The fairy shrimp genus Branchinella Sayce (Crustacea: Anostraca: Thamnocephalidae) in Western Australia,including a description of four new species

The genus Branchinella is diverse in Western Australia, with 18 species, including four new species described here. B. complexidigitata n. sp. is characterized by an intricate frontal appendage, unlike any within the genus. The other three are less remarkable; B. halsei n. sp. is like B. lyrifera, B. kadjikadji n. sp. belongs to the B. affinis group and B. nana n. sp. is similar to B. simplex; similarities are based on frontal appendage and to a lesser extent on the second antennae and penis. Only two species, B. affinis and B. longirostris, are common and widespread; many of the remainder being localized endemics. The high diversity in Western Australia is explained by broad latitudinal range, habitat diversity, and great age and isolation of the landscape.     

The evolving male: spinner dolphin (Stenella longirostris) ecotypes are divergent at Y chromosome but not mtDNA or autosomal markers

The susceptibility of the Y chromosome to sexual selection may make this chromosome an important player in the formation of reproductive isolating barriers, and ultimately speciation. Here, we investigate the role of the Y chromosome in phenotypic divergence and reproductive isolation of spinner dolphin (Stenella longirostris) ecotypes. This species contains six known ecotypes (grouped into four subspecies) that exhibit striking differences in morphology, habitat and mating system, despite having adjacent or overlapping ranges and little genetic divergence at previously studied mtDNA and autosomal markers. We examined the phylogeographic structure for all six ecotypes across the species range (n = 261, 17 geographic locations) using DNA sequences from three Y chromosome markers, two maternally inherited mitochondrial (mtDNA) markers, and a biparentally inherited autosomal intron. mtDNA and autosomal analyses revealed low divergence (most Φ_ST values <0.1) between ecotypes and geographic regions, concordant with previous studies. In contrast, Y intron analyses revealed fixed differences amongst the three most phenotypically divergent groups: S. l. longirostris vs. S. l. roseiventris vs. combined S. l. orientalis/S. l. centroamericana/Tres Marias ecotypes). Another ecotype (whitebelly), previously postulated to be a hybrid between the two phenotypically most divergent ecotypes, had Y haplotypes from both putative parent ecotypes, supporting a hybrid designation. Reduced introgression of the Y chromosome has previously been observed in other organisms ranging from insects to terrestrial mammals, and here we demonstrate this phenomenon in a marine mammal with high dispersal capabilities. These results indicate that reduced introgression of the Y chromosome occurs in a wide taxonomic range of organisms and support the growing body of evidence that rapid evolution of the Y chromosome is important in evolutionary diversification.     

Subspecies delineation amid phenotypic,geographic and genetic discordance in a songbird

Understanding the processes that drive divergence within and among species is a long‐standing goal in evolutionary biology. Traditional approaches to assessing differentiation rely on phenotypes to identify intra‐ and interspecific variation, but many species express subtle morphological gradients in which boundaries among forms are unclear. This intraspecific variation may be driven by differential adaptation to local conditions and may thereby reflect the evolutionary potential within a species. Here, we combine genetic and morphological data to evaluate intraspecific variation within the Nelson's (Ammodramus nelsoni) and salt marsh (Ammodramus caudacutus) sparrow complex, a group with populations that span considerable geographic distributions and a habitat gradient. We evaluated genetic structure among and within five putative subspecies of A. nelsoni and A. caudacutus using a reduced‐representation sequencing approach to generate a panel of 1929 SNPs among 69 individuals. Although we detected morphological differences among some groups, individuals sorted along a continuous phenotypic gradient. In contrast, the genetic data identified three distinct clusters corresponding to populations that inhabit coastal salt marsh, interior freshwater marsh and coastal brackish–water marsh habitats. These patterns support the current species‐level recognition but do not match the subspecies‐level taxonomy within each species—a finding which may have important conservation implications. We identified loci exhibiting patterns of elevated divergence among and within these species, indicating a role for local selective pressures in driving patterns of differentiation across the complex. We conclude that this evidence for adaptive variation among subspecies warrants the consideration of evolutionary potential and genetic novelty when identifying conservation units for this group.     

