The α-carbonic anhydrases (α-CAs) are a large and ancient group of metazoan-specific enzymes. They generate bicarbonate from metabolic carbon dioxide and through calcium carbonate crystal formation play a key role in the regulation of mineralized structures. To better understand how α-CAs contribute to shell mineralization in the marine Mediterranean mussel ( Mytilus galloprovincialis ) we characterized them in the mantle. Phylogenetic analysis revealed that mollusc α-CA evolution was affected by lineage and species-specific events. Ten α-CAs were found in the Mediterranean mussel mantle and the most abundant form was named, MgNACR, as it grouped with oyster nacreins (NACR). Exposure of the Mediterranean mussel to reduced water salinity (18 vs 37 ppt), caused a significant reduction (p < 0.05) in mantle esterase activity and MgNACR transcript abundance (p < 0.05). Protonograms revealed multiple proteins in the mantle with α–CA hydratase activity and mapped to a protein with a similar size to that deduced for monomeric MgNACR. Our data indicate that MgNACR is a major α–CA enzyme in mantle and that by homology with oyster nacreins likely regulates mussel shell production. We propose that species-dependent α-CA evolution may contribute to explain the diversity of bivalve shell structures and their vulnerability to environmental changes.

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Biomineralization is the process by which living organisms acquired the capacity to accumulate minerals in tissues. Shells are the biomineralized exoskeleton of marine molluscs produced by the mantle but factors that regulate mantle shell building are still enigmatic. this study sought to identify candidate regulatory factors of molluscan shell mineralization and targeted family B G-protein coupled receptors (GpcRs) and ligands that include calcium regulatory factors in vertebrates, such as calcitonin (cALc). in molluscs, cALc receptor (cALcR) number was variable and arose through lineage and speciesspecific duplications. The Mediterranean mussel (Mytilus galloprovincialis) mantle transcriptome expresses six cALcR-like and two cALc-precursors encoding four putative mature peptides. Mussel cALcR-like are activated in vitro by vertebrate cALc but only receptor cALcRiic is activated by the mussel cALciia peptide (ec 50 = 2.6 ×10 −5 M). Ex-vivo incubations of mantle edge tissue and mantle cells with CALCIIa revealed they accumulated significantly more calcium than untreated tissue and cells. Mussel CALCIIa also significantly decreased mantle acid phosphatase activity, which is associated with shell remodelling. our data indicate the cALc-like system as candidate regulatory factors of shell mineralization. The identification of the CALC system from molluscs to vertebrates suggests it is an ancient and conserved calcium regulatory system of mineralization.

In this study, we describe a new Lampyridae subfamily, Chespiritoinae new subfamily, its sole genus Chespiritonew genus, and three new species: Chespirito zaragozainew species, Chespirito lloydinew species, and Chespirito ballantyneaenew species from the Neotropical portions of Mexico. Chespirito can be readily separated from all other known Lampyridae by the unique prosternum, characterized by being very wide, divided in the middle by a distinct suture forming two plates, with the anterior margin bearing a narrow inter-coxal process, the strongly setose filiform antennae, with antennomere III much smaller than all other antennomeres, the pronotum medially constricted (not in C. ballantyneae), with area adjacent to disc strongly punctate and with the presence of a strongly developed longitudinal carina. To test the placement of the genus within the Lampyridae, we obtained three genetic markers (18S rRNA, 28SrRNA, and cox1 mitochondrial DNA) from C. zaragozai and performed a maximum likelihood (ML) and Bayesian inference (BI) analysis. Our analyses rendered nearly identical tree topologies, with C. zaragozainew species recovered as an independent lineage as sister to Pollaclasis bifaria (Say) (Coleoptera, Lampyridae) + Cyphonocerus ruficollis Kiesenwetter (Coleoptera, Lampyridae)+Luciolinae, with a posterior probability of 96 for the BI analysis and UFBoot respectively of 91 for the ML analysis with the entire clade sister to Pterotus obscuripennis LeConte (Coleoptera, Lampyridae). A detailed examination of the morphology of Chespirito indicates that this lineage is divergent from all other known Lampyridae, which combined with the results of our analyses supports the erection of a new subfamily.

The Leptolycini are a group of Lycidae endemic to the West Indies. Leptolycini adult females have been hypothesized to be extreme paedomorphic (i.e., larviform), however, females and larvae of the group are currently unknown. Here we provide the first association of adult male and immature life stages from the Puerto Rico using DNA barcoding, also collections-based associations and descriptions of immature Leptolycini and the first description of a paedomorphic female from the Virgin Islands. To carry out these life-stage associations we prepared an in-depth review of the Leptolycini fauna of the Puerto Rican bank (Puerto Rico and Virgin Islands). Several new taxa and taxonomic arrangements are proposed: Cessator crypticusnew species, Cessator tortolensisnew species, Cessator obrienorumnew species; Dracolycus chupacabranew genus and species, Dracolycus marshallinew species; Leptolycus falsoheterocornisnew species, and Leptolycus viensisnew species. Nanolycus gnomus Kazantsev is moved to Cessator gnomus (Kazantsev) new combination, rendering Nanolycus Kazantsev a new junior synonym of Cessator Kazantsev. The subgenus Baholycus Bocak is a new junior synonym of Leptolycus Leng and Mutchler. Leptolycus heterocornis var. flavicollis Leng and Mutchler is elevated to Leptolycus flavicollis Leng and Mutchler new status; Leptolycus (Leptolycus) albicauda Kazantsev is a new junior synonym of Leptolycus flavicollis Leng and Mutchler. An updated key to the adults and immature forms of Leptolycini from the Puerto Rican bank and a discussion on the importance of scientific collections in biodiversity studies is also provided.

Since the description of the genus Cheguevaria as incertae sedis (Lampyridae), the placement of these beetles has been uncertain. This study is the first to address the placement of this genus based on a molecular phylogenetic analysis. We used three genes (18S rRNA, rrnl mitochondrial DNA and cox1 mitochondrial DNA) and a maximum likelihood approach with W-IQ-TREE to support Cheguevaria as a member of the Lampyridae and recognize it as the sole genus in the new subfamily Cheguevariinae stat. nov.

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Lycidae are among the better studied groups in the superfamily Elateroidea, however despite the progress in the taxonomic understanding of the Neotropical fauna, much still remains unknown and undescribed in the region. The description of the new genus Xenolycus gen. nov., from Serra dos Órgãos, a subrange of the Serra do Mar mountain range, in the Atlantic Rainforest in Rio de Janeiro State, Brazil, contributes to the knowledge of the Neotropical Lycidae fauna. The new genus can be distinguished from all other known Calopterini and Neotropical Lycidae by the combination of a pronotum with a wide, deep and strongly visible longitudinal cell in the disc area, the filiform antennae, the dehiscent elytra with reticulation strongly reduced and bearing only two weakly developed elytral costae and the mouthparts partially reduced, with rudimentary, barely visible mandibles. The type species, Xenolycus costae sp. nov., is illustrated and diagnostic characters and a discussion on the tribal placement of the new genus are provided.