Speciation in Darwin's darklings: taxonomy and evolution of Stomion beetles in the Galápagos Islands, Ecuador (Insecta: Coleoptera: Tenebrionidae)

Stomion is one of three speciose and taxonomically difficult genera of flightless Darwin's darkling beetles of the Galápagos Islands. The previously named species and subspecies of Stomion are analysed by morphometric and cladistic methods. Eleven species are here recognized, which probably descended from colonization by a single ancestral species. Cladistic analysis yielded two weakly supported clades that are different from previously published morphological and allozyme genotype groups. Phenotypic and genotypic characters may be evolving independently. There is much within-species variation, but there is no compelling evidence of adaptive radiation in Stomion , in contrast to that in the famous Darwin's finches. The analyses show the need for changes in morpho-species taxonomy: S. punctipennis Van Dyke ( syn. nov. ) is elevated to full species from a subspecies of S. galapagoensis Waterhouse. There is no evidence to support the validity of: S. laevigatum santacruzensi Franz ( syn. nov. ), synonomized here under S. l. laevigatum Waterhouse; S. galapagoensis leleupi Kaszab ( syn. nov. ), synonomized here under S. linelli Blair; S. galapagoensis pinzoni Franz ( syn. nov. ), synonomized here under S. obesum Van Dyke. S. genovesa sp. nov. is described from Genovesa Island. Lectotypes are designated for S. galapagoensis Waterhouse, S. laevigatum Waterhouse and S. helopoides Waterhouse .   © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 135–152.     

Description of a new species of Ectinorus (E. spiculatus) (Siphonaptera, Rhopalopsyllidae) from Argentina and a review of the subgenus Ichyonus Smit, 1987

A new species, Ectinorus spiculatus, is described from Phyllotis xanthopygus (Waterhouse) and Akodon iniscatus Thomas from Neuquén Province, Argentina. Habitat characteristics are presented for the type locality. A change in status of four additional subspecies of the Ectinorus subgenus Ichyonus Smit is provided. Ectinorus onychius onychius Jordan and Rothschild, Ectinorus onychius deplexus Smit and Ectinorus onychius angularis Smit & Rosicky were elevated to specific status. Ectinorus (Ichyonus) onychius fueginus was relegated as a junior synonym of the nominate species. Phyllotis xanthopygus, Abrothrix olivaceus xanthorhinus, Loxodontomys micropus Waterhouse, and Euneomys chinchilloides (Waterhouse) are new host records for Ectinorus onychius. A key to the three species of Ichyonus is included.     

Molecular phylogeny of the tribe Candalidini (Lepidoptera: Lycaenidae): systematics,diversification and evolutionary history

The butterfly tribe Candalidini is geographically restricted to Australia and mainland New Guinea and its adjacent islands. With 60 species and subspecies, it represents a large radiation of Papilionoidea in the Australian region. Although the species-level taxonomy is relatively well understood, the number of genera is uncertain, varying from two to eight. We reconstructed the phylogeny of the Candalidini based on a 13-locus hybrid enrichment probe set (12.8 Kbp: COI, Thiolase, CAD, CAT, DDC, EF1-a, GAPDH, HCL, IDH, MDH, RPS2, RPS5, Wingless), including all previously recognized genera and 76% (28/37) of the species-level diversity of the tribe. Maximum likelihood analysis recovered the Candalidini as a strongly supported monophyletic group. In conjunction with morphological characters, the phylogeny provided a robust framework for a revised classification in which we recognize four genera, 37 species and 23 subspecies. The genus Nesolycaena Waterhouse & R.E. Turner is considered in synonymy with Candalides Hübner, and four other genera are not recognized, namely, Holochila C. Felder, Adaluma Tindale, Zetona Waterhouse and Microscena Tite. Of the four valid genera, the absimilis group (23 species) is placed in the newly described genus Eirmocides Braby, Espeland & Müller gen. nov. (type species Candalides consimilis Waterhouse). The erinus group (six species) is assigned to Erina Swainson, which is reinstated. Chrysophanus cyprotus Olliff is assigned to Cyprotides Tite, which is also reinstated as a monotypic genus. The remaining seven species are placed in Candalides sensu stricto. Overall, we propose 47 new nomenclatural changes at the species and subspecies levels, including the synonymy of Holochila biaka Tite as Eirmocides tringa biaka (Tite) syn. nov. et comb. nov. and recognition of Candalides hyacinthinus gilesi M.R. Williams & Bollam as a distinct species Erina gilesi (M.R. Williams & Bollam stat. rev. et comb. nov. A dated phylogeny using Bayesian inference in BEAST2 and biogeographical and habitat analyses based on the DEC model in BioGeoBEARS indicated that the ancestor of the Candalidini most likely evolved in rainforest habitats of the mesic biome in situ on the Australian plate of Southern Gondwana during the Eocene (c. 43 Ma). A major period of diversification occurred in the Miocene, which coincided with aridification of the Australian continent, followed by a further episode of radiation in montane New Guinea during the Plio-Pleistocene. This published work has been registered on ZooBank by the authors: Michael Braby: http://zoobank.org/urn:lsid:zoobank.org:author:4D3A7605-EBD0-40F6-A5F2-7F67F59E3D60 ; Marianne Espeland: http://zoobank.org/urn:lsid:zoobank.org:author:00D6F9F9-3902-4A8B-846F-720AB32922A6 ; Chris Müller: http://zoobank.org/urn:lsid:zoobank.org:author:15FE5F26-7596-46C2-9697-1FD92A692D0D ; http://zoobank.org/urn:lsid:zoobank.org:pub:47D5CA34-C294-4FBD-84B6-1C2A82B7CADF .     