Phylogeographic patterns and conservation units of a vulnerable species,Cabot’s tragopan (<Emphasis Type="Italic">Tragopan caboti</Emphasis>), endemic to southeast China

Cabot’s tragopan (Tragopan caboti) is a pheasant endemic to southeast China and is protected under both national and global legislation due to ongoing decline in population size and increased habitat fragmentation. We investigated the phylogeographic patterns and examined the consistency between evolutionary units and assumed subspecies taxonomy in this species. Six populations across the whole species presenting a wide distribution range were sampled and two mitochondrial DNA segments (control region, CR and cytochrome b, cyt b) were used in this study. The results demonstrated a high level of genetic diversity (h = 0.97 in CR and 0.78 in cyt b) and significant differentiation among populations. Phylogenetic analyses strongly indicated two reciprocally monophyletic clades named the “West group” and “East group” that were not consistent with the present subspecies regional distribution. The divergence time between the two groups was estimated to be around 5.54 × 10⁵–8.7 × 10⁵ years ago, and the expansion times of the two groups were close (about 3 × 10⁵ years ago), indicating the effect of glaciation in intraspecific differentiation. Based on the results of genetic analyses combined with geographic isolation and distinct population history, our findings suggest that two management units (MUs) should be defined in T. caboti for conservation.     

Evolution along the Great Rift Valley: phenotypic and genetic differentiation of East African white‐eyes (Aves,Zosteropidae)

The moist and cool cloud forests of East Africa represent a network of isolated habitats that are separated by dry and warm lowland savannah, offering an opportunity to investigate how strikingly different selective regimes affect species diversification. Here, we used the passerine genus Zosterops (white‐eyes) from this region as our model system. Species of the genus occur in contrasting distribution settings, with geographical mountain isolation driving diversification, and savannah interconnectivity preventing differentiation. We analyze (1) patterns of phenotypic and genetic differentiation in high‐ and lowland species (different distribution settings), (2) investigate the potential effects of natural selection and temporal and spatial isolation (evolutionary drivers), and (3) critically review the taxonomy of this species complex. We found strong phenotypic and genetic differentiation among and within the three focal species, both in the highland species complex and in the lowland taxa. Altitude was a stronger predictor of phenotypic patterns than the current taxonomic classification. We found longitudinal and latitudinal phenotypic gradients for all three species. Furthermore, wing length and body weight were significantly correlated with altitude and habitat type in the highland species Z. poliogaster. Genetic and phenotypic divergence showed contrasting inter‐ and intraspecific structures. We suggest that the evolution of phenotypic characters is mainly driven by natural selection due to differences in the two macro‐habitats, cloud forest and savannah. In contrast, patterns of neutral genetic variation appear to be rather driven by geographical isolation of the respective mountain massifs. Populations of the Z. poliogaster complex, as well as Z. senegalensis and Z. abyssinicus, are not monophyletic based on microsatellite data and have higher levels of intraspecific differentiation compared to the currently accepted species.     

Phylogenetic and diversity patterns of Blanus worm lizards (Squamata: Amphisbaenia): insights from mitochondrial and nuclear gene genealogies and species tree

Phylogenetic and phylogeographic patterns of amphisbaenians are poorly known. Molecular data from mitochondrial and nuclear loci are particularly needed for amphisbaenian phylogeny and taxonomy because their specializations to subterranean habits make morphology poorly informative and the occurrence of cryptic species probable. The Mediterranean genus Blanus includes five species – three of them have been recently studied mainly at the mitochondrial level. In this study, we collected mitochondrial (16S and nd4) and nuclear (mc1r and pomc) sequences from 49 specimens, including multiple individuals for each of the five species. We used multilocus coalescent‐based species‐tree inference and single‐gene analyses to estimate phylogenetic relationships among Blanus and to assess patterns of intraspecific differentiation within all the five species. Species‐tree and single‐gene phylogenies provided strong support for the Anatolian worm lizard B. strauchi lying outside a clade comprising all other congeners, with a sister relationship between the Iberian clade (B. cinereus and B. mariae) and the North African clade (B. tingitanus and B. mettetali). Mitochondrial and nuclear data supported the genetic distinctiveness of the recently described B. mariae and also indicated that the distribution of this species is wider than previously known and overlaps with B. cinereus in central Portugal. Blanus tingitanus showed two phylogeographic groups, from the northern and the southern portion of the range, respectively, having high mitochondrial and nuclear divergence and a possible contact zone in northwestern Morrocco. Finally, high genetic variation was found within B. mettetali and B. strauchi, suggesting in the latter case, the occurrence of cryptic taxa to be tested by further research.     

