Integration of molecular, ecological, morphological and endosymbiont data for species delimitation within the Pnigalio soemius complex (Hymenoptera: Eulophidae)

Integrative taxonomy is a recently developed approach that uses multiple lines of evidence such as molecular, morphological, ecological and geographical data to test species limits, and it stands as one of the most promising approaches to species delimitation in taxonomically difficult groups. The Pnigalio soemius complex (Hymenoptera: Eulophidae) represents an interesting taxonomical and ecological study case, as it is characterized by a lack of informative morphological characters, deep mitochondrial divergence, and is susceptible to infection by parthenogenesis‐inducing Rickettsia. We tested the effectiveness of an integrative taxonomy approach in delimiting species within the P. soemius complex. We analysed two molecular markers (COI and ITS2) using different methods, performed multivariate analysis on morphometric data and exploited ecological data such as host–plant system associations, geographical separation, and the prevalence, type and effects of endosymbiont infection. The challenge of resolving different levels of resolution in the data was met by setting up a formal procedure of data integration within and between conflicting independent lines of evidence. An iterative corroboration process of multiple sources of data eventually indicated the existence of several cryptic species that can be treated as stable taxonomic hypotheses. Furthermore, the integrative approach confirmed a trend towards host specificity within the presumed polyphagous P. soemius and suggested that Rickettsia could have played a major role in the reproductive isolation and genetic diversification of at least two species.     

Risks associated with introduction of poeciliids for control of mosquito larvae: first record of the non‐native Gambusia holbrooki in Argentina

This study confirms the presence of two species of the non‐native mosquitofish Gambusia in Argentina. The risks that they represent to native biota, their potential dispersal in the region, and their effectiveness in mosquito larvae control are discussed.     

Three new species of Stiphrornis (Aves: Muscicapidae) from the Afro-tropics,with a molecular phylogenetic assessment of the genus

We describe three new species of forest robin in the genus Stiphrornis; two from West Africa and one from the Congo Basin. Each species represents a distinct phylogenetic lineage based on genetic analysis. In addition to genetic differentiation, each new species is diagnosable from other Stiphrornis lineages by morphology, and by plumage. One of the new species appears to be restricted to the Central and Brong-Ahafo Regions of Ghana, and another is restricted to Benin and the Central Region of Ghana. In Ghana, these two new species presumably come into contact with Stiphrornis erythrothorax (Western Region of Ghana and westward), and there is evidence that one of the new species has a distinguishably different song from erythrothorax. The distribution of the third new species is primarily on the south bank of the Congo River, near the city of Kisangani. Recognition of these species provides additional evidence that Afrotropical forests are harbouring substantial cryptic diversity, and that our knowledge of the drivers of this diversity remains poorly documented across the region.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:BF2A0BE6-1140-4EFF-9035-380D61AB03AE     

New species of Thinobius Kiesenwetter, 1844 (Coleoptera: Staphylinidae) from Argentina with ecological notes

Thinobius andinus sp. nov. from Argentina is described and illustrated, detailed information on its ecology is provided and a key to species of Thinobius from south-western South America is given. This species was collected from high elevation stream areas of the Mendoza River watershed. It belongs to pollution-sensitive species, and it was mainly found in clear, low-salinity cold waters pertaining to high elevation streams with riparian vegetation. Lectotype is designated for Thinobius pulchripennis Bernhauer, 1923.     

Testing concordance in species boundaries using acoustic,morphological, and molecular data in the field cricket genus Itaropsis (Orthoptera: Grylloidea,Gryllidae: Gryllinae)

In most taxa, species boundaries are inferred based on differences in morphology or DNA sequences revealed by taxonomic or phylogenetic analyses. In crickets, acoustic mating signals or calling songs have species‐specific structures and provide a third data set to infer species boundaries. We examined the concordance in species boundaries obtained using acoustic, morphological, and molecular data sets in the field cricket genus Itaropsis. This genus is currently described by only one valid species, Itaropsis tenella, with a broad distribution in western peninsular India and Sri Lanka. Calling songs of males sampled from four sites in peninsular India exhibited significant differences in a number of call features, suggesting the existence of multiple species. Cluster analysis of the acoustic data, molecular phylogenetic analyses, and phylogenetic analyses combining all data sets suggested the existence of three clades. Whatever the differences in calling signals, no full congruence was obtained between all the data sets, even though the resultant lineages were largely concordant with the acoustic clusters. The genus Itaropsis could thus be represented by three morphologically cryptic incipient species in peninsular India; their distributions are congruent with usual patterns of endemism in the Western Ghats, India. Song evolution is analysed through the divergence in syllable period, syllable and call duration, and dominant frequency. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 285–303.     