Uacaries,new world monkeys of the genus Cacajao(Cebidae,Platyrrhini): A preliminary taxonomic review with the description of a new subspecies

The two known species of uacaries, inhabitants of the upper Amazonian region, are the black head Cacajao melanocephalus with subspecies C. m. melanocephalus Humboldt and C. m. ouakary Spix, and the larger bald head uacari C. calvus with subspecies C. c. ucayalii Thomas, C. c. rubicundus I. Geoffroy and Deville, C. c. calvus I. Geoffroy, and C. c. novaesi described as new. The diagnostic generic characters described are the external, cranial, dental, some postcranial, and cytogenetic. The species are described and compared and their geographic distribution plotted with those of their subspecies delimited. Sexual differences are outlined. Apart from size-related characters, the species and subspecies are distinguished by pelage pattern of head and coloration in general. It is shown that both species could have diverged from a hairy-headed melanistic ancestral form. Pelage divergence in the descendants was expressed by the more pilose head of C. melanocephalus, and less pilose of C. calvus. Coloration differentiation was geographic and followed metachromic lines with mutation from eumelanism to partial pheomelanism (reddish or golden) in C. melanocephalus and to virtually complete pheomelanism in C. calvus. The subspecies of each species are distinguished by color patterns resulting from selective bleaching or dilution of the pheomelanin fields. The most saturate pheomelanic subspecies of C. calvus is C. c. ucayalii and the most dilute is the albinotic C. c. calvus. Correlation between coloration and environment is not evident. A gazetteer identifies all locality records plotted by numbers on the geographic distribution maps.     

Phylogenetic relationships among A-genome species of the genus Oryza revealed by intron sequences of four nuclear genes

The A-genome group in Oryza consists of eight diploid species and is distributed world-wide. Here we reconstructed the phylogeny among the A-genome species based on sequences of nuclear genes and MITE (miniature inverted-repeat transposable elements) insertions. Thirty-seven accessions representing two cultivated and six wild species from the A-genome group were sampled. Introns of four nuclear single-copy genes on different chromosomes were sequenced and analysed by both maximum parsimony (MP) and Bayesian inference methods. All the species except for Oryza rufipogon and Oryza nivara formed a monophyletic group and the Australian endemic Oryza meridionalis was the earliest divergent lineage. Two subspecies of Oryza sativa (ssp. indica and ssp. japonica) formed two separate monophyletic groups, suggestive of their polyphyletic origin. Based on molecular clock approach, we estimated that the divergence of the A-genome group occurred c. 2.0 million years ago (mya) while the two subspecies (indica and japonica) separated c. 0.4 mya. Intron sequences of nuclear genes provide sufficient resolution and are informative for phylogenetic inference at lower taxonomic levels.     