High chloroplast haplotype diversity in the endemic legume <Emphasis Type="Italic">Oxytropis chankaensis</Emphasis> may result from independent polyploidization events

Oxytropis chankaensis Jurtz. (Fabaceae) is an endangered perennial tetraploid species endemic to the Khanka Lake coast. In Russia, O. chankaensis is distributed across a very restricted zone along the western shore of this lake. To characterise all known populations of this species, we assessed the genetic diversity of four noncoding regions of chloroplast DNA (cpDNA). Variable sites detected within the trnL–trnF, the petG–trnP, and the trnS–trnG regions allowed the identification of seven haplotypes. On the other hand, no variation was found in the trnH–psbA region. O. chankaensis exhibited an overall low level of nucleotide diversity (π = 0.00052) but a marked haplotype diversity (h = 0.718). A combination of three or four haplotypes was found in each population, and most of the cpDNA variation (above 90%) was distributed within populations. The level of genetic structure that we detected in O. chankaensis using maternal plastid DNA markers was much lower (G _ST = 0.037) than the average that is estimated for angiosperms. We found no evidence for isolation by distance or for phylogeographic structuring in O. chankaensis. Our data suggest that autopolyploidy has arisen more than once in the evolutionary history of this species. Repetitive expansion and contraction during past and ongoing demographic events both seem to be involved in shaping the current genetic structure of O. chankaensis. This study provides valuable information for developing the most appropriate strategy for conserving this endemic species with a narrow habitat range.     

Mitochondrial DNA diversity of the vulnerable Chinese Egret (Egretta eulophotes) from China

The genetic diversity and population structure of the vulnerable Chinese Egret (Egretta eulophotes) were surveyed in the present study from three archipelagoes that cover the most southerly to the very northerly parts of the Chinese distribution range of this species, using a 433-bp fragment of the mitochondrial control region (CR). Among 90 individual samples, 31 different haplotypes were defined by 30 polymorphic sites. Overall haplotype diversity, nucleotide diversity and mean sequence divergence (p-distance) of this egret were 0.920, 0.0088 and 1.11%, respectively. NJ tree and parsimony network for the CR haplotypes of the Chinese Egret showed little genetic structure, and analysis of molecular variance indicated low but significant genetic differentiation (haplotype-based Φ_ST = 0.03267, P < 0.05 and distance-based Φ_ST = 0.04194, P < 0.05) among populations. The significant Fu’s F _S tests (Fu’s F _S  = −16.946, P < 0.01) and mismatch distribution analysis (τ = 4.463, SSD = 0.0081, P = 0.12) suggested that the low genetic differentiation and little geographical structure of the genetic differentiation might be explained by the population expansion. The Mantel test (haplotype-based F _ST, r = 0.639, P = 0.34 and distance-based F _ST, r = 0.947, P = 0.15) suggest that the significant genetic differentiation among populations was likely due to isolation by distance.     

Deep sympatric mtDNA divergence in the autumnal moth (Epirrita autumnata)

Deep sympatric intraspecific divergence in mtDNA may reflect cryptic species or formerly distinct lineages in the process of remerging. Preliminary results from DNA barcoding of Scandinavian butterflies and moths showed high intraspecific sequence variation in the autumnal moth, Epirrita autumnata. In this study, specimens from different localities in Norway and some samples from Finland and Scotland, with two congeneric species as outgroups, were sequenced with mitochondrial and nuclear markers to resolve the discrepancy found between mtDNA divergence and present species‐level taxonomy. We found five COI sub‐clades within the E. autumnata complex, most of which were sympatric and with little geographic structure. Nuclear markers (ITS2 and Wingless) showed little variation and gave no indications that E. autumnata comprises more than one species. The samples were screened with primers for Wolbachia outer surface gene (wsp) and 12% of the samples tested positive. Two Wolbachia strains were associated with different mtDNA sub‐clades within E. autumnata, which may indicate indirect selection/selective sweeps on haplotypes. Our results demonstrate that deep mtDNA divergences are not synonymous with cryptic speciation and this has important implications for the use of mtDNA in species delimitation, like in DNA barcoding.     

