Neomacrocoris angusticeps (Haglund)

Sites, Robert W. & Mbogho, Aaron Y., 2012, Revision of the African genus Neomacrocoris (Hemiptera: Heteroptera: Nepomorpha: Naucoridae), Zootaxa 3555, pp. 1-39 : 5-6

Neomacrocoris angusticeps (Haglund)

Macrocoris angusticeps Haglund 1895 : Öfv. Kongl. Vet.-Akad. Förh. 7: 477–478. Neomacrocoris angusticeps: Montandon 1913 , Bul. Soc. Rom. Stiinte, 22: 332.

Discussion. The type specimen is a male from Cameroon ( Poisson 1948 ) and was reported to be 10 mm long by 6.4 mm across the abdomen ( Haglund 1895), but it has disappeared from the Naturhistoriska Riksmuseum in Stockholm ( Poisson 1948 ). We received recent confirmation that the specimen still is missing and that the unit box houses an empty pin and a label with the number 11, suggesting that the specimen was loaned in the 1930s (J. Bergsten, pers. com.). Haglund (1895) compared this species with Macrocoris flavicollis Signoret and said that it is related but less convex. Similarly, in the original description of Macrocoris convexus, Montandon (1897) compared N. angusticeps with it and indicated that N. angusticeps is of the same size but much less convex and more widened. Although he was unable to examine the type specimen, Poisson (1948) provided illustrations of the 7th and 8th abdominal terga and aedeagus of a Montandon-determined specimen from Boma, Democratic Republic of Congo, and considered the male to be similar to that of N. handlirschi armatus Poisson because of the presence of denticles; but the taxa differ in the condition of the pseudostrigil and lobes of the 8th tergum. Housed at the USNM is a Poisson slide with 7th and 8th terga from Belgian Congo, and one adult male specimen from the Poisson acquisition with a provisional identity of N. angusticeps . This male has identical label data with a female housed in RMCA also identified provisionally as N. angusticeps by Poisson , as well as with the type specimen of N. vaneyeni Poisson. Characteristics of the slide-mounted terga including the pseudostrigil are nearly identical with those of N. vaneyeni with the exception of a series of denticles on the underside of the left mesal lobe of the 7th tergum. The aedeagus was not present. We dissected the male and found the lobes of the 7th and 8th terga and phallosoma to be consistent with those of N. vaneyeni . Because we have observed substantial intraspecific variation in condition of the left lobe of the 7th tergum in congeners and Poisson (1948) even commented on intraspecific variation in the number of denticles, and established subspecies of N. handlirschi based on presence or absence of these denticles, we consider Poisson’s concept of N. angusticeps actually to represent N. vaneyeni . Poisson’s concept of the lost Haglund type is based secondarily on Montandon’s concept of the species. Thus, to base a current concept of N. angusticeps on Poisson in the absence of the type or other authoritative specimens would be three times removed from the original concept. We feel that this would require making unacceptably risky assumptions about the species. As such, the identity of N. angusticeps remains enigmatic and specimens should be searched for in the broadly defined type locality of Cameroon. If it is determined in the future that N. angusticeps and N. vaneyeni are conspecific, N. vaneyeni would become a junior synonym of N. angusticeps .

Diagnosis. Based on information in the original description, this is among the larger species at 10 mm in length; however, at only 6.4 mm width, it apparently does not fall within the group of ovate species ( N. karimii , N. vaneyeni , and N. vuga ).

Published Records. BELGIAN CONGO ( Montandon 1897), CAMEROON ( Haglund 1895).