Molecular phylogenetics of a South Pacific sap beetle species complex (Carpophilus spp., Coleoptera: Nitidulidae)

Several species of sap beetles in the genus Carpophilus are minor pests of fresh produce and stored products, and are frequently intercepted in biosecurity operations. In the South Pacific region, the superficially similar species C. maculatus and C. oculatus are frequently encountered in these situations. Three subspecies of C. oculatus have been described, and the complex of these four taxa has led to inaccurate identification and questions regarding the validity of these taxa. A molecular phylogenetic study using the mitochondrial gene cytochrome c oxidase I (COI) and two nuclear markers comprising the rDNA internal transcribed spacer 2 (ITS2) and the D1-D2 region of the large (28S) ribosomal RNA subunit showed that C. maculatus, and C. o. cheesmani were easily differentiated from the two other subspecies of C. oculatus. COI also showed differentiation between C. o. gilloglyi and C. o. oculatus, but this was not shown when third codon positions were removed and when RY-coding analyses were conducted. Generalised mixed Yule-Coalescent (GMYC) models were fitted to trees estimated from the COI data and were analysed using a multimodel approach to consider the evidence for three taxonomic groupings of the C. oculatus group. While the arrangement with the highest cumulative weight was not the arrangement ultimately accepted, the accepted taxonomy also had an acceptable level of support. ITS2 showed structure within C. oculatus, however C. o. oculatus was resolved as paraphyletic with respect to C. o. gilloglyi. COI showed evidence of sequence saturation and did not adequately resolve higher relationships between species represented in the dataset. 28S resolved higher relationships, but did not perform well at the species level. This study supports the validity of C. maculatus as a separate species, and provides sufficient evidence to raise C. o. cheesmani to the level of species. This study also shows significant structure within and between C. o. gilloglyi and C. o. oculatus, giving an indication of recent speciation events occurring. To highlight the interesting biology between these two taxa, C. o. gilloglyi is retained as a subspecies of C. oculatus. These results give clarity regarding the taxonomic status of C. maculatus and the subspecies of C. oculatus and provide a platform for future systematic research on Carpophilus.     

Molecular phylogeny of treecreepers (Certhia) detects hidden diversity†

We sequenced a part of the mitochondrial cytochrome-b gene from the seven treecreeper species, including 18 subspecies, to reconstruct the phylogeny of the genus Certhia . Species status of all seven species could be affirmed. Certhia discolor , C. himalayana , C . nipalensis , and C . tianquanensis , the species with relatively small distribution ranges in southeast Asia and simple territorial song, are found at the base of all phylogenetic trees, although without good support. A comparatively recent sister species of C. tianquanensis is C. nipalensis , replacing C. discolor as closest relative. Certhia familiaris , C. brachydactyla and C. americana form a derived set of species (again only weak support). The closest relative of C. americana is C. brachydactyla . The C. familiaris subtree is deeply split into two well-defined population groups: a Eurasian group including populations in northern China (Qinling range northward and all Eurasia) and a Sino-Himalayan group (Himalayas and China excluding northern China). In accordance with acoustic characters, the three subspecies hodgsoni , mandellii and khamensis of the Sino-Himalayan group are combined and elevated to species rank: Certhia hodgsoni . Certhia discolor manipurensis is deeply split from nominate discolor as well, and is also promoted to species level. Within C. brachydactyla (western palearctic) and within C. hodgsoni (Himalayas, China) several populations form well-supported separate lineages that diverged quite recently and represent subspecies level. In all other species, molecular–genetic and vocal characters support traditional species delimitation.     

A revision of the genus Homoeogenus Waterhouse with notes on the immature stages of H.laurae sp.n. (Coleoptera: Psephenidae: Eubriinae)

Abstract. The genus Homoeogenus Waterhouse is revised. H.punctatum Waterhouse is redescribed, and two new species, H.chinensis sp.n. (Szechuan) and H.laurae sp.n. (Taiwan), are described. The morphology of the immature stages and the ecology of H.laurae are described. A key to the Oriental genera of Eubriinae is included.     

Inferring species-level phylogenies and taxonomic distinctiveness using multilocus data in Sistrurus rattlesnakes

Phylogenetic relationships and taxonomic distinctiveness of closely related species and subspecies are most accurately inferred from data derived from multiple independent loci. Here, we apply several approaches for understanding species-level relationships using data from 18 nuclear DNA loci and 1 mitochondrial DNA locus within currently described species and subspecies of Sistrurus rattlesnakes. Collectively, these methods provide evidence that a currently described species, the massasauga rattlesnake (Sistrurus catenatus), consists of two well-supported clades, one composed of the two western subspecies (S. c. tergeminus and S. c. edwardsii) and the other the eastern subspecies (S. c. catenatus). Within pigmy rattlesnakes (S. miliarius), however, there is not strong support across methods for any particular grouping at the subspecific level. Monophyly based tests for taxonomic distinctiveness show evidence for distinctiveness of all subspecies but this support is strongest by far for the S. c. catenatus clade. Because support for the distinctiveness of S. c. catenatus is both strong and consistent across methods, and due to its morphological distinctiveness and allopatric distribution, we suggest that this subspecies be elevated to full species status, which has significant conservation implications. Finally, most divergence time estimates based upon a fossil-calibrated species tree are > 50% younger than those from a concatenated gene tree analysis and suggest that an active period of speciation within Sistrurus occurred within the late Pliocene/Pleistocene eras.     