Prominent intraspecific genetic divergence within Anopheles gambiae sibling species triggered by habitat discontinuities across a riverine landscape

The Anopheles gambiae complex of mosquitoes includes malaria vectors at different stages of speciation, whose study enables a better understanding of how adaptation to divergent environmental conditions leads to evolution of reproductive isolation. We investigated the population genetic structure of closely related sympatric taxa that have recently been proposed as separate species (An. coluzzii and An. gambiae), sampled from diverse habitats along the Gambia river in West Africa. We characterized putatively neutral microsatellite loci as well as chromosomal inversion polymorphisms known to be associated with ecological adaptation. The results revealed strong ecologically associated population subdivisions within both species. Microsatellite loci on chromosome‐3L revealed clear differentiation between coastal and inland populations, which in An. coluzzii is reinforced by a unusual inversion polymorphism pattern, supporting the hypothesis of genetic divergence driven by adaptation to the coastal habitat. A strong reduction of gene flow was observed between An. gambiae populations west and east of an extensively rice‐cultivated region apparently colonized exclusively by An. coluzzii. Notably, this ‘intraspecific’ differentiation is higher than that observed between the two species and involves also the centromeric region of chromosome‐X which has previously been considered a marker of speciation within this complex, possibly suggesting that the two populations may be at an advanced stage of differentiation triggered by human‐made habitat fragmentation. These results confirm ongoing ecological speciation within these most important Afro‐tropical malaria vectors and raise new questions on the possible effect of this process in malaria transmission.     

Phylogenetic relationships among North Atlantic redfish (genus Sebastes) as revealed by mitochondrial DNA sequence analyses

Species structure and phylogenetic relationships among the four currently recognised North Atlantic redfish species, Sebastes mentella (‘deep‐sea’ and ‘oceanic’ phenotype), S. marinus (including ‘giant’ phenotype), S. fasciatus and S. viviparus, were investigated by sequencing the complete mitochondrial NADH dehydrogenase subunit 3 (ND3) gene for 313 individuals (333 including outliers). Low levels of sequence divergence of 0.3–2.3% between the North Atlantic Sebastes haplotypes, low resolution in phylogenetic trees and a star‐like statistical parsimony network indicate a population bottleneck and/or founder event with a subsequent population expansion and a rapid speciation in North Atlantic Sebastes. Diagnostic mutations within the ND3 gene were recognised for some of the species. The results lead to the hypothesis that the ancestral haplotype lineage is now very rare or has suffered extinction and that the most basal lineage is found in S. viviparus. The results further indicate direct descendants in the S. fasciatus and S. marinus lineages from the S. mentella lineage, whereas the S. viviparus lineage originates from an earlier division. The observation of two haplotype lineages in S. marinus with a relatively high level of intraspecific genetic divergence, points towards a possible cryptic speciation.     

Evidence of complex phylogeographic structure for the threatened rodent <Emphasis Type="Italic">Leopoldamys neilli</Emphasis>, in Southeast Asia

Leopoldamys neilli is a threatened murine rodent species endemic to limestone karsts of Thailand. We have studied the phylogeography of L. neilli using two mitochondrial markers (cytb, COI) and one nuclear fragment (bfibr), in order to assess the influence of its endemicity to karst habitat. One hundred fifteen individuals of L. neilli were collected in 20 localities throughout the geographic range of this species in Thailand. Our study revealed strong geographic structure of the mtDNA genetic diversity: six highly differentiated, allopatric genetic lineages were observed in our dataset. They exhibit a very high degree of genetic divergence, low gene flow among lineages and low levels of haplotype and nucleotide diversities within lineages. Our results suggest that L. neilli’s populations are highly fragmented due to the scattered distribution of its karst habitat. The most divergent lineage includes the populations from western Thailand, which have been separated from the other genetic lineages since at least the Early Pleistocene. The other lineages are more closely related and have diverged since the Middle Pleistocene. This study revealed an unexpected high level of genetic differentiation within L. neilli and highlighted the high endemicity of this species to limestone karsts. Our results enhance the importance of protecting limestone habitats to preserve not only the species but also intraspecific diversity.     