Pallenopsis patagonica (Hoek, 1881) – a species complex revealed by morphology and DNA barcoding,with description of a new species of Pallenopsis Wilson, 1881

Pallenopsis patagonica (Hoek, 1881) is one of the most taxonomically problematic and variable pycnogonid species, and is distributed around the southern South American coast, and the Subantarctic and Antarctic areas. We conducted a phylogenetic analysis of mitochondrial cytochrome c oxidase subunit I (COI) sequences of 47 Pallenopsis specimens, including 39 morphologically identified as P. patagonica, five Pallenopsis pilosa (Hoek, 1881), one Pallenopsis macneilli Clark, 1963, one Pallenopsis buphtalmus Pushkin, 1993, and one Pallenopsis latefrontalis Pushkin, 1993. Furthermore, we studied morphological differences between the different COI lineages using light and scanning electron microscopy, including also material from Loman's and Hedgpeth's classical collections, as well as Hoek's type material of P. patagonica from 1881. The molecular results unambiguously reveal that P. patagonica is a complex of several divergent clades, which also includes P. macneilli, P. buphtalmus, and P. latefrontalis. Based on the material available, two major clades could be identified, namely a ‘Falkland’ clade, to which we assign the nominal P. patagonica, and a ‘Chilean’ clade, which is distinct from the ‘Falkland’ clade. We describe the ‘Chilean’ clade as new species, P allenopsis yepayekae sp. nov. Weis, 2013. All molecular results are confirmed by specific morphological characteristics that are discussed in detail and compared with Pallenopsis species closely related to the P. patagonica complex. Our results reveal that P. patagonica is a species‐rich complex that is in need for a thorough taxonomic revision, using both morphological and genetic approaches. © 2014 The Linnean Society of London     

Habitat Utilization and Depth Distribution of Small Cryptobenthic Fishes (Blenniidae, Gobiesocidae, Gobiidae, Tripterygiidae) in Ibiza (Western Mediterranean Sea)

The paper describes the habitat utilization of small cryptobenthic fishes of the families Blenniidae (Lipophrys nigriceps, and Parablennius zvonimiri), Gobiesocidae (Apletodon incognitus, Gouania wildenowi, Lepadogaster candollei, and L. lepadogaster), Gobiidae (Chromogobius zebratus, Corcyrogobius liechtensteini, Didogobius splechtnai, Gammogobius steinitzi, Millerigobius macrocephalus, Thorogobius ephippiatus, T. macrolepis, and Zebrus zebrus), and Tripterygiidae (Tripterygion melanurus). Nine different habitats from the waterline to a depth of about 40m were examined. The depth distributions of the single species and co-occurrences with other cryptobenthic fish species are given.     

Evolutionary systematics of the Australian Cyzicidae (Crustacea,Branchiopoda, Spinicaudata) with the description of a new genus

