Seascape genomics of the pink abalone (Haliotis corrugata): An insight into a cross-border species in the northeast Pacific coast.

Seascape genomics gives insight into the geographic and environmental factors shaping local adaptations. It improves the understanding of the potential effects of climate change, which is relevant to provide the basis for the international management of fishery resources. The pink abalone (Haliotis corrugata) is distributed from California, United States to Baja California Sur, Mexico, exposed to a latitudinal environmental gradient in the California Current System. Management of the pink abalone contrasts between Mexico and the United States; Mexico has an active fishery organized in four administrative areas, while the United States has kept the fishery in permanent closure since 1996. However, the impact of environmental factors on genetic variation along the species distribution remains unknown, and understanding this relationship is crucial for effective spatial management strategies. This study aims to investigate the neutral and adaptive genomic structure of H. corrugata. A total of 203 samples from 13 locations were processed using ddRADseq, and covering the species' distribution. Overall, 2,231 neutral, nine potentially adaptive and three genomic-environmental association loci were detected. The neutral structure identified two groups: 1) California, United States and 2) Baja California Peninsula, México. In addition, the adaptive structure analysis also detected two groups with genetic divergence observed at Punta Eugenia. Notably, the seawater temperature significantly correlated with the northern group (temperate) and the southern (warmer) group. This study is a valuable foundation for future research and conservation initiatives, emphasizing the importance of considering neutral and adaptive genetic factors when developing management strategies for marine species.

Mitochondrial phylogeography and molecular evolution of the rhodopsin visual pigment in troglobitic populations of Astyanax mexicanus (De Filippi, 1853).

Cave-adapted animals provide a unique opportunity to study the evolutionary mechanisms underlying phenotypic, metabolic, behavioral, and genetic evolution in response to cave environments. The Mexican tetra ( Astyanax mexicanus) is considered a unique model system as it shows both surface and cave-dwelling morphs. To date, at least 33 different cave populations have been identified, with phylogenetic studies suggesting an origin from at least two independent surface lineages, thereby providing a unique opportunity to study parallel evolution. In the present study, we carried out the most exhaustive phylogeographic study of A. mexicanus to date, including cave and surface localities, using two mitochondrial markers (cytochrome b (cyt b) and cytochrome c oxidase subunit I ( COI)) and nuclear rhodopsin visual pigment ( rho). Additionally, we inferred the molecular evolution of rho within the two contrasting environments (cave and surface) and across three geographic regions (Sierra de El Abra, Sierra de Guatemala, and Micos). In total, 267 individuals were sequenced for the two mitochondrial fragments and 268 individuals were sequenced for the rho visual pigment from 22 cave and 46 surface populations. Phylogeographic results based on the mitochondrial data supported the two-lineage hypothesis, except for the Pachón and Chica caves, whose introgression has been largely documented. The Sierra de El Abra region depicted the largest genetic diversity, followed by the Sierra de Guatemala region. Regarding the phylogeographic patterns of rho, we recovered exclusive haplogroups for the Sierra de El Abra (Haplogroup I) and Sierra de Guatemala regions (Haplogroup IV). Moreover, a 544 bp deletion in the rho gene was observed in the Escondido cave population from Sierra de Guatemala, reducing the protein from seven to three intramembrane domains. This change may produce a loss-of-function (LOF) but requires further investigation. Regarding nonsynonymous ( dN) and synonymous ( dS) substitution rates (omega values ω), our results revealed the prevailing influence of purifying selection upon the rho pigment for both cave and surface populations (ω<1), but relaxation at the El Abra region. Notably, in contrast to the other two regions, we observed an increase in the number of dN mutations for Sierra de El Abra. However, given that a LOF was exclusively identified in the Sierra de Guatemala region, we cannot dismiss the possibility of a pleiotropic effect on the Rho protein.

Molecular systematics of the Dichopetala genus group (Orthoptera: Phaneropteridae)

Introducción: El grupo de géneros Dichopetala se propuso recientemente después de una revisión del género Dichopetala Brunner von Wattenwyl, 1878. Actualmente, el grupo consta de ocho géneros y 44 especies distribuidas desde el sur de los Estados Unidos hasta el sur de México. Este acuerdo genérico, se basó únicamente en evidencia morfológica y se acompañó por discusiones sobre nuevos géneros erigidos, para los cuales no se probó su monofilia. Objetivo: Evaluar las relaciones filogenéticas entre especies representativas de los ocho géneros del grupo Dichopetala. Métodos: Generamos secuencias de ADN para un gen mitocondrial (Citocromo oxidasa I: COI) y dos marcadores de genes nucleares (28S, Histona III: H3), e incluimos especies de otros géneros de Phaneropterinae para probar la monofilia del grupo en estudio. Utilizamos modelos evolutivos bayesianos y de máxima verosimilitud. Resultados: Se respalda la monofilia del grupo Dichopetala y la monofilia de los géneros Dichopetala, Obolopteryx, Planipollex, Mactruchus y Rhabdocerca. Además, los géneros Acanthorintes y Pterodichopetala como parafiléticos. Los marcadores mitocondriales también sugieren que los géneros Rhabdocerca y Acanthorintes ampliamente distribuidos, pueden en realidad contener varias especies no vistas previamente. Conclusión: Se proporciona la primera contribución a la filogenia del grupo de Dichopetala y una definición filogenética y morfológica más robusta de algunos de los géneros involucrados.

