The genera Agathocles and Surenus (Hemiptera: Heteroptera: Pentatomidae): tribal reassessment, redescription, new synonyms, and description of two new species

Abstract

The genus Surenus Distant, 1901 (Hemiptera: Heteroptera: Pentatomoidea: Pentatomidae: Pentatominae: Halyini) is revisited and found to be a junior subjective synonym of the genus Agathocles Stål, 1876 (currently Pentatominae: Rolstoniellini). The genus Agathocles and its type species, Agathocles limbatus Stål, 1876, are redescribed. Lectotype of Surenus normalis Distant, 1901 (= Agathocles normalis (Distant, 1901) comb. nov.) is designated and the unknown male of the species is described. Agathocles yunnanensis Zhang & Lin, 1984, syn. nov., is considered junior subjective synonym of A. limbatus. Two new species are described: Agathocles flavipes sp. nov. from India (Andhra Pradesh, Karnataka, Maharashtra, and Tamil Nadu) and A. joceliae sp. nov. from Malaysia (Kelantan, Perak). The new species differ from their congeners mainly by the morphology of mandibular plates, length of antennomeres I, IIa and IIb, body length, and structure of male genitalia. Agathocles dubius Distant, 1921 is transferred to the genus Caystrus Stål, 1861 (Pentatominae: Caystrini) based on examination of its holotype with the resulting new combination: Caystrus dubius (Distant, 1921), comb. nov. One new combination is proposed, Paramecocoris ruficornis (Fieber, 1851), comb. nov. (from preoccupied Paramecus Fieber, 1851), and its type locality is clarified as Tenasserim (south Myanmar). Gender agreement and authorship of the name Riazocoris niger Ahmad & Afzal, 1977 in Ahmad et al. (1977: 161) are corrected and status of its name bearing type is clarified as lectotype. The following new distribution records are given: A. limbatus from Cambodia, China (Guangxi, Tibet), Laos and Thailand, A. normalis, Caystrus obscurus (Distant, 1901a) and Critheus lineatifrons Stål, 1869 from Laos, Amasenus corticalis Stål, 1863 from Cambodia, Indonesia (E Kalimantan), Laos, Myanmar and Thailand, and Rolstoniellus boutanicus (Dallas, 1849) from Vietnam. Based on characters of external morphology and genitalia, the genus Agathocles is compared with representatives of the genera Halys Fabricius, 1803 (Halyini), Caystrus (Caystrini), Laprius Stål, 1861 (Myrocheini), and Exithemus Distant, 1902 (currently in Rolstoniellini). As a result, the genus Agathocles is here transferred to the tribe Caystrini. The genus Kyrtalus Van Duzee, 1929 is tentatively placed in Myrocheini based on the presence of sulcate mesosternum and femora provided with teeth.

Opening Pandora's box: molecular phylogeny of the stink bugs (Hemiptera: Heteroptera: Pentatomidae) reveals great incongruences in the current classification

“…The Halyini has been mentioned as one of the most difficult tribes to define (Gross, 1976;Wall, 2007;Kment, 2013;Rider et al, 2018). Members do not possess clear synapomorphies and their structures are extremely variable, probably derived from the fact that some genera are misplaced in the tribe (e.g., Agathocles Stål and Surenus Distant, see Salini & Kment, 2021). The general habitus is quite defining (Gross, 1975a), and includes: general dark colouration; the head and body are elongated, with associated appendices usually proportionally longer; the lateral margins of the head and pronotum are often foliate, dentate, or crenulate; the femora are sometimes armed with small teeth or spines; the peritreme is variable; the prosternum is usually weakly sulcate, the mesosternum is medially carinate, and the metasternum is usually flat to shallowly concave; and the ventral abdomen may or may not be sulcate, short, or continue for most of the length of the abdomen, and the base of the abdominal venter is unarmed (Rider et al, 2018).…”

Revision of Acesines Stål and Dunnius Distant, resurrection of Mycterizon Breddin (Hemiptera, Heteroptera, Pentatomidae, Pentatominae), and description of a new species from India

“…Terminology of general morphology follows Tsai et al (2011) and Salini and Kment (2021) , specialised terms follow the following papers: antennomeres ( Zrzavý 1990 ) and superior processes of dorsal rim ( Roell et al 2020 ). Terminology of male and female genitalia follows Tsai et al (2011) and those associated with the metathoracic scent glands follow Kment and Vilímová (2010) .…”