Single Widespread Species Research Articles

A new species in the Cyrtodactylus intermedius (Squamata: Gekkonidae) group from an isolated limestone karst formation in southwestern Cambodia

The gekkonid lizard Cyrtodactylus intermedius was formerly considered to be a single widespread species in hilly areas across eastern Thailand through southern Vietnam but has recently been partitioned into a complex of 12 nominal species across its range. A population belonging to the C. intermedius group was recently found in an isolated limestone karst block in Kampot Province in southwestern Cambodia, part of which lies within the recently designated Phnom Preah Kuhear Loung Natural Heritage Site. Comparisons of morphometric, meristic, qualitative morphological and color pattern data, as well as a molecular analysis using the mitochondrial ND2 gene, revealed that this population differs from all other named members of the C. intermedius group, and so is described here as a new species. The karst-dwelling C. regicavernicolus sp. nov. was recovered as the sister species to C. laangensis, the most geographically proximate member of the complex and one that is also restricted to a small limestone karst habitat.

What’s in a name? Using species delimitation to inform conservation practice for Chinese giant salamanders (Andrias spp.)

Abstract Genetically-defined biodiversity units must align with practical conservation frameworks, and most conservation is conducted at the species level. Chinese giant salamanders have traditionally been interpreted as the single widespread species Andrias davidianus, but molecular studies have reinterpreted this taxon as representing multiple allopatric clades, and competing taxonomic hypotheses support different numbers of candidate species. We conducted species delimitation analyses using tree-based models (General Mixed Yule Coalescent, Poisson Tree Processes) and alignment-based models (Bayesian Phylogenetics and Phylogeography) to interpret diversification across Andrias within a comparative systematic framework, using 30 mitogenomes representing all recognised Chinese clades. Nearly all tested models provide support for at least seven statistically-resolved Chinese species-level lineages, and most provide support for nine species. Only four species have available names. Chinese Andrias populations are Critically Endangered, but unnamed species cannot be incorporated into national or international conservation frameworks and risk being excluded from recovery efforts. We urge taxonomists and conservation practitioners to focus more attention on the world’s largest amphibians, and non-standard taxonomic approaches may be required to name these species before they disappear.

Chromatic polymorphism in Trichomycterus jacupiranga from eastern Brazilian Coastal basins (Siluriformes: Trichomycteridae).

Trichomycterinae catfishes often have high intraspecific variability in colour patterns that may be associated with ontogenetic changes or habitat preferences. In species of the eastern South American genus Trichomycterus s.s., some cases of chromatic polymorphism have been reported but colour pattern is still considered an important tool for species identification. Herein, we first describe chromatic polymorphism in the geographically widespread T. jacupiranga, comparing populations from Tijuca National Park and Ribeira do Iguape basin, identifying four syntopic colour morphs. In addition, we performed a phylogenetic analysis using partial sequences of the mitochondrial gene 12Ss gene for 16 individuals of T. jacupiranga, with a maximum of 0.2% of genetic distance, corroborating T. jacupiranga as a single widespread species. Finally, based on our results and field observations, we concluded that it is not possible at the present to associate chromatic polymorphism in T. jacupiranga with habitat preferences, since specimens with different colouration in variable ontogenetic stages were found at the same microhabitats.

Sphagnum diabolicum sp. nov. and S. magniae sp. nov.; morphological variation and taxonomy of the “S. magellanicum complex”

Until a few years ago, Sphagnum magellanicum was understood to be a single widespread species with an intercontinental range. Recent work by Norwegian sphagnologists showed that S. magellanicum s.str. is restricted to southern South America and plants known as S. magellanicum in Europe should be referred to S. divinum and S. medium. In a separate publication, we showed that there are two additional major clades in eastern North America, and we describe them herein as S. diabolicum and S. magniae. These species are very hard to distinguish morphologically (and also from S. divinum and S. medium) but are distinct phylogenetically, ecologically and geographically, and are important units of biodiversity. Morphological variation within and between species is photographically documented.

