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Abstract: Extreme large body size is rare in modern Zygoptera (damselflies). Only the South and Central American damselfly family Pseudostigmatidae and one African species, Coryphagrion grandis, share the morphological trait of gigantism. By means of phylogenetic analyses using two mitochondrial markers (16S rDNA and ND1) and one nuclear marker (EF1) in combination with an existing morphological data set, we trace the evolution of gigantism in damselflies. Individual and combined data sets were analyzed using the maximum parsimony, minimum evolution and maximum likelihood algorithms. Regardless of the algorithm used and the data set analyzed all principal tree topologies support a monophyly of the damselfly taxa displaying giant body size. This supports the view that the evolution of gigantism in damselflies from Africa and South America is not the result of convergent evolution due to strikingly similar habitat preferences, but rather the result of close genealogical relationship. Because modern odonates evolved before the split of Africa from Gondwanaland, the proposed phylogeny suggests that C. grandis represents a Gondwana relict. [Copyright &y& Elsevier]

Abstract: The Maracaibo basin in northwestern Venezuela is home to over 108 species of freshwater fishes, over half of which occur nowhere else. The rise of the Mérida Andes between 8 and 10 million years ago is believed to have divided a preexisting biota and facilitated allopatric speciation. The distinctive “phractocephaline” clade of pimelodid catfishes has a distribution that includes the Maracaibo historically and today is represented by Perrunichthys (Maracaibo endemic), Leiarius, Phractocephalus, and Steindachneridion. A resolved and well-supported phylogeny was obtained from the phylogenetic analysis of over 3.4kb (including cytochrome b, NADH dehydrogenase subunit 1, recombination activating gene subunit 2). Rates of divergence among “phractocephalines” were calibrated with fossil material and the Mérida uplift. These independent calibrators provided different node-age estimates when the rates were applied separately to the gene partitions (mtDNA and rag2). Node-age discrepancies were particularly evident at older nodes. This is due to two factors: (1) multiple substitution of mtDNA underestimates the amount of change and therefore time since cladogenesis, whereas (2) calibration of an ancient node with fossils produces an artificially slow rate (due to the masking of divergence through multiple substitution) that overestimates time when applied to younger nodes. Node-age estimates provided by the more slowly evolving rag2 sequences were more consistent with other sources of historical inference, e.g., paleogeography and the fossil record. Given these points, we provide a synthetic chronology of diversification and discuss the reasons for its preference. The phylogeny and synthetic chronology suggest Perrunichthys perruno (Maracaibo endemic) and Leiarius pictus (Orinoco and Guianas) to be a vicariant species pair that last shared a common ancestor during the period of Mérida uplift. [Copyright &y& Elsevier]

Abstract: Zygaenid moths are capable of releasing hydrogen cyanide in their defense by enzymatic break-down of cyanoglucosides, but only larvae of chalcosiine and zygaenine moths store cyanogenic compounds in cuticular cavities and thus are able to discharge defense droplets, which effectively deter potential predators. A previously proposed phylogeny of Zygaenidae hypothesized a sister group relationship of chalcosiine and zygaenine moths because of their similar larval defense system. Not all chalcosiine taxa possess cuticular cavities, however, and a comparable defense mechanism has been reported in larvae of the zygaenoid family Heterogynidae. Considering sequence data of seven molecular loci, the present study estimates the posterior probability of phylogenetic hypotheses explaining the occurrence of larval cuticular cavities. The molecular data confirm the previous exclusion of Himantopteridae from Zygaenidae and suggest their close affinity to Somabrachyidae. The sequence data also corroborate the recently proposed exclusion of the Phaudinae from the Zygaenidae, because this subfamily is recovered in a reasonably well supported species cluster consisting of members of the families Lacturidae, Limacodidae, Himantopteridae, and Somabrachyidae. We consequently agree to raise Phaudinae to family rank. Within Zygaenidae, the subfamilies Callizygaeninae, Chalcosiinae, and Procridinae most likely constitute a monophyletic group, which is sister to the Zygaeninae. Our results imply that cuticular cavities were probably present in the larvae of the most recent common ancestor of Zygaenidae. Heterogynidae cannot be confirmed as sister taxon to this family, but appear at the very first split of the Zygaenoidea, although with poor support. The specific pattern of taxa in the molecular phylogeny showing larval cuticular cavities opens the possibility that these structures could have been already present in the most recent common ancestor of the Zygaenoidea. [Copyright &y& Elsevier]

The Holoarctic termite genus Reticulitermes is widely distributed in Europe. A new Reticulitermes species, R. sp. nov, was recently found in France and Italy. Its phylogenetic position was investigated using a 743-bp fragment of mitochondrial 16S rRNA-ND1 genes and 382-bp of the nuclear ITS2 region. Phylogenies for these sequences were estimated by neighbor-joining, maximum-parsimony and maximum-likelihood analysis. The results strongly supported a relationship between R. sp. nov. and the termite species from the eastern Mediterranean area including Reticulitermes balkanensis from the Balkans, Reticulitermes lucifugus from Turkey and Reticulitermes clypeatus from Israel. The hypothesis of a relationship between R. sp. nov. and the Japanese Reticulitermes speratus was rejected by parametric bootstrap. The current distribution of R. sp. nov. could be linked to postglacial colonization routes between Balkan refuge and northern regions. [Copyright &y& Elsevier]

The genus Myotis includes the largest number of species in the family Vespertilionidae (Chiroptera), and its members are distributed throughout most of the world. To re-evaluate the phylogenetic position of East Asian Myotis species with respect to Myotis species worldwide, we analyzed mitochondrial gene sequences of NADH dehydrogenase subunit 1 and cytochrome b from 24 East Asian individuals as well as 42 vespertilionid bats determined previously. The results suggest that: (1) some individuals having the same species name in Europe and Japan do not form a monophyletic clade, indicating that some bat species exhibit morphological convergence, (2) Japanese Myotis mystacinus forms a sister relationship with Myotis brandtii (Palaearctic), and both species are included in the American clade implying that an ancestor of these species originated in North America, and (3) the Black whiskered bat, Myotis pruinosus, is endemic to Japan and forms sister relationships with Myotis yanbarensis and Myotis montivagus collected from Okinawa (Japan) and Selangor (Malaysia), respectively, implying that M. pruinosus originated from the south. The systematics of Japanese and East Asian Myotis bats were revisited by considering their phylogenetic relationships. Our study provides the first extensive phylogenetic hypothesis of the genus Myotis that includes East Asian and Japanese species. [Copyright &y& Elsevier]

A molecular phylogeny of the bivalve genus Quadrula (Unionidae) was constructed based on nucleotide sequences of the mitochondrial ND1 gene. Phylogenetic analysis of 66 specimens representing 17 of the 20 currently recognized taxa within Quadrula, three closely allied species, and 16 outgroup taxa reveals a non-monophyletic Quadrula due to the placement of Tritogonia verrucosa, ‘Fusconaia’ succissa, and ‘Quincuncina’ infucata. We suggest that the taxonomic description of the genus Quadrula be expanded to include these species. Within the genus, we continue to recognize three monophyletic species groups (the quadrula, metanvera, and pustulosa species groups), as historically described; however, the pustulosa species group must include ‘F.’ succissa and ‘Quincuncina’ infucata. Finally, while our findings place the monotypic genus Tritogonia within Quadrula, its relationship to members within the genus Quadrula remains unresolved. [Copyright &y& Elsevier]