In Australia's arid and semi‐arid zone, most aquatic habitats are nonpermanent. Although approximately 70% of its land surface belongs to these zones, very little is known of the iconic ‘large branchiopods’ that inhabit these important and widespread habitats. In the present study, we investigated 737 Australian specimens of the spinicaudatan taxa Caenestheria and Caenestheriella with a combination of one mitochondrial (cytochrome oxidase subunit I; COI) and three nuclear (elongation factor 1α, internal transcribed spacer 2, and 28S) markers to assess the diversity of species, their phylogenetic relationships, and phylogeographical history. The initial species delimitation was based on COI employing a combination of phylogenetic analyses and two automated approaches to species delimitation (general mixed Yule coalescent model and Automated Barcode Gap Discovery). The outcome was tested by the nuclear markers and considered under differing species concepts. The number of delineated species ranged from 14–27, in no case being in full agreement with any of the two automated approaches. The lower numbers resulted if inferred reproductive isolation, as required for the biological or Hennigian species concept, was employed. Although nuclear markers did not indicate ongoing reproduction, the lack of sympatric co‐occurrences inhibited inferences of definitive reproductive isolation in several instances. If monophyly or an ‘independent evolutionary fate’ was employed, as required for the phylogenetic or evolutionary species concepts, the species' distribution was of no importance and up to 27 species could be delimitated. Because the Australian representatives of both studied genera could not be clearly separated from each other but constitute a single monophyletic clade separated from all available non‐Australian representatives of these genera, we describe a new spinicaudatan genus Ozestheria gen. nov. to accommodate these species. Populations revealed relatively small levels of genetic differentiation over large areas of central and eastern Australia. By far the most pronounced levels of genetic differentiation were observed towards the north‐eastern regions, a pattern possibly explainable by ecological conditions and the movement of nomadic water birds that disperse resting eggs. © 2015 The Linnean Society of London     

Species limits in molecular phylogenies: a cautionary tale from Australian land snails (Camaenidae: Amplirhagada Iredale, 1933)

By complementing two independent systematic studies published recently on the Western Australian land snail Amplirhagada, we compare levels of morphological variation in shells and genitalia with those in the mitochondrial markers cytochrome c oxidase (COI) and 16S to evaluate the utility of mtDNA markers for delimiting species. We found that penial morphology and mitochondrial divergence are generally highly consistent in delimiting species, while shells have little overall taxonomic utility in these snails. In addition to this qualitative correspondence, there is almost no overlap between intraspecific and interspecific genetic distances in COI, with the highest intraspecific and lowest interspecific distance being 6%. This value is twice the general level suggested as a DNA barcode threshold by some authors and higher than the best average found in stylommatophoran land snails. Although in Amplirhagada land snails DNA barcoding may provide meaningful information as a first‐pass approach towards species delimitation, we argue that this is due only to specific evolutionary circumstances that facilitated a long‐termed separate evolution of mitochondrial lineages along spatial patterns. However, because in general the amounts of morphological and mitochondrial differentiation of species depend on their evolutionary history and age, the mode of speciation, distributional patterns and ecological adaptations, and absence or presence of mechanisms that prevent gene flow across species limits, the applicability of DNA barcoding has to be confirmed by morphological studies for each single group anew. Based on evidence from both molecular and morphological markers, we describe six new species from the Bonaparte Archipelago and revise the taxonomy of a further two. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 337–362.     

An altitudinal comparison of caterpillar (Lepidoptera) assemblages on Ficus trees in Papua New Guinea

Aim This analysis of caterpillar (Lepidoptera) beta‐diversity between tropical lowlands and highlands attempts to separate the effects of between‐site (1) turnover of herbivore species on particular host plants, (2) changes in host use by herbivores, and (3) turnover of plant species on changes in herbivore assemblages. Location Two rain forest areas 130 km and 1700 altitudinal metres apart were studied in Papua New Guinea: one in the lowlands (100 m a.s.l.) on the northern coast of the island and one in the central New Guinean cordillera at 1800 m a.s.l. Methods The analysis is based on caterpillar feeding records obtained by quantitative sampling and rearing of caterpillars from four Ficus species studied in the mountains and 21 Ficus species and 62 plant species from other genera and families studied in the lowlands, including three Ficus species studied in both areas. Results Only 17% of species feeding on Ficus in the highlands also occurred in the lowlands. These species represented 1–46% of individuals in caterpillar assemblages on particular Ficus hosts. Widespread species included both Ficus specialists and generalists feeding on numerous plant families. Some of the Ficus specialists changed their preferred host species with altitude. High species turnover was not explained by changes in the species composition of host plants with altitude as lowland and montane assemblages feeding on the same Ficus species showed high turnover. Despite the rarity of widespread caterpillars, the lowland and montane Ficus assemblages were remarkably similar in their dominance structure, species richness, host specificity, generic composition and familial composition. Main conclusions Ficus‐feeding Lepidoptera assemblages between tropical lowlands and highlands are characterized by substantial species turnover not explained by altitudinal changes in the composition of the vegetation. Further, species‐rich plant genera can support caterpillar assemblages with relatively low beta‐diversity compared with species‐poor genera as caterpillars can switch their host preferences from one congeneric host species to another along an altitudinal gradient. Closely related plant species can thus represent a broad, continuously distributed resource along such gradients.     