A review of bats of the genus Pseudoromicia (Chiroptera: Vespertilionidae) with the description of a new species

The Cameroon Volcanic Line, which divides the Congo Basin fauna from the West African fauna, is a known area of high endemism for various taxa, but the region’s bat fauna has received little attention. We review variation in morphological and molecular (mitochondrial Cytochrome b) characters in the Tropical African vespertilionid bat genus Pseudoromicia. Assessment of this variation indicates the existence of a new species of Pseudoromicia, from the Mbam Minkom Massif in the Centre Region of Cameroon. The new species is diagnosable by sequence data and is morphologically similar to its putative sister taxon, P. kityoi, from Uganda. Although we suggest that it be assigned to the IUCN category of Data Deficient, there should be some concern as to the conservation status of this species: the Mbam Minkom Massif ecosystem is threatened due to lack of legal conservation frameworks and exposure to increasing human pressure. The new species is in a clade with P. roseveari and P. kityoi. These three species may be relicts of a single widespread species originating in the West African “white-winged” group of Pseudoromicia that then spread east across the tropical moist broadleaf forest into East Africa, and are now restricted to a few upland rainforest patches in West Africa (P. roseveari), in outliers of the Cameroon Volcanic Line region (Pseudoromicia sp.), and the Lake Victoria area (P. kityoi). The smaller, white-winged species are hypothesized to be ancestral, with one extant putative species (P. rendalli) also extending into East and southern Africa (Van Cakenberghe & Happold, 2013). The larger, dark-winged taxa likely dispersed to East Africa and subsequently back to West Africa (e.g., Pseudoromicia sp., P. roseveari). Our data illustrate the potential importance of the Dahomey Gap and climatic changes in the evolution of this group of species. http://zoobank.org/urn:lsid:zoobank.org:pub:30929BAA-4043-422D-B209-16CAB826043E

Bumblebees of the hypnorum-complex world-wide including two new near-cryptic species (Hymenoptera: Apidae)

The hypnorum-complex of bumblebees (in the genus Bombus Latreille, 1802) has been interpreted as consisting of a single widespread Old-World species, Bombus hypnorum (Linnaeus, 1758) s. lat., and its closely similar sister species in the New World, B. perplexus Cresson, 1863. We examined barcodes for evidence of species’ gene coalescents within this species complex, using the closely related vagans-group to help calibrate Poisson-tree-process models to a level of branching appropriate for discovering species. The results support seven candidate species within the hypnorum-complex (Bombus taiwanensis Williams, Sung, Lin & Lu, 2022, B. wolongensis Williams, Ren & Xie sp. nov., B. bryorum Richards, 1930, B. hypnorum, B. koropokkrus Sakagami & Ishikawa, 1972, and B. hengduanensis Williams, Ren & Xie sp. nov., plus B. perplexus), which are comparable in status to the currently accepted species of the vagans-group. Morphological corroboration of the coalescent candidate species is subtle but supports the gene coalescents if these candidates are considered near-cryptic species.

Chromosome Painting in Gymnotus carapo "Catalão" (Gymnotiformes, Teleostei): Dynamics of Chromosomal Rearrangements in Cryptic Species.

