Total evidence phylogenetic analysis and reclassification of Euschistus Dallas within Carpocorini (Hemiptera: Pentatomidae: Pentatominae)

Abstract

Robust phylogenetic hypotheses have become key for studies addressing the evolutionary biology and ecology of various groups of organisms. In the species-rich heteropteran superfamily Pentatomoidea, phylogenies at lower taxonomic levels are still scarce and mostly employ exclusively morphological data. In this study, we conducted a total evidence phylogeny focusing on the tribe Carpocorini (Pentatomidae), using morphological data and four DNA markers (COI, Cytb, 16S and 28S rDNA; ∼2330 bp; 32 taxa) in order to investigate the relationships within Euschistus Dallas, one of the most speciose pentatomid genera, and between Euschistus and related genera. Our hypotheses generated by maximum likelihood and Bayesian inference show that the current taxonomic composition and classification of Euschistus and allied genera are in need of revision. Euschistus was recovered as nonmonophyletic, with the subgenera forming four independent lineages: Euschistus (Euschistus) and Euschistus (Lycipta) Stål are sister groups; Euschistus (Euschistomorphus) Jensen-Haarup is more closely related to Dichelops Spinola and Agroecus Dallas; and Mitripus Rolston is divided into two clades closely related to Sibaria Stål and Ladeaschistus Rolston. We chose not to change the classification of E. (Euschistomorphus) until further data become available, and propose to split Euschistus into three genera with the exclusion of Euschistus (Mitripus) and all of its species. Here we elevate Mitripus to genus rank to include M. acutus comb.n., M. convergens comb.n. and M. legionarius comb.n., and propose Adustonotus Bianchi gen.n. to include A. anticus comb.n., A. latus comb.n., A. tauricornis comb.n., A. grandis comb.n., A. hansi comb.n., A. paranticus comb.n., A. irroratus comb.n. and A. saramagoi comb.n. We also provide identification keys to the genera Adustonotus gen.n., Ladeaschistus, Mitripus n. rank and Sibaria, here defined as the Mitripus genus group, and to the species of Mitripus and Adustonotus gen.n. Our results provide insights into the current status of the classification of the Pentatomidae, suggesting the need for phylogenetic analyses at different taxonomic levels within stink bugs.This published work has been registered in ZooBank, http://zoobank.org/urn:lsid: zoobank.

Strong functional integration among multiple parts of the complex male and female genitalia of stink bugs

“…Within Euschistus, the biconvex ventral rims of the pygophore in several species are similar to the observed to E. heros, for instance in E. atrox, E. acutus, E. cornutus, E. emoorei, E. irroratus, E. nicaraguensis, E. schaffneri and E. stali (Rolston, 1974;Bunde, Grazia & Mendonça-Junior, 2006). As at least four of these species belong to well-separated lineages (Weiler, Ferrari & Grazia, 2016;Bianchi et al, 2017), we may presume at least four episodes of convergent evolution within this genus. By briefly analyzing the taxonomic literature, we found five other species belonging to other tribes and subfamilies that exhibit similar ventral rims: Acledra spp.…”

Phylogenetic analysis of the Euschistus group (Hemiptera: Pentatomidae) suggests polyphyly of Dichelops Spinola, 1837 with the erection of Diceraeus Dallas, 1851, stat. rev.

“…Bianchi et al . (2017) inferred the monophyly of Euschistus ( Lycipta ) and the nominal subgenus, both as sister groups, and the polyphyly of E . ( Mitripus ) resulting in the erection of Mitripus and Adustonotus .…”

“…The following several genera have been erected from these and could be added to the list: Adustonotus , Ladeaschistus Rolston, 1973; Mcphersonarcys Thomas, 2012, and Mitripus (Rolston 1973; Thomas 2012; Bianchi et al . 2017). Others were more recently related taxonomically to them, i.e.…”

“…2016; Bianchi et al . 2017). The main diagnostic features of this group of genera, informally called the Euschistus group, are the presence of a pair of dorsal processes on the phallotheca (sic dorsal thecal appendages; Rider 1995) and the peritreme spout of the metasternal gland ( sic auriculate ostiolar rugae; Rider et al .…”

“…The polyphyly of Euschistus , the most speciose in the group, has been found recently, resulting in the erection of Mitripus Rolston, 1978 and the description of Adustonotus Bianchi, 2017 (Bianchi et al . 2017). Other findings of Bianchi et al .…”