrusion might be a widespread potential defensive mechanism in Meloidae, the ability to elicit it is not generalized across lineages. Physomeloe and Berberomeloe are endemic to the semi-arid Mediterranean region, and species adapted to such a climate would have developed strategies that limit hydric stress such as proctodeal extrusion, which mirrors the effect of autohemorrhage but without the fluid loss.

New occurrences of squat lobsters of the genus Eumunida Smith, 1883 (Decapoda, Eumunididae) in New Caledonia, the Solomon Islands and Papua-New Guinea, with the description of a new species.

Examination of numerous specimens of squat lobsters of the genus Eumunida Smith, 1883 collected by French cruises along the coasts of New Caledonia, the Solomon Islands and Papua-New Guinea revealed the presence of six species, including a new species. The collection data of all of these species are recorded. The new species, E. turbulenta n. sp., is described and illustrated from New Caledonia and Chesterfield Islands.

On some squat lobsters from India (Decapoda, Anomura, Munididae), with description of a new species of Paramunida Baba, 1988.

Squat lobster specimens belonging to the family Munididae were recently collected along the southwestern coast of the mainland of India and in the Andaman Islands. The specimens belong to two known species, Agononida prolixa (Alcock, 1894) and Munida compacta Macpherson, 1997, and a new species, Paramunida bineeshi sp. nov. We here redescribe A. prolixa and describe and figure the new species. Munida compacta is newly recorded from India, and we figure the live coloration. In addition, molecular and phylogenetic analyses of two mitochondrial markers (16S rRNA and COI) revealed the phylogenetic relationships of M. compacta and P. bineeshi sp. nov. with their most closely related congeners. The genetic similarity among the individuals of M. compacta from different locations is also addressed.

A new species of squat lobster of the genus Hendersonida (Crustacea, Decapoda, Munididae) from Papua New Guinea.

Hendersonida parvirostris sp. nov. is described from Papua New Guinea. The new species can be distinguished from the only other species of the genus, H. granulata (Henderson, 1885), by the fewer spines on the dorsal carapace surface, the shape of the rostrum and supraocular spines, the antennal peduncles, and the length of the walking legs. Pairwise genetic distances estimated using the 16S rRNA and COI DNA gene fragments indicated high levels of sequence divergence between the new species and H. granulata. Phylogenetic analyses, however, recovered both species as sister species, supporting monophyly of the genus.

Limited long-distance dispersal success in a Western European fairy shrimp evidenced by nuclear and mitochondrial lineage structuring.

Anostraca are known by their ability for long-distance dispersal, but the existence in several species of deep, geographically structured mtDNA lineages suggests their populations are subjected to allopatric differentiation, isolation, and prevalence of local scale dispersion. Tanymastix stagnalis is one of the most widespread species of Anostraca and previous studies revealed an unclear geographical pattern of mtDNA genetic diversity. Here, we analyze populations from the Iberian and Italian Peninsulas, Central Europe, and Scandinavia, with the aim to characterize the patterns of genetic diversity in a spatio-temporal framework using mtDNA and nuclear markers to test gene flow among close populations. For these aims we built a time-calibrated phylogeny and carried out Bayesian phylogeographic analyses using a continuous diffusion model. Our results indicated that T. stagnalis presents a deeply structured genetic diversity, including 7 ancient lineages, some of them even predating the Pleistocene. The Iberian Peninsula harbors high diversity of lineages, with strong isolation and recent absence of gene flow between populations. Dispersal at local scale seems to be the prevailing dispersal mode of T. stagnalis, which exhibits a pattern of isolation-by-distance in the Iberian Peninsula. We remark the vulnerability of most of these lineages, given the limited known geographic distribution of some of them, and the high risk of losing important evolutionary potential for the species.

A new Mediterranean species of Dolistenus (Diplopoda, Platydesmida, Andrognathidae), with an updated key for the genus and the first contribution for a barcode database of European Platydesmida.

Dolistenus Fanzago, 1874 is a widespread Mediterranean millipede genus of the order Platydesmida, currently including three valid species, each with relict distributions. Here we describe a fourth species of Dolistenus, and characterize it using morphological and molecular (mitochondrial DNA) characters. We provide an updated key to the species of Dolistenus and the first COI barcode sequences for the new species and several other European representatives of the Andrognathidae (Platydesmida).

Revision of the squat lobsters of the genus Leiogalathea Baba, 1969 (Crustacea, Decapoda, Munidopsidae) with the description of 15 new species.