The genus Gymnotus is a large monophyletic group of freshwater weakly-electric fishes, with wide distribution in Central and South America. It has 46 valid species divided into six subgenera (Gymnotus, Tijax, Tigre, Lamontianus, Tigrinus and Pantherus) with large chromosome plasticity and diploid numbers (2n) ranging from 34 to 54. Within this rich diversity, there is controversy about whether Gymnotus (Gymnotus) carapo species is a single widespread species or a complex of cryptic species. Cytogenetic studies show different diploid numbers for G. carapo species, ranging from 40 to 54 chromosomes with varied karyotypes found even between populations sharing the same 2n. Whole chromosome painting has been used in studies on fish species and recently has been used for tracking the chromosomal evolution of Gymnotus and assisting in its cytotaxonomy. Comparative genomic mapping using chromosome painting has shown more complex rearrangements in Gymnotus carapo than shown in previous studies by classical cytogenetics. These studies demonstrate that multiple chromosome pairs are involved in its chromosomal reorganization, suggesting the presence of a complex of cryptic species due to a post zygotic barrier. In the present study, metaphase chromosomes of G. carapo occidentalis “catalão” (GCC, 2n = 40, 30m/sm+10st/a) from the Catalão Lake, Amazonas, Brazil, were hybridized with whole chromosome probes derived from the chromosomes of G. carapo (GCA, 2n = 42, 30m/sm+12st/a). The results reveal chromosome rearrangements and a high number of repetitive DNA sites. Of the 12 pairs of G. carapo chromosomes that could be individually identified (GCA 1–3, 6, 7, 9, 14, 16 and 18–21), 8 pairs (GCA 1, 2, 6, 7, 9, 14, 20, 21) had homeology conserved in GCC. Of the GCA pairs that are grouped (GCA [4, 8], [5, 17], [10, 11] and [12, 13, 15]), most kept the number of signals in GCC (GCA [5, 17], [10, 11] and [12, 13, 15]). The remaining chromosomes are rearranged in the GCC karyotype. Analysis of both populations of the G. carapo cytotypes shows extensive karyotype reorganization. Along with previous studies, this suggests that the different cytotypes analyzed here may represent different species and supports the hypothesis that G. carapo is not a single widespread species, but a group of cryptic species.

World Travelers: Parthenogenesis and Ecological Tolerance Enable Multiple Colonization Events by the Widespread Short-Tailed Whipscorpion, Stenochrus portoricensis (Schizomida: Hubbardiidae)

Abstract Whereas morphology remains a powerful tool for the diagnosis and description of short-tailed whip scorpions, or schizomids (Order Schizomida Petrunkevitch, 1945), especially when adults of both sexes are available, the systematics of some schizomid taxa is difficult to resolve due to a lack of characters in these morphologically conserved arachnids. Stenochrus portoricensis Chamberlin, 1922, defined on a single character of the female spermathecae, is the most widespread schizomid in the New World. Numerous records in the Neotropics, from the southern United States to Brazil, throughout the Caribbean, and further afield, including the Galapagos Islands and Europe, raise the question as to whether S. portoricensis is indeed a single widespread species or a complex of multiple species with conserved morphology? The present study uses a multilocus dataset and the broadest geographical sample currently available to address the phylogeography of S. portoricensis with molecular divergence dating and ancestral area reconstruction of all currently known species of Stenochrus Chamberlin, 1922. Analyses recovered S. portoricensis as paraphyletic. Two species previously synonymized are revalidated and transferred to Stenochrus. Population structure analyses recovered the remaining samples of S. portoricensis as a single monophyletic species with low genetic divergence and comprising two subclades. Ancestral area reconstruction suggests a Mesoamerican origin for Stenochrus, which contains a widespread species, recently introduced to multiple localities. Introductions to Europe and the Caribbean occurred from a single clade in the Yucatán Peninsula, Mexico, within which genetic divergence is minimal, confirming the hypothesis of multiple independent introductions with successful colonization facilitated by parthenogenetic reproduction.

Genome-Scale Data Reveal Deep Lineage Divergence and a Complex Demographic History in the Texas Horned Lizard (Phrynosoma cornutum) throughout the Southwestern and Central United States.