A CLADISTIC ANALYSIS OF CIRCAEA (ONAGRACEAE)

Abstract— Circaea (Onagraceae), a genus of seven species from the northern hemisphere, forms a monophylctic group defined by the following synapomorphies: two stamens (opposite the sepals), fruits indehiscent capsules, hooked hairs on the fruits, and perianth parts reduced to two. A cladistic analysis of the genus was performed using 22 characters from morphology, anatomy and palynology. The seven species and seven additional subspecies were considered the terminal taxa. Polarity of the characters is based on the outgroup comparison method. Eighteen equally parsimonious cladograms were produced, each with 32 steps and a consistency index of 0.75. A successive weighting procedure was applied, resulting in six cladograms with a consistency index of 0.95. All 24 cladograms share the following seven monophylctic groups: (1) all species except C. cordala and C. glabrescens (stipules deciduous); (2) the group of C. mollis , the three subspecies of C. lutetiana and C. erubescens (exsertcd nectary); (3) C. repens and all six subspecies of C. alpina (single-seeded fruits, stolons terminated by tubers, and viscin threads reduced or absent); (4) the six subspecies of C. alpina (unilocular ovaries with no trace of a second loculc and tardily opening perianth); (5) C. alpina subspecies alpina, micrantha, pacifica , and imaicola (flowers opening on ascending to erect pedicels); (6) C. alpina subspecies alpina, micrantha , and pacifica (translucent leaves); (7) C. alpina subspecies alpina and murantha (glabrous stems). Results of the cladistic analysis support most of the current systematic classification of the genus, except for the relationships among the three subspecies of C. lutetiana .     

Molecular systematics of the western rattlesnake, Crotalus viridis (Viperidae), with comments on the utility of the D-loop in phylogenetic studies of snakes.

Crotalus viridis, the western rattlesnake, ranges throughout western North America and has been divided into at least eight subspecies. However, the validity of and relationships among these subspecies and the monophyly of C. viridis as a whole are questionable. We used mitochondrial DNA sequence data from the D-loop region and ND2 gene to examine the relationships among 26 populations of C. viridis and to test the monophyly of this species. These data were analyzed separately and combined using maximum-likelihood and maximum-parsimony. The C. viridis group was monophyletic in all combined analyses, consisting of two strongly divergent clades. We recommend that these clades be recognized as two distinct evolutionary species: C. viridis and C. oreganus. Crotalus viridis should be restricted to the subspecies viridis and nuntius and the remaining subspecies be assigned to the species C. oreganus. Our data do not allow strong evaluation of the validity of the subspecies. We found that the ND2 gene had greater sequence divergences among closely related individuals than the D-loop region, but this relationship reversed at higher levels of divergence. This pattern is apparently due to: (1) ND2 third positions evolving faster than the D-loop but becoming saturated at higher levels of divergence, and (2) the D-loop evolving faster than ND2 second (and possibly first) positions. Our results suggest that the ND2 gene is preferable for examining intraspecific relationships and the D-loop may better resolve relationships between species of snakes. The latter result is contrary to the common perception of the phylogenetic utility of the D-loop. Another unusual result is that the 145 bp spacer region, adjacent to the 5' end of the light strand of the D-loop, provides greater phylogenetic resolution than the 1030 bp D-loop.     

A review of the primary types of the Hawaiian stag beetle genus Apterocyclus Waterhouse (Coleoptera,Lucanidae, Lucaninae), with the description of a new species

The species of the Hawaiian stag beetle genus Apterocyclus Waterhouse (Coleoptera: Lucanidae) are reviewed following an examination of all primary types. Although the continued existence of the species is unknown and some possibly are extinct there are five recently extant species, including one species that is described here as new. The holotypes for all available names are pictured, and synonymies discussed and updated. Lectotypes are designated for Apterocyclus honoluluensis Waterhouse and A. munroi Sharp. A key to species and a revised catalog for the genus are provided.     

