Astrotischeria andina Stonis & Diškus & Remeikis & Orlovskytė & Katinas 2024

Molecular considerations of Astrotischeria andina sp. nov. occurring at the record-high elevations The 650 bp fragment of mtDNA CO1 is highly functional in species identification for various animal groups (Hebert et al. 2003a). However, it is difficult to obtain this sequence from air-dried museum specimens because of DNA degradation. For such cases, a universal DNA mini-barcode can be used (Hajibabaei et al. 2006; Meusnier et al. 2008). In this study, we successfully sequenced the 133 bp long DNA mini-barcode of Astrotischeria andina Diškus & Stonis, sp. nov., a species occurring at record-high elevations. This sequence was included in our molecular analyses using the NJ method with an Opostegidae outgroup. Unfortunately, none of them yielded a fully resolved tree: the best outcomes still had doubtful dichotomies and low bootstrap support values. The challenge of obtaining fully resolved molecular trees of Astrotischeria was briefly discussed in the monograph “Genera of Tischeriidae: a review of the global fauna” (Stonis et al. 2023). In this publication, it was hypothesized that the partial sequences of the mtDNA CO1 are not useful for discrimination of Astrotischeria species, what is common in cases where the rate of evolution is extremely high. Nevertheless, our study showed that each species involved in the analyses is distinct, including A. andina sp. nov. According to Hebert et al. (2003b), 2% of evolutionary divergence of the mtDNA CO1 sequences is a threshold for 98% of animal species, while the distinction of analysed Astrotischeria species ranged from 5.26 ± 2.3% (between A. andina sp. nov. and A. atlantica Diškus & Stonis) to 17.69± 4.07% (between A. jociui Diskus & Stonis and A. colombiana Stonis & Vargas). In half of our molecular trees, A. andina sp. nov., as a separate clade, clustered with A. yungasi Diškus & Stonis; however, this was never reliable, with very low bootstrap support values. In the other half of our analyses, A. andina sp. nov., as a separate clade, clustered with A. atlantica (Fig. 60), and sometimes with sufficient bootstrap support values. While the cluster A. andina sp. nov. + A. yungasi is not supported by morphological data or biology (host plants are from Asteraceae but very different), the cluster A. andina sp. nov. + A. atlantica can be substantiated by certain similarities in the male genitalia. Moreover, both species feed on the same plant genus, Baccharis L.: A. andina sp. nov. on B. buxifolia, and A. atlantica on B. spicata. Neither of our molecular trees have proven that species from high altitudes are closely related (i.e., represent a certain phylogenetic trend of high-elevation species). Moreover, A. andina sp. nov. and A. atlantica, two species forming one phylogenetic cluster, represent two opposite extremes: the first occurring at record-high altitudes in the Peruvian Andes, while the latter is known from an altitude around 5 m on the Atlantic coast of Argentina.