NAUCORINI POPOV, 1970

Sites, Robert W., 2022, Phylogeny and revised classification of the saucer bugs (Hemiptera: Nepomorpha: Naucoridae), Zoological Journal of the Linnean Society 195, pp. 1245-1286 : 1271

TRIBE NAUCORINI POPOV, 1970

FIG. 10H

Diagnosis: As has been the dilemma with the previous concept of the subfamily Naucorinae , apomorphic characters to define the tribe as considered here are not evident. The dramatically asymmetrical parameres are consistent with all other tribes in Naucorinae . It lacks the relatively broad left paramere without a pronounced lobe on the left side which is characteristic of Idiocarini . It lacks the anteromedial tooth of the prosternum, which is characteristic of all but one member of Asthenocorini .

Comments: The major clade at the root of Naucorinae includes two species of Naucoris and two populations of the closely related Thurselinus scutellaris , and forms the tribe Naucorini . Although most treatments have considered the species as Naucoris scutellaris, Zettel (2001) resurrected Distant’s (1904) genus Thurselinus in which to place N. scutellaris based on connexival corner shape and paramere condition. Naucoris maculatus is the nominate species of the family and its relationship with Thurselinus renders the clade paraphyletic in this topology; thus, Thurselinus is here re-synonymized with Naucoris as originally described by Stål (1860). Further, the two specimens identified as N. scutellaris are from Australia and Thailand and are of sufficient molecular evolutionary distance that they apparently are not conspecific. The population from Australia was first described as Naucoris rhizomatus Polhemus, 1984 , but was later synonymized with N. scutellaris ( Polhemus & Polhemus, 2013) . Because the type locality for the species is Java, it is uncertain if either the Australian or Thai specimens represent actual N. scutellaris . Comparison with material from Java is needed to determine appropriate name changes. Assuming the Australian and Thai specimens included in the analysis here are not conspecific, one of three nomenclatural scenarios is possible: the Thai population is unique and should be described, N. rhizomatus should be reinstated as a valid species as originally described, or both if neither population is conspecific with N. scutellaris from Java. Further complicating the identity of N. scutellaris is that Shruti Paripatyadar (Pune, India) has populations of putative N. scutellaris from Maharashtra with the typical spined left paramere but with a right paramere that differs. Also, N. scutellaris has been recorded from the Philippines and also has the spined left paramere ( Zettel, 1999 ). Thus, it seems that the widespread N. scutellaris might be a complex of cryptic species. If so, several synonyms exist that might be available for Indian and Sri Lankan species ( Lundblad, 1933).

Included taxa: The distribution of N. maculatus is Palaearctic, N. scutellaris and N. sigaloeis are Southeast Asian, N. rhizomatus is Australian and five additional species of Naucoris have not been mentioned above. Because of the apparent vagility of the ancestral stock and precarious action of assigning these additional five species to groups without compelling non-molecular evidence, the following are not treated here and are incertae sedis: Naucoris acuta Spinola, 1837 , Naucoris minutus D. Polhemus & J. Polhemus, 2013 , Naucoris obscuripennis Stål, 1854 , Naucoris pumilus Zettel, Nieser & D.Polhemus, 1999 and Naucoris sumatranus Fieber, 1851 . The identity of N. acuta is unknown because the eleven-word original description and lack of authoritatively determined specimens render the species unrecognizable based on available information, thus this is a species inquirenda. Figures in the original description of N. minutus , and descriptions of N. obscuripennis and N. pumilus (see Zettel, 1999 ) show a lobe on the left side of the left paramere. These species are therefore not members of Idiocarini . A female lectotype of N. sumatranus was designated based on the only remaining specimen from the type series ( Zettel, 2011 ), if more than one specimen ever existed, thus male genitalia are not available for this species. Additional research is needed to determine proper taxonomic placement of these five species.

Figures

Figure 10. Habitus examples of each subfamily: Ambrysinae: Ambrysus signoreti (a), Cheirochelinae: Cheirochela thailandana (b), Cryphocricinae: Cryphocricos hungerfordi (c), Ilyocorinae: Ilyocoris cimicoides (d), Laccocorinae: Laccocoris limicola (e), Limnocorinae: Limnocoris inornatus (f), Macrocorinae subfam. nov.: Macrocoris flavicollis (g), Naucorinae: Naucoris scutellaris (Thailand) (h).