中国桃花水母属的修订(淡水水母目,笠水母科)

作者对我国的桃花水母属Craspedacusta的2亚种和2变种重新通过形态学观察,并与国内外已发表的Craspeda-custa属7种相比较,其刺丝囊疣的形状和排列及生殖腺的形状和颜色均存在明显的差异.故认为此2亚种和2变种应提升为种,即信阳桃花水母Craspedacusta xinyangensis He,1980,杭州桃花水母Craspedacusta hangzhouensis He,1980、乐山桃花水母Craspedacusta kiatingi Gaw and Kung,1939和宜昌桃花水母Craspedacusta kawaii(Oka,1907).本文将全世界11种桃花水母的形态特征作了比较并附以系统检索.     

Fuzzy Boundaries: Color and Gene Flow Patterns among Parapatric Lineages of the Western Shovel-Nosed Snake and Taxonomic Implication

Accurate delineation of lineage diversity is increasingly important, as species distributions are becoming more reduced and threatened. During the last century, the subspecies category was often used to denote phenotypic variation within a species range and to provide a framework for understanding lineage differentiation, often considered incipient speciation. While this category has largely fallen into disuse, previously recognized subspecies often serve as important units for conservation policy and management when other information is lacking. In this study, we evaluated phenotypic subspecies hypotheses within shovel-nosed snakes on the basis of genetic data and considered how evolutionary processes such as gene flow influenced possible incongruence between phenotypic and genetic patterns. We used both traditional phylogenetic and Bayesian clustering analyses to infer range-wide genetic structure and spatially explicit analyses to detect possible boundary locations of lineage contact. Multilocus analyses supported three historically isolated groups with low to moderate levels of contemporary gene exchange. Genetic data did not support phenotypic subspecies as exclusive groups, and we detected patterns of discordance in areas where three subspecies are presumed to be in contact. Based on genetic and phenotypic evidence, we suggested that species-level diversity is underestimated in this group and we proposed that two species be recognized, Chionactis occipitalis and C. annulata. In addition, we recommend retention of two subspecific designations within C. annulata (C. a. annulata and C. a. klauberi) that reflect regional shifts in both genetic and phenotypic variation within the species. Our results highlight the difficultly in validating taxonomic boundaries within lineages that are evolving under a time-dependent, continuous process.     

Mitochondrial sequence diversity within a subspecies of savanna monkeys (Cercopithecus aethiops) is similar to that between subspecies

Cercopithecus aethiops can be classified into four subspecies by morphology and by geographic distribution. However, the phylogenetic relationship between these subspecies is unclear. We previously found five distinct haplogroups of mitochondrial DNA (mtDNA) in the subspecies C. aethiops aethiops at the restriction fragment length polymorphism (RFLP) level, and found that those haplogroups are parapatrically distributed in their habitat. To determine the relationship between subspeciation and haplogroup formation in a subspecies, we compared mtDNA control region and 12S rRNA gene sequences (approximately 700 bp) in C. a. aethiops, two other subspecies of C. aethiops, and two species of Cercopithecus: The diversity between haplogroups in C. a. aethiops was almost the same as that between subspecies. This similar level of diversification between and within haplogroups may explain why a previously obtained mtDNA tree did not show monophyletic branching according to subspecies.     

Speciation in the sub-Antarctic weevil genus Dusmoecetes Jeannel (Coleoptera: Curculionidae)

Relatively few instances of sympatric speciation have been reported in the literature, and both theoretical and empirical studies of this mode of speciation remain controversial. Recently, a model of sympatric speciation less restrictive than earlier ones has been proposed. This study presents a hypothetical speciation scenario, based on current observations, which seems to be consistent with the new model. Two morphologically similar, though ecologically separated, species are identified in the Dusmoecetes similis (C. O. Waterhouse) species complex on Marion Island (46° 54'S, 37° 45'E), based on a study of the morphology, biology and ecology of the group. Differences between the demands placed on angiosperm- and bryophyte-feeding members of the complex, and the differing demands of bryophyte and angiosperm-dominated communities, coupled with low vagility and a high degree of assortative mating, suggest that a sympatric model can be used to explain speciation in this genus, which probably occurred within the last 10,000 years. Differences between Dusmoecetes marioni Jeannel and D. Similis (Waterhouse) are discussed, and a lectotype designated for the latter species.     

A TAXONOMIC STUDY ON COENOSIA TIGRINA SPECIES-GROUP(DIPTERA: MUSCIDAE) IN CHINA

The Chinese species of Coenosia tigrina species ‐ group of the genus Coenosia Meigen, 1826 are treated. One new species, C. albisquama sp. nov., and two new subspecies, C. attenuata brunnea subsp. nov. and C. strigipes bannaensis subsp. nov., are described. A key to Chinese species is given to seperate the species. The types specimens are deposited in the Institute of Entomology, Shenyang Normal University.