Maximizing information in systematic revisions: a combined molecular and morphological analysis of a cryptic green pitviper complex (Trimeresurus stejnegeri)

Although the integration of DNA information in taxonomy has been invaluable, logistical problems relating to sampling can seriously limit its applicability. Here we describe the analysis of a morphologically cryptic species complex, in which we maximize the information present by using both a DNA phylogeny and a multivariate morphometric approach. The green pitviper Trimeresurus stejnegeri s.l. is widespread in Asia, with a number of described subspecies (some of which are considered full species by some workers) and two new species that have recently been described from Thailand. The phylogeny indicates three clades, which can also be discerned in the principal component analyses of morphological variation. Combining molecular and morphological information permits evaluation of the taxonomic position of populations not represented in the phylogeny − in particular, the subspecies T. s. chenbihui and T. s. yunnanensis . We discuss nomenclatural issues raised by this analysis, although these cannot be fully resolved until the holotypes of these subspecies can be examined. Finally, we apply a molecular clock calibrated in New World pitvipers, and discuss some of the palaeoclimatic changes that might have impacted upon diversification in this group.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 82 , 219–235.     

Phylogeography of the East Asian polymitarcyid mayfly genus Ephoron (Ephemeroptera: Polymitarcyidae): a comparative analysis of molecular and ecological characteristics

In East Asia, the mayfly genus Ephoron, a member of Polymitarcyidae, has been classified into three species: Ephoron eophilum, Ephoron limnobium, and Ephoron shigae. Using the nuclear histone 3 and internal transcribed spacer 1 and mitochondrial 16S rRNA and cytochrome c oxidase subunit I genes, we investigated the phylogenetic relationships of these mayflies. Ephoron limnobium formed polyphyletic relationships within the clade of Japanese E. shigae and shared identical sequences with E. shigae, suggesting that E. limnobium is a synonym of E. shigae. Monophyly was supported in E. eophilum, Korean E. shigae, and E. limnobium + Japanese E. shigae. Ephoron eophilum that co‐occurs with the other Ephoron species has several peculiar traits in its adult swarming period and karyotype. This suggests that both pre‐ and post‐zygotic isolation are likely to have promoted speciation of these Ephoron species. The divergence between E. eophilum and E. shigae would have occurred from the late Late Miocene to Early Pliocene according to the Bayesian relaxed clock model calibrated using the mitochondrial substitution rate. The area currently inhabited by E. eophilum emerged above sea level some 0.1 Mya, suggesting that E. eophilum moved into this area from other areas that it occupied prior to this time. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 181–202.     

High molecular and phenotypic diversity in the Merodon avidus complex (Diptera,Syrphidae): cryptic speciation in a diverse insect taxon

This paper examines molecular and phenotypic variability in the widely spread European hoverfly species complex Merodon avidus. Herein, based on the mitochondrial DNA (mtDNA) sequences of the cytochrome c oxidase subunit I (COI) and morphometric wing parameters, M. avidus is shown to comprise a complex of cryptic species, and one variety is redefined as a valid species: M. bicolor Gil Collado, 1930 (as var. of spinipes). The species M. bicolor, M. avidus A, and M. avidus B were clearly delimited based on their wing size. A total of 29 M. avidus and M. bicolor individuals presented 20 mtDNA haplotypes, four of which were shared by M. avidus A and M. avidus B, three were confined to M. bicolor, seven to M. avidus A, and six to M. avidus B. Sequence divergences between lineages occurring in the Balkan and in Spain ranged from 4.93 to 6.0 (uncorrected p in %) whereas divergences between M. avidus A and M. avidus B were 0.26 to 1.56. Divergence among morphologically identified individuals of M. avidus A and M. avidus B species ranged from 0.13 to 1.58, and from 0.13 to 0.52, respectively. The phenotypic substructuring and observed genetic uniqueness of populations in spatially and temporally fragmented M. avidus taxa were used to identify genetic units. The early split of two allopatric lineages, Spanish M. bicolor and Balkan M. avidus, was followed by diversification in each lineage. Present‐day morphological uniformity masks much of the genetic complexity of lineages within the M. avidus complex. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 819–833.     

