Systematics and Biogeography of the New World Genus Plumolepilius (Coleoptera: Curculionidae)

Plumolepilius Barrios-Izás & Anderson, 2016 is a leaf litter weevil genus that inhabits montane broadleaf forests from southern Mexico to northern Panama. The genus consists of 27 species, 22 distributed in the Chiapas Highlands province (Mexican Transition Zone) and 5 found in the Pacific dominion (Neotropical region) in Costa Rica and Panamá. Here, we analyze the phylogenetic relationships of the species of Plumolepilius based on 20 external body characters and 9 characters from the genitalia. The first dichotomy of the cladogram separates two species from the Pacific dominion from the remaining species of Plumolepilius from the Chiapas Highlands province and three species restricted to the Pacific dominion. We hypothesize that redundant distributions in the taxon-area cladogram of the genus may be due to dispersal events, probably during the Pleistocene glaciations.

Three new species of Botanophila Lioy (Diptera: Anthomyiidae) from the Mexican Transition Zone

The genus Botanophila Lioy has several species distributed in North America, but none had been recorded from Mexico. Here we describe three new species of Botanophila from the highlands of the Mexican Transition Zone. We include images of habitus, drawings of the terminalia and a key to facilitate the identification of species. Remarkably, the male of the new species has dichoptic eyes, an unusual characteristic in Anthomyiidae.

Population differentiation and phylogeography in Lycianthes moziniana (Solanaceae: Capsiceae), a perennial herb endemic to the Mexican Transition Zone

Lycianthes moziniana (Solanaceae: Capsiceae) is a perennial herb with edible fruits that is endemic to Mexico. Three varieties are recognized, all known in the Mexican Transition Zone. Lycianthes moziniana var. margaretiana grows in the Sierra Madre Oriental, whereas L. moziniana var. moziniana is common along the Trans-Mexican Volcanic Belt and in the Sierra Madre Occidental. Lycianthes moziniana var. oaxacana is found exclusively in the Sierra Madre del Sur. The Mexican Transition Zone is a complex geological, climatic and biogeographical area, the result of tectonic and volcanic activity that has promoted genetic divergence and speciation. We determined the genetic variation and structure of L. moziniana. Using phylogeographical approaches, we described the demographic history and evolutionary processes leading its divergence. The intergenic spacers rpl32-trnL and ycf1 were sequenced for 133 individuals pertaining to 15 populations. The genealogical relationships were analysed using haplotype networks. Finally, based on ecological niche models, we inferred the palaeodistribution of L. moziniana during the Pleistocene. The genetic differences and the haplogroups matched the three described varieties. Geological and climatic events of the Mexican Transition Zone facilitated these results. The Trans-Mexican Volcanic Belt isolated the populations of the Sierra Madre Oriental and the Sierra Madre del Sur, while allowing the migration to the Sierra Madre Occidental, during the middle Holocene.

New genus of Muscidae: Coenosiinae (Diptera) from the Mexican Transition Zone and its phylogenetic position based on morphological evidence

A new monotypic genus, Aztecamyia gen. nov., is proposed for a new species of muscid fly, Aztecamyia tlaloc sp. nov., found in highland localities from the Mexican Transition Zone (Mexico, Michoacan, Morelos and Puebla). Additionally, a morphology-based phylogenetic analysis of Coenosiini is presented. The new genus has some unique characters, such as katepisternal setae 0+1+1 in males, while females are the typically Coenosiini 1+1+1; the mid and hind tibia have many long and fine setae on the apical half, from the anterior to posterior surface; and the preapical setae on all femora are absent on all surfaces. The morphology of the male and female terminalia is a typical Coenosiini shape.