Are habitat fragmentation,local adaptation and isolation‐by‐distance driving population divergence in wild rice Oryza rufipogon?

Habitat fragmentation weakens the connection between populations and is accompanied with isolation by distance (IBD) and local adaptation (isolation by adaptation, IBA), both leading to genetic divergence between populations. To understand the evolutionary potential of a population and to formulate proper conservation strategies, information on the roles of IBD and IBA in driving population divergence is critical. The putative ancestor of Asian cultivated rice (Oryza sativa) is endangered in China due to habitat loss and fragmentation. We investigated the genetic variation in 11 Chinese Oryza rufipogon populations using 79 microsatellite loci to infer the effects of habitat fragmentation, IBD and IBA on genetic structure. Historical and current gene flows were found to be rare (m_h = 0.0002–0.0013, m_c = 0.007–0.029), indicating IBD and resulting in a high level of population divergence (F_ST = 0.343). High within‐population genetic variation (H_E = 0.377–0.515), relatively large effective population sizes (N_e = 96–158), absence of bottlenecks and limited gene flow were found, demonstrating little impact of recent habitat fragmentation on these populations. Eleven gene‐linked microsatellite loci were identified as outliers, indicating local adaptation. Hierarchical AMOVA and partial Mantel tests indicated that population divergence of Chinese O. rufipogon was significantly correlated with environmental factors, especially habitat temperature. Common garden trials detected a significant adaptive population divergence associated with latitude. Collectively, these findings imply that IBD due to historical rather than recent fragmentation, followed by local adaptation, has driven population divergence in O. rufipogon.     

Conflicting patterns of DNA barcoding and taxonomy in the cicada genus Tettigettalna from southern Europe (Hemiptera: Cicadidae)

DNA barcodes have great potential to assist in species identification, especially when high taxonomical expertise is required. We investigated the utility of the 5′ mitochondrial cytochrome c oxidase I (COI) region to discriminate between 13 European cicada species. These included all nine species currently recognized under the genus Tettigettalna, from which seven are endemic to the southern Iberian Peninsula. These cicadas have species‐specific male calling songs but are morphologically very similar. Mean COI divergence between congeners ranged from 0.4% to 10.6%, but this gene was proven insufficient to determine species limits within genus Tettigettalna because a barcoding gap was absent for several of its species, that is, the highest intraspecific distance exceeded the lowest interspecific distance. The genetic data conflicted with current taxonomic classification for T. argentata and T. mariae. Neighbour‐joining and Bayesian analyses revealed that T. argentata is geographically structured (clades North and South) and might constitute a species complex together with T. aneabi and T. mariae. The latter diverges very little from the southern clade of T. argentata and shares with it its most common haplotype. T. mariae is often in sympatry with T. argentata but it remains unclear whether introgression or incomplete lineage sorting may be responsible for the sharing of haplotypes. T. helianthemi and T. defauti also show high intraspecific variation that might signal hidden cryptic diversity. These taxonomic conflicts must be re‐evaluated with further studies using additional genes and extensive morphological and acoustic analyses.     