The genus Leiogalathea Baba, 1969 currently contains only two benthic species both occurring on the continental shelves and slope: L. laevirostris (Balss, 1913), widely reported in the Indo-Pacific region, and L. agassizii (A. Milne Edwards, 1880), from both sides of the Central Atlantic. A certain degree of morphological variability linked to their geographic distributions was previously noticed, mostly in L. laevirostris. In the present study, we revise numerous specimens collected from the Atlantic, Indian and Pacific Oceans, analysing morphological and molecular characters (COI and 16S rRNA). We found 15 new species; all of them are distinguished from L. laevirostris and L. agassizii by subtle but constant morphological differences and show clear genetic separation. Furthermore, L. imperialis (Miyake Baba, 1967), previously synonymized with L. laevirostris, was found to be a valid species. All species are described and illustrated. Species of the genus Leiogalathea are morphologically distinguishable on the basis of the spinulation of the carapace, the shape and the armature of the rostrum, the shape of the propodi of the walking legs, and the pattern of the setae covering on rostrum, carapace and chelae. Some species are barely discernible on the basis of these characters but are highly divergent genetically.

Three new species of squat lobsters of the genus Munidopsis Whiteaves, 1874, from Guadeloupe Island, Caribbean Sea (Crustacea, Decapoda, Munidopsidae).

The genus Munidopsis is one of the most diverse genera within squat lobsters. Here, three new species of Munidopsis, M. cornuata n. sp., M. senticosa n. sp., and M. turgida n. sp., from <500 m off Guadeloupe Island (Caribbean Sea), are fully described and illustrated. Among the Atlantic species of the genus, M. cornuata n. sp. belongs to the group of species having the dorsal surface of the carapace with spines and is most similar to M. robusta (A. Milne-Edwards, 1880), from the Gulf of Mexico and Caribbean Sea. Munidopsis senticosa n. sp. resembles M. barbarae (Boone, 1927) from the Bahamas and the Gulf of Mexico and M. penescabra Pequegnat Williams 1995, from off Georgia and Gulf of Mexico; the three species belong to the group having the carapace covered with sharp spines. Finally, M. turgida n. sp. is characterized by having the dorsal surface of the carapace, abdomen and pereiopods covered by granules; and resembles M. granulens Mayo, 1972, from NW Caribbean Sea. Apart from the morphological evidence, the analysis of mitochondrial genes (COI and 16S) supports establishing these new species, showing very high genetic divergences compared to their congeners (from 14.5 to 17% for COI, and 7.7 to 12.8% for 16S data).

Three new species of squat lobsters of the genus Fennerogalathea Baba, 1988 (Decapoda: Galatheidae) from the Pacific Ocean.

The genus Fennerogalathea Baba, 1988 was known to contain two species: F. chacei Baba, 1988, the type species, from the Philippines, Taiwan and Indonesia and F. chirostyloides Tirmizi & Javed, 1993 from the Bay of Bengal. In the present study, three new species of the genus are described and illustrated: F. chani n. sp. from Papua New Guinea, F. cultrata n. sp. from New Caledonia and Vanuatu and F. ensifera n. sp. from Fiji. The new species are morphologically distinguishable on the basis of the shape and spination of the rostrum and the presence/absence of a small spine on the frontal margin of the carapace. The species also show clear genetic differences (COI and 16S rDNA) among them.

Salt lakes of La Mancha (Central Spain): A hot spot for tiger beetle (Carabidae, Cicindelinae) species diversity.

The tiger beetle assemblage of the wetlands of La Mancha (central Spain) comprises nine species: Calomera littoralis littoralis, Cephalota maura maura, Cephalota circumdata imperialis, Cephalota dulcinea, Cicindela campestris campestris, Cicindela maroccana, Cylindera paludosa, Lophyra flexuosa flexuosa, and Myriochila melancholica melancholica. This assemblage represents the largest concentration of tiger beetles in a single 1º latitude / longitude square in Europe. General patterns of spatial and temporal segregation among species are discussed based on observations of 1462 specimens registered during an observation period of one year, from April to August. The different species of Cicindelini appear to be distributed over space and time, with little overlapping among them. Three sets of species replace each other phenologically as the season goes on. Most of the species occupy drying or dried salt lakes and salt marshes, with sparse vegetation cover. Spatial segregation is marked in terms of substrate and vegetation use. Calomera littoralis and Myriochila melancholica have been observed mainly on wet soils; Cephalota circumdata on dry open saline flats; Cephalota dulcinea and Cylindera paludosa in granulated substrates with typical halophytic vegetation; Cephalota maura is often present in man-modified areas. Cephalota circumdata and Cephalota dulcinea are included as species of special interest in the list of protected species in Castilla-La Mancha. Conservation problems for the Cicindelini assemblage arise from agricultural activities and inadequate use of sport vehicles. Attempts at restoring the original habitat, supressing old semi-industrial structures, may affect the spatial heterogeneity of the lakes, and have an effect on Cicindelinae diversity.