The southwestern and central United States serve as an ideal region to test alternative hypotheses regarding biotic diversification. Genomic data can now be combined with sophisticated computational models to quantify the impacts of paleoclimate change, geographic features, and habitat heterogeneity on spatial patterns of genetic diversity. In this study, we combine thousands of genotyping-by-sequencing (GBS) loci with mtDNA sequences (ND1) from the Texas horned lizard (Phrynosoma cornutum) to quantify relative support for different catalysts of diversification. Phylogenetic and clustering analyses of the GBS data indicate support for at least three primary populations. The spatial distribution of populations appears concordant with habitat type, with desert populations in AZ and NM showing the largest genetic divergence from the remaining populations. The mtDNA data also support a divergent desert population, but other relationships differ and suggest mtDNA introgression. Genotype–environment association with bioclimatic variables supports divergence along precipitation gradients more than along temperature gradients. Demographic analyses support a complex history, with introgression and gene flow playing an important role during diversification. Bayesian multispecies coalescent analyses with introgression (MSci) analyses also suggest that gene flow occurred between populations. Paleo-species distribution models support two southern refugia that geographically correspond to contemporary lineages. We find that divergence times are underestimated and population sizes are overestimated when introgression occurred and is ignored in coalescent analyses, and furthermore, inference of ancient introgression events and demographic history is sensitive to inclusion of a single recently admixed sample. Our analyses cannot refute the riverine barrier or glacial refugia hypotheses. Results also suggest that populations are continuing to diverge along habitat gradients. Finally, the strong evidence of admixture, gene flow, and mtDNA introgression among populations suggests that P. cornutum should be considered a single widespread species under the General Lineage Species Concept.

Genetic and morphological characterization of the freshwater mussel clubshell species complex (Pleurobema clava and Pleurobema oviforme) to inform conservation planning.

The shell morphologies of the freshwater mussel species Pleurobema clava (federally endangered) and Pleurobema oviforme (species of concern) are similar, causing considerable taxonomic confusion between the two species over the last 100 years. While P. clava was historically widespread throughout the Ohio River basin and tributaries to the lower Laurentian Great Lakes, P. oviforme was confined to the Tennessee and the upper Cumberland River basins. We used two mitochondrial DNA (mtDNA) genes, 13 novel nuclear DNA microsatellite markers, and shell morphometrics to help resolve this taxonomic confusion. Evidence for a single species was apparent in phylogenetic analyses of each mtDNA gene, revealing monophyletic relationships with minimal differentiation and shared haplotypes. Analyses of microsatellites showed significant genetic structuring, with four main genetic clusters detected, respectively, in the upper Ohio River basin, the lower Ohio River and Great Lakes, and upper Tennessee River basin, and a fourth genetic cluster, which included geographically intermediate populations in the Ohio and Tennessee river basins. While principal components analysis (PCA) of morphometric variables (i.e., length, height, width, and weight) showed significant differences in shell shape, only 3% of the variance in shell shape was explained by nominal species. Using Linear Discriminant and Random Forest (RF) analyses, correct classification rates for the two species' shell forms were 65.5% and 83.2%, respectively. Random Forest classification rates for some populations were higher; for example, for North Fork Holston (HOLS), it was >90%. While nuclear DNA and shell morphology indicate that the HOLS population is strongly differentiated, perhaps indicative of cryptic biodiversity, we consider the presence of a single widespread species the most likely biological scenario for many of the investigated populations based on our mtDNA dataset. However, additional sampling of P. oviforme populations at nuclear loci is needed to corroborate this finding.

Differentiation of South African coastal rock pool Ochthebius is associated with major ocean currents (Coleoptera: Hydraenidae)

A number of non-marine coastal invertebrate species have been found to constitute (semi-) cryptic species complexes in recent years. Here it is revealed that rather than a single widespread species, distributed from the Namibian border to the Cape south coast, South African coastal rock pool Ochthebius Leach, 1815 previously referred to Ochthebius capicola (Péringuey, 1892) comprise two distinct taxa. Ochthebius capicola (s. str.) is apparently restricted to the Benguela Ecoregion on the west coast, being replaced by Ochthebius mlamboi sp. nov., in south and east coast localities influenced by the Agulhas Current, including areas of the Eastern Cape province well outside the previous known range of these beetles. The distribution and ecology of the two species is discussed, with reference to biogeographic breaks in southern African coastal taxa, and the emerging view that many ‘widespread’ coastal rock pool Ochthebius may actually be (semi-) cryptic species complexes.

Speciation and secondary contact in a fossorial island endemic, the São Tomé caecilian.