Comparative phylogeography of two seastars and their ectosymbionts within the Coral Triangle

Repeated exposure and flooding of the Sunda and Sahul shelves during Pleistocene sea‐level fluctuations is thought to have contributed to the isolation and diversification of sea‐basin populations within the Coral Triangle. This hypothesis has been tested in numerous phylogeographical studies, recovering an assortment of genetic patterns that the authors have generally attributed to differences in larval dispersal capability or adult habitat specificity. This study compares phylogeographical patterns from mitochondrial COI sequences among two co‐distributed seastars that differ in their adult habitat and dispersal ability, and two seastar ectosymbionts that differ in their degree of host specificity. Of these, only the seastar Linckia laevigata displayed a classical pattern of Indian‐Pacific divergence, but with only moderate genetic structure (Φ_CT = 0.067). In contrast, the seastar Protoreaster nodosus exhibited strong structure (Φ_CT = 0.23) between Teluk Cenderawasih and the remainder of Indonesia, a pattern of regional structure that was echoed in L. laevigata (Φ_CT = 0.03) as well as its obligate gastropod parasite Thyca crystallina (Φ_CT = 0.04). The generalist commensal shrimp, Periclimenes soror showed little genetic structuring across the Coral Triangle. Despite species‐specific phylogeographical patterns, all four species showed departures from neutrality that are consistent with massive range expansions onto the continental shelves as the sea levels rose, and that date within the Pleistocene epoch. Our results suggest that habitat differences may affect the manner in which species responded to Pleistocene sea‐level fluctuations, shaping contemporary patterns of genetic structure and diversity.     

Substantial differences in genetic diversity and spatial structuring among (cryptic) amphipod species in a mountainous river basin

1. Recent advances in molecular methods foster the documentation of small spatial scale biological diversity over large geographical areas. These advances allow to correctly record α-diversity, but also enable biomonitoring that describes intraspecific molecular diversity, providing valuable insights into the contemporary history of species. Such information is essential for the accurate monitoring of freshwater communities and provides a promising tool to identify conservation priorities at various spatial scales.
2. Here, we combined morphological species determinations with genetic characterisation via DNA barcoding and species distribution modelling. We aimed to investigate whether closely related amphipod species occupying overlapping ecological niches and occurring in partial sympatry, demonstrate similar spatial patterns of intraspecific genetic diversity and share comparable population histories. Therefore, we characterised the amphipod fauna within the Kinzig catchment (1,058 km², Hesse, Central Germany) that is a tributary of the Main River and part of the long-term ecological research network using genetics.
3. Our genetic analysis revealed two more taxonomic entities than previously known. The most common species was Gammarus fossarum clade 11 (or type B), followed by Gammarus roeselii clade C, Gammarus pulex clade D, G. pulex clade B and a very rare previously unknown lineage within the G. fossarum-species complex, which we refer to as G. fossarum clade RMO. These five taxa differed in their intraspecific genetic diversity, with G. fossarum clade 11 demonstrating the highest diversity and having a prominent small-scale pattern with endemic haplotypes in headwater regions. Distributions were predicted for the three most abundant molecularly identified species.
4. The upstream reaches maintained high intraspecific α- and β-diversity, pointing towards a more complex population structure of G. fossarum clade 11. This highlights the importance of considering intraspecific diversity for the conservation of individual species. DNA-based species distribution models shed light on species-specific habitat preferences, and showed spatial distribution patterns that supported ecological inference and conservation management. Barcoding specimens prior to modelling can increase robustness and performance of distribution models as juveniles can be incorporated, and cryptic species complexes disentangled.
5. Our integrative study contributes to the further development of science-informed and holistically considered effective conservation measures. Some poorly dispersing hololimnic species may serve as representatives for our understanding of the natural history of the local communities in headwater regions—and their protection. Intraspecific genetic diversity should be considered in conservation management decisions as it can provide valuable information on past and present population demography, connectivity, and recovery processes of species—information that rarely can be achieved by traditional monitoring approaches.

     

Genetic structure of the Caribbean giant barrel sponge Xestospongia muta using the I3-M11 partition of COI

