Comparative phylogeography uncovers evolutionary past of Holarctic dragonflies.

Here, we investigate the evolutionary history of five northern dragonfly species to evaluate what role the last glaciation period may have played in their current distributions. We look at the population structure and estimate divergence times for populations of the following species: Aeshna juncea (Linnaeus), Aeshna subarctica Walker, Sympetrum danae (Sulzer), Libellula quadrimaculata Linnaeus and Somatochlora sahlbergi Trybom across their Holarctic range. Our results suggest a common phylogeographic pattern across all species except for S. sahlbergi. First, we find that North American and European populations are genetically distinct and have perhaps been separated for more than 400,000 years. Second, our data suggests that, based on genetics, populations from the Greater Beringian region (Beringia, Japan and China) have haplotypes that cluster with North America or Europe depending on the species rather than having a shared geographic affinity. This is perhaps a result of fluctuating sea levels and ice sheet coverage during the Quaternary period that influenced dispersal routes and refugia. Indeed, glacial Beringia may have been as much a transit zone as a refugia for dragonflies. Somatochlora sahlbergi shows no genetic variation across its range and therefore does not share the geographic patterns found in the other circumboreal dragonflies studied here. Lastly, we discuss the taxonomic status of Sympetrum danae, which our results indicate is a species complex comprising two species, one found in Eurasia through Beringia, and the other in North America east and south of Beringia. Through this study we present a shared history among different species from different families of dragonflies, which are influenced by the climatic fluctuations of the past.

Identifying possible sister groups of Cryptocercidae+Isoptera: a combined molecular and morphological phylogeny of Dictyoptera.

Termites (Isoptera) offer an alternative model for the development of eusociality which is not dependent on a high degree of relatedness as found between sisters in hymenopterans (bees, wasps, ants). Recent phylogenetic studies have established that termites belong within the cockroaches as sister to the subsocial Cryptocercidae. Cryptocercidae shares several important traits with termites, thus we need to understand the phylogenetic position of Cryptocercidae+Isoptera to determine how these traits evolved. However, placement of Cryptocercidae+Isoptera is still uncertain. We used both molecular (12S, 16S, COII, 18S, 28S, H3) and morphological characters to reconstruct the phylogeny of Dictyoptera. We included all previously suggested sister groups of Cryptocercidae+Isoptera as well as taxa which might represent additional major cockroach lineages. We used Bayes factors to test different sister groups for Cryptocercidae+Isoptera and assessed character support for the consensus tree based on morphological characters and COII amino acid data. We used the molecular data and fossil calibration to estimate divergence times. We found the most likely sister groups of Cryptocercidae+Isoptera to be Tryonicidae, Anaplecta or Tryonicidae+Anaplecta. Anaplecta has never previously been suggested as sister group or even close to Cryptocercidae+Isoptera, but was formerly placed in Blaberoidea as sister to the remaining taxa. Topological tests firmly supported our new placement of Anaplecta. We discuss the morphological characters (e.g. retractable genitalic hook) that have contributed to the previous placement of Anaplecta in Blaberoidea as well as the factors that might have contributed to a parallel development of genitalic features in Anaplecta and Blaberoidea. Cryptocercidae+Isoptera is placed in a clade with Tryonicidae, Anaplecta and possibly Lamproblattidae. Based on this, we suggest that wood-feeding, and the resultant need to conserve nitrogen, may have been an important factor in the development of termite eusociality. Nocticolidae was placed as sister group to Latindia+Paralatindia (both Corydiidae), this clade was in turn placed as sister group to the remaining Corydiidae. The Nocticolidae+Corydiidae clade is supported by both morphological and COII amino acid changes. Our divergence time estimates placed the split between Mantodea and Blattodea at 273mya (middle Permian) and the splits between the major blattodean lineages no later than 200mya (end of Triassic).

Derived morphology in a basal moth: The uniquely specialized sternum V glands of Agathiphaga (Lepidoptera: Agathiphagidae).

The sternum V gland is a notable specialization shared by basal Lepidoptera and most Trichoptera; it is generally present in both sexes or in females only. In both orders the secretory cells usually discharge into a sac-like reservoir from which a duct leads to the opening on sternum V. In contrast, the gland in agathiphagid moths is only present in males and it exhibits several unique specialisations: the glandular portion being the apical (morphologically anterior) part of a long tubular cuticular invagination covered with contiguous 'type-3' glandular units; together with the following part of the efferent duct it is coiled like a ball of yarn; the duct expands into a fusiform reservoir, and a separate small sac surrounded by a complex muscular coat is present just inside the gland opening. The principal opener muscle of each gland originates on the contralateral side of sternum VI, hence crossing its counterpart in the midline. Characters of the agathiphagid sternum V gland, the function of which remains unclear (though sex pheromone production may appear most likely), add significantly to the suite of autapomorphies exhibited by this otherwise overall remarkably generalized moth taxon.

Phylogenetics and divergence times of Papilioninae (Lepidoptera) with special reference to the enigmatic genera Teinopalpus and Meandrusa.

© The Willi Hennig Society 2010. ABSTRACT: Phylogenetic relationships of 18 genera of the swallowtail subfamily Papilioninae, four genera of Parnassiinae, and the monobasic Baroniinae are inferred based on 94 morphological characters and 5616 bp DNA from seven genes (16S, COI, COII, ND1, ND5, EF-1 alpha and wingless). Bayesian likelihood analyses show that Baroniinae are the sister of a clade comprising Parnassiinae and Papilioninae. Four Papilioninae tribes are recognized, Leptocircini, Teinopalpini, Papilionini and Troidini, with Leptocircini being the sister of the remaining tribes. Meandrusa and Teinopalpus are sister taxa and comprise the tribe Teinopalpini, which is the sister of a clade comprising Papilionini and Troidini. The tribe Troidini (pipevine swallowtails) comprises two subtribes: Battina (including only Battus) and Troidina. The endemic Madagascan genus Pharmacophagus is consistently placed as the sister to the remaining Troidina. The non-Pharmacophagus Troidina are tentatively divided into a Neotropical lineage and an Australasian lineage. Dispersal-vicariance analyses indicate that past dispersal events are most important for explaining current distribution patterns of Papilionidae. However, the division of the non-Pharmacophagus Troidina into a Neotropical lineage and an Australasian lineage is possibly due to the final break-up of southern Gondwana. A fossil-calibrated relaxed Bayesian molecular clock analysis confirms that the ages of the lineages fit this scenario. The basal lineages leading to the current subfamily-level diversity of Papilionidae probably arose around the K/T boundary. Analyses of larval host-plant relationships within Papilionidae show very little phylogenetic pattern. However, Aristolochiaceae-feeding apparently evolved independently in non-Parnassiini parnassiines and Troidini.