A period of isolation in allopatry typically precedes local adaptation and subsequent divergence among lineages. Alternatively, locally adapted phenotypes may arise and persist in the face of gene flow, resulting in strong correlations between ecologically-relevant phenotypic variation and corresponding environmental gradients. Quantifying genetic, ecological, and phenotypic divergence in such lineages can provide insights into the abiotic and biotic mechanisms that structure populations and drive the accumulation of phenotypic and taxonomic diversity. Low-vagility organisms whose distributions span ephemeral geographic barriers present the ideal evolutionary context within which to address these questions. Here, we combine genetic (mtDNA and genome-wide SNPs) and phenotypic data to investigate the divergence history of caecilians (Amphibia: Gymnophiona) endemic to the oceanic island of São Tomé in the Gulf of Guinea archipelago. Consistent with a previous mtDNA study, we find two phenotypically and genetically distinct lineages that occur along a north-to-south axis with extensive admixture in the centre of the island. Demographic modelling supports divergence in allopatry (~300kya) followed by secondary contact (~95kya). Consequently, in contrast to a morphological study that interpreted latitudinal phenotypic variation in these caecilians as a cline within a single widespread species, our analyses suggest a history of allopatric lineage divergence and subsequent hybridization that may have blurred species boundaries. We propose that late Pleistocene volcanic activity favoured allopatric divergence between these lineages with local adaptation to climate maintaining a stable hybrid zone in the centre of São Tomé Island. Our study joins a growing number of systems demonstrating lineage divergence on volcanic islands with stark environmental transitions across small geographic distances.

Diversification Pattern of the Widespread Holarctic Cuckoo Bumble Bee,Bombus flavidus(Hymenoptera: Apidae): The East Side Story

AbstractRecent bumble bee declines have made it increasingly important to resolve the status of contentious species for conservation purposes. Some of the taxa found to be threatened are the often rare socially parasitic bumble bees. Among these, the socially parasitic bumble bee, Bombus flavidus Eversmann, has uncertain species status. Although multiple separate species allied with B. flavidus have been suggested, until recently, recognition of two species, a Nearctic Bombus fernaldae (Franklin) and Palearctic B. flavidus, was favored. Limited genetic data, however, suggested that even these could be a single widespread species. We addressed the species status of this lineage using an integrative taxonomic approach, combining cytochrome oxidase I (COI) and nuclear sequencing, wing morphometrics, and secretions used for mate attraction, and explored patterns of color polymorphism that have previously confounded taxonomy in this lineage. Our results support the conspecificity of fernaldae and flavidus; however, we revealed a distinct population within this broader species confined to eastern North America. This makes the distribution of the social parasite B. flavidus the broadest of any bumble bee, broader than the known distribution of any nonparasitic bumble bee species. Color polymorphisms are retained across the range of the species, but may be influenced by local mimicry complexes. Following these results, B. flavidusEversmann, 1852 is synonymized with Bombus fernaldae (Franklin, 1911) syn. nov. and a subspecific status, Bombus flavidus appalachiensisssp. nov., is assigned to the lineage ranging from the Appalachians to the eastern boreal regions of the United States and far southeastern Canada.

The global freshwater bivalve checklist’s extension: Freshwater occurrences and phylogenetic position of Galatea clams from West Africa (Venerida: Donacidae)

The bivalve genus Galatea Bruguière, 1797 (Venerida: Donacidae) was thought to contain exclusively brackish-water clams, the ranges of which are confined to estuaries and lower tidal parts of large rivers in West Africa. This genus was therefore included to the global freshwater bivalve checklists (Bogan 2013; Graf 2013) as a largely estuarine group. Conversely, a review of published data alongside our field surveys indicate that at least three populations of Galatea spp. largely occur in freshwater environment, i.e. those from the Sanaga (Cameroon), Niger (Nigeria), and Volta (Ghana) rivers. The systematic placement of these populations is unclear, as are the taxonomic status and validity of numerous nominal taxa described in this genus from a variety of localities throughout the Atlantic Coast of Africa (Angola to Senegal). We tentatively assign the populations from Niger and Volta to Galatea paradoxa (Born, 1778), while the Sanaga’s population is considered here as Galatea schwabi (Clench, 1929). However, these taxa do not share clear morphological differences and may belong to a single widespread species. In this study, we present the first DNA sequence data for a Galatea member, i.e. G. schwabi. Our COI phylogeny supports its placement within the family Donacidae suggesting sister relationships between Galatea and Donax Linnaeus, 1758. Most Galatea populations play a vital role for local riparian communities in West Africa as an intensively exploited food source. Furthermore, the clams are heavily threaten by anthropogenic impacts such as dam construction, riverbed substrate mining, and river pollution. The fishing loads and habitat degradation altogether lead to the rapid decreasing of Galatea populations in several water bodies, e.g. the Volta River in Ghana. It is impossible to develop conservation and management plans for these clams due to the lack of reliable species-level taxonomic concept of the genus. It is clear that the Galatea taxonomy and ecology need a thorough revision in the future based on DNA sequences of newly collected samples from all West African rivers, in which these remarkable clams occur.

