Off-target capture data, endosymbiont genes and morphology reveal a relict lineage that is sister to all other singing cicadas

Abstract

Phylogenetic asymmetry is common throughout the tree of life and results from contrasting patterns of speciation and extinction in the paired descendant lineages of ancestral nodes. On the depauperate side of a node, we find extant ‘relict’ taxa that sit atop long, unbranched lineages. Here, we show that a tiny, pale green, inconspicuous and poorly known cicada in the genus Derotettix, endemic to degraded salt-plain habitats in arid regions of central Argentina, is a relict lineage that is sister to all other modern cicadas. Nuclear and mitochondrial phylogenies of cicadas inferred from probe-based genomic hybrid capture data of both target and non-target loci and a morphological cladogram support this hypothesis. We strengthen this conclusion with genomic data from one of the cicada nutritional bacterial endosymbionts, Sulcia, an ancient and obligate endosymbiont of the larger plant-sucking bugs (Auchenorrhyncha) and an important source of maternally inherited phylogenetic data. We establish Derotettiginae subfam. nov. as a new, monogeneric, fifth cicada subfamily, and compile existing and new data on the distribution, ecology and diet of Derotettix. Our consideration of the palaeoenvironmental literature and host-plant phylogenetics allows us to predict what might have led to the relict status of Derotettix over 100 Myr of habitat change in South America.

Ultraconserved elements reconstruct the evolution of Chagas disease‐vectoring kissing bugs (Reduviidae: Triatominae)

“…Raw reads from each UCE capture dataset were searched using the program MITObim v.1.9.1 (Hahn et al ., 2013) to map reads to 16S mitochondrial rRNA, 18S and 28S nuclear rRNA bait sequences from a representative species of Triatominae as in Simon et al . (2019). The resulting contigs were aligned using the MAFFT v.7 E‐INS‐i algorithm (Katoh et al ., 2018) and manual trimming of apparent misassembled or duplicated segments was conducted before realignment.…”

Cicada timetree by BEAST v1.X verified the recently and exponentially increasing base substitution rates

“…Feeding plants of D. mendosensis are, however, C4 dicots of Amaranthaceae (see figure 9 in Sage 2004) and Chenopodiaceae in degraded salt-plain habitats in arid regions of central Argentina (Simon et al 2019).…”

“…A phylogenetic tree of worldwide cicada was recently constructed by Marshall et al (2018) and Simon et al (2019), applying five concatenated sequences of mitochondrial COI and COII, and nuclear ARD1, EF-1a, and 18S rRNA, and by Łukasik et al (2019), applying whole mitochondrial sequences for representative species.…”

“…1). In the present analyses, we include Derotettix, a relict species of new subfamily of Derotettiginae with the oldest lineage in Cicadidae (Simon et al 2019), and also try to estimate the crown date.…”

Alternative transmission patterns in independently acquired nutritional co-symbionts of Dictyopharidae planthoppers

“…However, in many host clades, one or both became complemented or replaced by other microbes. For example, an Alphaproteobacterium Candidatus Hodgkinia cicadicola (further referred to as Hodgkinia) has replaced the beta-symbiont in the ancestor of modern cicadas (family Cicadidae), but has itself became repeatedly replaced by fungi from the genus Ophiocordyceps (13,14).…”