Synonymizing Peirates turpis and Peirates fulvescens Under Peirates atromaculatus Based on Integrative Taxonomy (Hemiptera: Reduviidae: Peiratinae)

The genus Peirates comprises important predatory assassin bugs that serve as vital biological control agents against agricultural and forestry pests. Thus, accurate species identification is critical for the utilization of these natural enemies. An integrative taxonomic approach was adopted to redefine the species boundaries among P. atromaculatus (Stål, 1870), P. turpis Walker, 1873, and P. fulvescens Lindberg, 1939, which were three related species differentiated by hemelytral color patterns. The COI-based K2P pairwise distances among the three nominal species (range: 0.00–2.61%) were similar to intraspecific variation, with no clear genetic separation between the three morphs. Multi-locus phylogenetic reconstructions derived from mitochondrial and nuclear ribosomal DNA sequencing revealed that individuals from the three color morphs were intermixed within a single evolutionary clade. In addition, geometric morphometric analyses of male genitalia demonstrated extensive overlapping in the shape space. The morphological datasets showed no distinct shape variations across the right paramere, left paramere, median pygophore process, and lateral phallothecal sclerite among the examined specimens. Based on the congruence between the molecular and morphometric results, P. turpissyn. nov. and P. fulvescenssyn. nov. are formally treated as the junior synonyms of P. atromaculatus in accordance with the Principle of Priority in zoological nomenclature, as P. atromaculatus is the oldest available name among the three taxa. A revised and comprehensive redescription of P. atromaculatus incorporating these color variations is provided.