Biogeography and integrative taxonomy of Epipterygium (Mniaceae, Bryophyta)

AbstractA significant number of bryophyte species are thought to have transcontinental geographic ranges, often with multiple disjunct distribution areas. One of these cases is Epipterygium tozeri (Mniaceae), with a Holarctic distribution and disjunct ranges in western North America, the Mediterranean, Japan and central Asia. Collections from different geographic regions were lumped into E. tozeri based on morphology, but a molecular confirmation was lacking so far. Here, we tested species concepts in the genus Epipterygium, with a special focus on the E. tozeri species complex, combining morphological and DNA sequence data for the nuclear ribosomal ITS region and two plastid loci (trnG intron, trnT‐psbD spacer). In a second step, we reconstructed the historical biogeography of the genus. We found that Epipterygium most likely originated in Asia or North/Central America and that the alleged single widespread species E. tozeri with disjunct ranges is in fact a group of genetically and morphologically distinct taxa, including four overlooked species, for which we provide descriptions: E. atlanticum sp. nov., E. biauritum sp. nov., E. oreophilum sp. nov., and E. yunnanense sp. nov. The biogeographical history of these species is best explained by a step‐wise parallel colonization of the Eurasian and American continents followed by in‐situ speciation.

One species, two developmental modes: a case of geographic poecilogony in marine gastropods

BackgroundPoecilogony, the presence of two developmental modes in the same animal species, is a rare phenomenon. Few cases of poecilogony have been suggested for marine invertebrates including molluscs and even less stood extensive testing, mostly revealing a species pair with differing developmental modes. We studied a textbook example of poecilogony in the viviparous snail Planaxis sulcatus (Gastropoda: Planaxidae), for the first time throughout its entire distribution range.ResultsIn the Western Indian Ocean and Red Sea this intertidal species is observed to have large, shelled juveniles, whereas in the Indo-West Pacific planktotrophic veliger larvae are released from a subhaemocoelic brood pouch. We uncovered a shift in developmental modes across its range: from west to east successively earlier developmental stages are released. Furthermore, genetic data based on mitochondrial DNA suggests to recognize P. sulcatus as a single species rather than a group of cryptic species. A reconstruction of the ancestral area of P. sulcatus based on molecular data outlines the Western Indian Ocean and the Indo-West Pacific as area of origin.ConclusionThe findings supporting Planaxis sulcatus as a single widespread species and the geographical shift from one reproductive mode to another suggest for this species to truly represent a case of geographic poecilogony, i.e. differing developmental modes between populations of the same species. Furthermore, the results of our ancestral range estimation imply the release of planktotrophic larvae as the ancestral developmental mode.

Modern cryptic species and crocodylian diversity in the fossil record

AbstractAdvances in molecular biology and genetics are revealing that many recognized crocodylian species are complexes of two or more cryptic species. These discoveries will have a profound impact on interpretation of the crocodyliform fossil record. Our understanding of ranges of intraspecific variation in modern crocodylian morphology may be based on multiple species and thus express both intraspecific and interspecific variation. This raises questions about our ability to recognize modern species in the fossil record, and it also indicates that specimens from disparate localities or horizons may represent not single widespread species, but multiple related species. Ranges of variation in modern species require a thorough re-evaluation, and we may have to revisit previous perceptions of past crocodyliform diversity, rates of evolution or anagenetic lineages in stratigraphic succession. These challenges will not be unique to those studying crocodyliforms and will require sophisticated approaches to variation among modern and fossil specimens.

