Laccocorinae STAL 1876
Creators: name: Sites, Robert W.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Naucoridae

description: SUBFAMILY LACCOCORINAE STÅL, 1876
FIGS 3B, 4– 6, 10E, 11E, 12, 14, 15, 20, 21
Type species: Laccocoris spurcus Stål, 1856.
Taxonomic history: Stål (1876) proposed the division Laccocoraria to contain two genera, Heleocoris and Laccocoris, that he described. Montandon (1897b) e l e v a t e d L a c c o c o r a r i a t o s u b f a m i l y s t a t u s a s Laccocorinae. Popov (1970) considered this group as a tribe-level taxon, Laccocorini, within subfamily Naucorinae, but this classification scheme has not been followed by other specialists. Presently, ten genera are recognized in the subfamily, with no suprageneric organization as tribes.
Revised taxonomy: Laccocorinae remains unchanged with respect to constituent species, although synonymies, new genera and tribes are proposed here. In my Most Probable Phylogeny dendrogram (Fig. 9), I substituted the ML topology of the clade sister to Ctenipocoris to represent what I consider to be the most plausible evolutionary relationships in the subfamily. Laccocorinae is represented by four distinct major clades, which are herein recognized as tribe-level taxa (Fig. 13). Two of the predominant genera (Heleocoris and Laccocoris) in the subfamily are polyphyletic and occur in multiple clades in two tribes.
Species of Heleocoris occur in three disparate clades (Figs 13, 14). The type species is Heleocoris obliquatus (Spinola, 1837) from Bombay (Mumbai, India) as designated by Stål (1876), who based his designation on a specimen in the collection of Signoret. Montandon (1910b) questioned the existence of the type specimen, which was based on a brief original description, and provided a redescription of the species based on a specimen in Distant’s collection from the Dawna Hills of eastern Burma. Given that most species in these groups are restricted to particular geographic regions, it is highly doubtful that the specimen upon which Montandon redescribed H. obliquatus was in fact that species. Further vitiating this identification is the figure in Distant (1910: 322) of a specimen from ‘Lower Burma’ identified by Montandon as H. obliquatus, which instead clearly is Heleocoris strabus Montandon, 1897b. As such, H. obliquatus from Mumbai remains enigmatic and nearly impossible to diagnose without an authoritatively identified specimen, and thus is a species inquirenda. Nonetheless, because the type locality was given as ‘Bombay’, I here consider the clade containing species of Heleocoris from central India (all but the far eastern states) to be valid Heleocoris. Other clades containing Heleocoris from Africa and Indochina each must have the genus renamed.
Species of Laccocoris were recovered in two distinct clades within different tribes (Figs 13, 15). The type species is Laccocoris spurcus (Stål, 1856) from Africa; thus, the species of Laccocoris from Africa remain unchanged. However, the species of Laccocoris from Sundaland and the Philippines are here placed in a newly erected genus, Heleolaccocoris gen. nov. Because the well-supported ML topology recovered Heleolaccocoris as sister to three species of Indochinese Heleocoris in successively more inclusive clades, this necessitated either designation of additional genera to accommodate the clades of Indochinese Heleocoris, or placing them all in Heleolaccocoris as I have done here (Fig. 13: bluecoloured clades). The previously recognized distinction between the two genera (Heleocoris and Laccocoris) was based on the shape of the labrum as wider than long with a rounded apex or longer than wide with an acute apex. This has been generally considered a feature inconsistent with phylogeny by recent scientists who have studied the group. In a treatment of the Naucoridae in Singapore, Polhemus & Polhemus (2013) considered the generic limits of Heleocoris and Laccocoris to be indistinct and correctly predicted the possible synonymy of Asian Laccocoris with Heleocoris.
Diagnosis: This subfamily has a suite of unique diagnostic attributes, some of which exhibit variation among genera. The front of the head is folded posteroventrally such that the labrum is set back from the functional anterior margin of the head (Fig. 3b). Males of all genera have a dense tomentose pad ventrally over much of the mesotibia and tarsomeres 2 and 3 (Fig. 12), and to a lesser extent the protibia and tarsus, whereas in females the pads are greatly reduced. The prothoracic pretarsal claws are paired and articulated, except in Namtokocoris in which they are single and fused with the tarsus, which is the condition found in all other subfamilies (Fig. 4c). Males have two-segmented front tarsi and females only one, except in Ctenipocoris where both sexes have two, and in Namtokocoris and Pogonocaudina where both sexes have one (Fig. 4).
Comments: This subfamily is circumtropical in distribution and is most common in Africa and Asia. It is not known from Australia. Although Ctenipocoris is circumtropical in distribution, each of the other major clades in the subfamily has a distinct geographic association.
description: Published as part of Sites, Robert W., 2022, Phylogeny and revised classification of the saucer bugs (Hemiptera: Nepomorpha: Naucoridae), pp. 1245-1286 in Zoological Journal of the Linnean Society 195 on pages 1262-1264, DOI: 10.1093/zoolinnean/zlab105, http://zenodo.org/record/6994599