In recent years, reports of sponge bleaching, disease, and subsequent mortality have increased alarmingly. Population recovery may depend strongly on colonization capabilities of the affected species. The giant barrel sponge Xestospongia muta is a dominant reef constituent in the Caribbean. However, little is known about its population structure and gene flow. The 5′-end fragment of the mitochondrial gene cytochrome oxidase subunit I is often used to address these kinds of questions, but it presents very low intraspecific nucleotide variability in sponges. In this study, the usefulness of the I3-M11 partition of COI to determine the genetic structure of X. muta was tested for seven populations from Florida, the Bahamas and Belize. A total of 116 sequences of 544 bp were obtained for the I3-M11 partition corresponding to four haplotypes. In order to make a comparison with the 5′-end partition, 10 sequences per haplotype were analyzed for this fragment. The 40 resulting sequences were of 569 bp and corresponded to two haplotypes. The nucleotide diversity of the I3-M11 partition (π = 0.00386) was higher than that of the 5′-end partition (π = 0.00058), indicating better resolution at the intraspecific level. Sponges with the most divergent external morphologies (smooth vs. digitate surface) had different haplotypes, while those with the most common external morphology (rough surface) presented a mixture of haplotypes. Pairwise tests for genetic differentiation among geographic locations based on F _ST values showed significant genetic divergence between most populations, but this genetic differentiation was not due to isolation by distance. While limited larval dispersal may have led to differentiation among some of the populations, the patterns of genetic structure appear to be most strongly related to patterns of ocean currents. Therefore, hydrological features may play a major role in sponge colonization and need to be considered in future plans for management and conservation of these important components of coral reef ecosystems. Communicated by Biology Editor Dr Ruth Gates     

New insights into the systematics of Malagasy mongoose‐like carnivorans (Carnivora,Eupleridae, Galidiinae) based on mitochondrial and nuclear DNA sequences

The Malagasy carnivorans (Eupleridae) comprise seven genera and up to ten species, depending on the authority, and, within the past decades, two new taxa have been described. The family is divided into two subfamilies, the Galidiinae, mongoose‐like animals, and the Euplerinae, with diverse body forms. To verify the taxonomic status of Galidiinae species, including recently described taxa, as well as some recognized subspecies, we studied intrageneric genetic variation and structure, using both mitochondrial and nuclear markers. Our results suggest the recognition of four species in the Galidiinae, rendering each genus monospecific. We propose to recognize three subspecies in Galidia elegans (G. e. dambrensis, G. e. elegans, and G. e. occidentalis), two subspecies in Mungotictis decemlineata (M. d. decemlineata and M. d. lineata), and two subspecies in Galidictis fasciata (G. f. fasciata and G. f. grandidieri, the latter was recently described as a distinct species). Our results indicate also that Salanoia durrelli should be treated as a junior synonym of Salanoia concolor. Low levels of intraspecific divergence revealed some geographical structure for the Galidiinae taxa, suggesting that environmental barriers have isolated certain populations in recent geological time. All taxa, whether at the species or subspecies level, need urgent conservation attention, particularly those with limited geographical distributions, as all are threatened by forest habitat degradation.     

Species designation of the Bruneau Dune tiger beetle (Cicindela waynei) is supported by phylogenetic analysis of mitochondrial DNA sequence data

Beetles comprise nearly one quarter of described species and show high levels of morphological and ecological diversification. Because of their wide distribution, ease of detection, and correlation of species richness patterns with other taxa, tiger beetles have been recommended for use as a global indicator of regional biodiversity, requiring accurate taxonomic designations. The Bruneau Dune tiger beetle (Cicindela waynei), whose habitat consists of an isolated dune field in southern Idaho, was recently described as a distinct species from the St. Anthony Dunes tiger beetle (C. arenicola) based on morphological characteristics. While these characteristics include distinct differences in genital morphology that could indicate intrinsic reproductive isolation, morphological characteristics have sometimes been misleading in tiger beetle taxonomy. To evaluate genetic support for this species designation, we analyzed 1,751 base pairs of mitochondrial DNA sequence from 147 tiger beetles collected throughout the range of both C. arenicola and C. waynei. Maximum-likelihood and Bayesian phylogenetic analyses indicated monophyly for C. waynei on a well-supported, short branch nested within C. arenicola. Bayesian species delimitation analyses strongly supported C. waynei as a distinct species (speciation probability = 1.0) with the estimated time of divergence ca. 14,500–67,000 years ago. This lack of reciprocal monophyly and recency of speciation is consistent with C. waynei as a member of an evolutionary front where speciation has occurred at a rapid rate. Mitochondrial sequence data supports the species designation of C. waynei, emphasizing the need to determine appropriate management for this species and its restricted habitat.