The male postabdomen and reproductive system ofBibio marciLinnaeus, 1758 (Hexapoda: Diptera: Bibionidae)

Abstract

The male postabdomen and the internal parts of the male genital system of Bibio marci (Bibionomorpha) were examined and reconstructed 3‐dimensionally. Several features differ from the presumptive dipteran groundplan. The bases of the gonopods are fused with each other and with tergite IX. The penis is not tube‐shaped and only sclerotized on the ventral side. The vasa deferentia are S‐shaped, and two pairs of accessory glands are present. In contrast to these characteristics, the arrangement of the internal parts is probably close to the ancestral condition. With its specific shape, the penis is well suited for the transfer of a spermatophore. The dorsal sclerite of the copulatory organ probably represents the medially fused parameres. A cladistic analysis of 27 characters of the postabdomen yielded two most parsimonious trees, with the strict consensus as follows: Nannochoristidae (outgroup) + (Culicidae [Culicomorpha] + ((Nymphomyiidae + (Tipulidae + Trichoceridae)) + (Tabanidae [Brachycera] + (Bibionidae, Anisopodidae, Axymyiidae [Bibionomorpha])))). Potential synapomorphies of Bibionomorpha (including Axymyiidae) and Brachycera are the fusion of sternum IX with the gonocoxites, the fusion of the parameres forming the dorsal sclerite and the presence of an entire series of postabdominal muscles (M4, M20, M23, M26, M27, M31, M35 and M37). The results of the analysis are preliminary as it is based on a single‐character system with a limited taxon sampling. However, the main result – a clade Bibionomorpha + Brachycera – is fully compatible with current hypotheses on dipteran phylogeny.

Entomological Collections in the Age of Big Data

“…Although some permit destructive methods for sampling DNA, such methods preclude preservation of a meaningful voucher and the single-use nature of such potentially irreplaceable specimens is not desirable. Fortunately, several nondestructive or minimally destructive methods for extracting genetic material have been developed for insect specimens (18,45,124,134,136). These methods do not generally require damage or trauma to the exterior of the specimen, although soft tissues may be lost in the process.…”

“…In fact, for most DNA barcoding studies in insects, only a single mitochondrial gene fragment, cytochrome oxidase I, is included (48,122), an approach that has come under criticism in the scientific literature (59,82,94,123). Although there are concerns about the broad utility of DNA barcoding, this method has been successfully used on DNA obtained from insect and other arthropod museum specimens (51,88,124). The small number of developed primer sets can be viewed as a limitation, but the limited number has also permitted the combination of independently developed data sets to produce a broader understanding of the phylogenetic relationships of groups of arthropod taxa or to facilitate integrative taxonomy; examples include beetles (58), centipedes (46), ants (12,92), and butterflies (142).…”

“…Probably the biggest boost to morphology outside of improved microscopes was the advent of digital, threedimensional (3D) reconstructions of morphological features (25,44). Such 3D data have been used for deciphering the phylogenetic relationships of insect taxa (e.g., 9,41,42,43,55,102), obtaining additional data from amber and compression fossils (e.g., 1,50,101,104,117,132), examining internal anatomy (e.g., 35,40,68,86,87,105,124,152), investigating internal musculature used for power-amplified movements (e.g., 149), and describing new species in taxonomic revisions (e.g., 37,84,85,127). However, Deans et al (25, p. 328) highlight that "internal anatomy remains a largely untapped resource for evidence of taxonomic association and evolutionary history" and call for expanded use of modern techniques that provide access to internal features.…”

Skeleton and musculature of the male abdomen in Tanyderidae (Diptera, Nematocera) of the Southern Hemisphere

“…Therefore, as the first step for further comparison, a table with the presumed homology of musculature among families was compiled (Table 1). Recently a similar attempt of homologization was undertaken for other families of Diptera (Spangenberg et al 2012).…”

Rediscovered at last: a new enigmatic genus of Axymyiidae (Diptera) from western North America

“…(Borkent & Sinclair 2012;Sinclair et al 2013). In an analysis of the male postabdomen, Spangenberg et al (2012) placed Bibionidae, Anispodidae and Axymyiidae together in a clade, assigned as sister group to the Brachycera. Among synapomorphies supporting the entire clade was fusion of the hypandrium with the gonocoxites and parameres fused into a dorsal sclerite.…”