Introduction: The Dichopetala genus group was proposed recently after revision of the genus Dichopetala Brunner von Wattenwyl, 1878. Currently, the group consists of eight genera and 44 species distributed from Southern United States to Southern Mexico. This generic arrangement was based solely on morphological evidence, and was accompanied by discussions on new erected genera, for which their monophyly was not tested. Objective: To assess the phylogenetic relationships among representative species of the eight genera of the Dichopetala group. Methods: We generated DNA sequences for one mitochondrial (Cytochrome oxidase I: COI) and two nuclear (28S, Histone III: H3) gene markers, and included species of other Phaneropterinae genera to test the monophyly of the ingroup; Bayesian and maximum likelihood evolutionary models were used. Results: The monophyly of the Dichopetala group and the monophyly of genera Dichopetala, Obolopteryx, Planipollex, Mactruchus and Rhabdocerca is supported. In addition, Acanthorintes and Pterodichopetala were recovered as paraphyletic. The mitochondrial markers also suggest that the widely distributed genera Rhabdocerca and Acanthorintes may actually contain various overlooked species. Conclusions: The first contribution on the Phylogeny of the Dichopetala group, and a more robust phylogenetic and morphological definition of some of the genera involved are provided.

3RAD-based systematics of the transitional Nearctic-Neotropical lubber grasshopper genus Taeniopoda (Orthoptera: Romaleidae).

The genus Taeniopoda Stål (Romaleidae) is a group of Nearctic-Neotropical grasshoppers whose systematics has been largely neglected. A recent phylogenetic study based on morphology and mitochondrial and nuclear markers failed to resolve the species boundaries in this genus and showed a lack of reciprocal exclusivity between T. eques (Burmeister) and T. tamaulipensis Rehn. Here we assessed the species limits and phylogenetic relationships in Taeniopoda based on 3RAD data, and evaluated the presence of gene flow and niche overlap between the above two species using clustering and ecological niche modelling (ENM) analyses to determine their taxonomic status. We performed de novo assembly of different 3RAD data sets with distinct parameters settings to explore whether they impact the recovered relationships. Ten species were consistently delimited, with T. picticornis and T. stali regarded as conspecific and the populations of T. auricornis from Guatemala representing a separate species. We maintained the specific status of T. eques and T. tamaulipensis, though our results suggest that they represent a ring species since their genetic composition appear to change gradually following a "loop form" along their geographical distribution. The phylogenomic analyses confirmed the paraphyly of Taeniopoda with respect to Romalea and recovered three major clades. Similar to previous studies, the relationships of our examined matrices were highly congruent despite their different levels of missing data. However, the similarity threshold and minimum number of samples that must share a locus for it to be retained impact the amount of loci and missing data of the matrices. This study demonstrates the utility of 3RAD to detect gene flow and to resolve species limits and phylogenetic relationships among closely related taxa.

A new synonym of the Neotropical parasitoid wasp genus Notiospathius (Braconidae, Doryctinae), with redescription of two species and description of five new species from Brazil.

A junior synonym of the parasitoid wasp genus Notiospathius Matthews and Marsh, Hansonorumsyn. n., with two new combinations, Notiospathius carolinae (Marsh) comb. n. and Notiospathius pauli (Marsh) comb. n., are proposed. Two species of Notiospathius from Brazil originally described in early twentieth century are redescribed, Notiospathius caudatus (Szépligeti) and Notiospathius diversus (Szépligeti). Five new species of Notiospathius from southern Brazil are also described: Notiospathius atrasp. n., Notiospathius johnlennonisp. n., Notiospathius novateutoniaesp. n., Notiospathius sulcatussp. n., and Notiospathius xanthofasciatussp. n. Most of the type specimens of the above new species were collected in the mid twentieth century in the Nova Teutonia region, which is now part of the municipality of Seara in the state of Santa Catarina.

DNA barcoding a highly diverse group of parasitoid wasps (Braconidae: Doryctinae) from a Mexican nature reserve.

BACKGROUND AND AIMS: The preliminary results of a DNA barcoding study of the doryctine fauna of parasitoid wasps from the Chamela-Cuixmala Biosphere Reserve in Mexico, a region dominated by tropical dry forest, are presented. So far, three field trips have been carried out to the reserve and 468 specimens have been collected, of which 407 cox1 sequences were obtained. MATERIALS AND METHODS: The general mixed Yule-coalescent model was applied to a phylogram to investigate the number of evolutionary units that can be detected from the DNA sequence data examined. RESULTS: A total of 185 barcoding species assigned to 20 identified doryctine genera were discriminated using the above model, 115 of which belong to the speciose genus Heterospilus, pointing out the extraordinary species richness of this subfamily of insects in a Mexican tropical dry forest. CONCLUSION: On the basis of the DNA barcodes generated, Ptesimogastroides Braet & van Achterberg is proposed to be a junior synonym of Ptesimogaster Marsh syn. nov. Neoheterospilus was also found deeply nested within a large Heterospilus clade, suggesting the paraphyly of the latter genus.