Phylogeography of the widespread Caribbean spiny orb weaver Gasteracantha cancriformis.

BackgroundModern molecular analyses are often inconsistent with pre-cladistic taxonomic hypotheses, frequently indicating higher richness than morphological taxonomy estimates. Among Caribbean spiders, widespread species are relatively few compared to the prevalence of single island endemics. The taxonomic hypothesis Gasteracantha cancriformis circumscribes a species with profuse variation in size, color and body form. Distributed throughout the Neotropics, G. cancriformis is the only morphological species of Gasteracantha in the New World in this globally distributed genus.MethodsWe inferred phylogenetic relationships across Neotropical populations of Gasteracantha using three target genes. Within the Caribbean, we estimated genetic diversity, population structure, and gene flow among island populations.ResultsOur findings revealed a single widespread species of Gasteracantha throughout the Caribbean, G. cancriformis, while suggesting two recently divergent mainland populations that may represent separate species, diverging linages, or geographically isolated demes. The concatenated and COI (Cytochrome c oxidase subunit 1) phylogeny supported a Caribbean clade nested within the New World. Genetic variability was high between island populations for our COI dataset; however, gene flow was also high, especially between large, adjacent islands. We found structured genetic and morphological variation within G. cancriformis island populations; however, this variation does not reflect genealogical relationships. Rather, isolation by distance and local morphological adaptation may explain the observed variation.

Geodina (Pezizomycetes: Wynneaceae) has a single widespread species in tropical America.

Geodina salmonicolor is shown to be a synonym of G. guanacastensis, the type and only species of the genus. Comparisons of ITS rDNA sequences of a paratype and two recent collections of G. guanacastensis with published ITS sequences of G. salmonicolor, from the Dominican Republic, show that these are nearly identical. When G. salmonicolor was erected no sequences of the type species were available. Morphological comparisons supports the conspecificity. Details regarding the description of G. salmonicolor are pointed out. A four-gene phylogeny places Geodina and Wynnea as a supported sister group to the rest of the Sarcoscyphaceae. Species in these genera share morphological traits of cyanophobic spore markings, dark angular outer excipular cells that give rise to hairs and the origin of several apothecia from a common basal stalk. Their occurrence on soil rather than on wood or plant material distinguish them from other Sarcoscyphaceae. Based on morphology, phylogenic relationships and trophic interactions we erect a new family, Wynneaceae, for Geodina and Wynnea.

Cytochrome Oxidase I Sequences from Northern and Southern California Suggest Cryptic Baetis (Ephemeroptera: Baetidae) Species

The geographically widespread mayfly genus Baetis occurs from the subarctic to tropical regions of the world. Many of the 20 described Baetis species in North America are known to show cryptic species diversity. However, studies of Baetis that have examined morphology and genetic diversity have found mixed results in terms of cryptic species, with some studies indicating a complex of related species and others suggesting a single widespread species. We used Bayesian analyses, intra- and interspecific genetic diversity values, and median-joining haplotype networks to compare cytochrome oxidase I (COI) sequences from Baetis specimens from parts of northern and southern California (n = 742). Our results suggest that genetic diversity at the COI gene region in populations from northern California supports the diversity indicated by morphology (Baetis tricaudatus and Baetis adonis); however, populations in southern California exhibit more genetic diversity than indicated by morphology alone (DNA divergence > 1%), which suggests cryptic species diversity. The putative species that was morphologically and genetically identified as Baetis tricaudatus was the only taxon that occurred in both regions. No haplotypes were shared between regions. Intraspecific diversity within putative species from northern California was >1%. In contrast, intraspecific diversity within species from southern California was always <1%. Such discrepancies highlight the need for locally derived reference libraries in using next-generation sequencing or environmental DNA as a method to examine genetic diversity.