Genital morphology and taxonomy of the water strider Aquarius remigis (Say) (Insecta, Hemiptera-Heteroptera: Gerridae)

The shape of the dorsal vesical plate was used to determine the extent of morphological differentiation among populations of the water strider Aquarius remigis (Say) (Hemiptera-Heteroptera: Gerridae), and between species assigned to the A. remigis species group. Populations were sampled throughout North America and Mesoamerica, and included paratypes of A. remigoides Gallant & Fairbairn, and material collected from the type localities of A. amplus (Drake & Harris) and A. nyctalis (Drake & Hottes). If taxonomy is to be inferred from the shape of the dorsal vesical plate, as suggested by previous authors, several taxonomic issues need to be reconsidered. First, there was one species distributed widely across North America and deep into Mexico that is very likely to represent A. remigis , meaning that populations from the western USA previously assigned to ' A. nyctalis ' should be synonymized with this species. Second, A. remigoides as currently defined also includes some populations of A. remigis , and is probably much less widely distributed in the south-eastern USA than previously thought. A hybridization zone in Pennsylvania between A. remigis and A. remigoides , as inferred from measurements of body size and allozyme electrophoresis, is not congruent with data from the male genitalia, which indicated a transition zone between the two forms in Virginia much further to the south. Finally, A. amplus was widespread in Mexico, reaching into Guatemala to the south and into Arizona to the north.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 381–398.     

Morphology,bioacoustics, and ecology of Tibicen neomexicensis sp. n., a new species of cicada from the Sacramento Mountains in New Mexico,U.S.A. (Hemiptera,Cicadidae, Tibicen)

Tibicen neomexicensissp. n., a new species of cicada found in the Sacramento Mountains of southcentral New Mexico, is described. Tibicen neomexicensis closely resembles Tibicen chiricahua Davis morphologically, but males of the two species have highly distinct calling songs that differ in phrasal structure, amplitude burst rates, and pulse structure. Unlike Tibicen chiricahua, male Tibicen neomexicensis use conspicuous dorso-ventral abdominal movements to modulate the amplitude and frequency of their calls. Tibicen neomexicensis is also smaller on average than Tibicen chiricahua, and differences in the color patterns of the wing venation identify these two species morphologically. Both species are dependent on pinyon-juniper woodlands and have similar emergence phenologies. These species appear to be allopatric, with Tibicen chiricahua found west of the Rio Grande in New Mexico, Arizona, and Mexico, and Tibicen neomexicensis so far known only from New Mexico, east of the Rio Grande. Tibicen chiricahua and Tibicen neomexicensis males share a common genitalic structure that separates them from all other species of Tibicen, and the possible evolutionary and biogeographic history of these likely sister species is also discussed.     

Morphological and molecular differentiation of invasive freshwater species of the genus Corbicula (Bivalvia, corbiculidea) suggest the presence of three taxa in French rivers

Asiatic Clams are common in brackish and fresh water in Asia, and they were introduced into North America in 1924 and have now spread throughout the continent. During the last two decades they have been reported in Europe, but the number of species here is uncertain. Populations of Corbicula from France and the Netherlands were analysed morphologically and genetically to quantify the degree of species and/or population differentiation. The morphological and genetic data, based on allozymes and mitochondrial sequences, were in full agreement. They indicate that there are two distinct species, identified as C. fluminalis and C. fluminea, in the two countries. Analyses of the mitochondrial COI gene revealed an unexpected divergent population of Corbicula in the Rhône. All these individuals were morphologically identified as C. fluminea, but had a COI sequence different from the two previous species. This population may, therefore, be a more ancient population, or a distinct species introduced via a different colonization route.