Achagua Rindge, 1983

Matson, Tanner A., 2023, The known species of the genus Achagua Rindge, 1983, with the description of three new species from the Neotropics (Geometridae: Ennominae), Zootaxa 5352 (4), pp. 565-576 : 566-567

Achagua Rindge, 1983

Type Species: Achagua obsoleta Rindge, 1983 ; original designation.

Re-diagnosis. Both Rindge (1983) and Pitkin (2002) provided diagnostic comments for Achagua , but with the discovery of three undescribed species, it is necessary to revisit these diagnoses. The mostly bipectinate antennae of male Achagua , with the apical third to quarter being simple filiform, is a shared characteristic among related nacophorine genera, e.g., Cargolia and Gabriola, and thus, does not disambiguate closely related taxa. In males, the two processes of the uncus in conjunction with the subtriangular anellar processes appear to be the most reliable diagnostic features ( Figs. 5a, 6a, 7a, 8a ). Pitkin (2002) listed the strongly spatulate (or capitate) dorsal process of the uncus as an apomorphy for the genus, but two of the new species described herein possess a non-spatulate dorsal process ( Figs. 7a, 8a ). In females, the large, elongate, apically pointed, denticulate signum may be diagnostic, but only a single preparation of A. obsoleta ( Fig. 9 ) and two preparations of A. cooperae ( Fig. 10 ) were available for study. Superficially, the pearly-white ground color, large size, brown to black wing margins, and lack of welldefined antemedial and postmedial lines seem to also define Achagua . Further, the multi-locus phylogenetic results of Murillo-Ramos et al. (2019) and Brehm et al. (2019) also support the recognition of Achagua as distinct from related genera.

Distribution ( Fig. 11 ). Achagua inhabit the tropical and subtropical moist broadleaf forests of Central and South America from the Sierra de los Tuxtlas of Veracruz, Mexico ( A. cooperae ), east to the Guiana Highlands ( A. velata ), and southward through the eastern Andes of Colombia, Ecuador, and Peru to at least the Bolivian Yungas ( A. magna ).

Biology. Thus far, no life history information is known for the genus. Adults are infrequently collected at light.

Remarks. In Achagua , the uncus is characterized by two distinct processes. However, there is some disagreement regarding the nomenclature of these processes. Rindge (1983) referred to the much larger dorsal process as the pseudouncus, but it is unclear how he arrived at this conclusion. Alternatively, I adopt the terminology used by Pitkin (2002) and refer to these processes based on their orientation, specifically as the dorsal or ventral processes of the uncus.

Campos (2001) described the genus “ Achagua ” for a group of freshwater crabs. As the name was already preoccupied by Achagua Rindge (the subject of this work), “ Achagua ” Campos was rendered a junior homonym. Campos and Magalh„es (2004) synonymized “ Achagua ” Campos with Eudaniela Pretzmann , such that this junior homonym has not been in contemporary use.

Figures

FIGURE 11. Geographic distribution of Achagua: A. obsoleta Rindge (star), A. magna n. sp. (triangle), A. cooperae n. sp. (circle), and A. velata n. sp. (square). Single dots may represent>1 individual. Scale bar = 600 km.

FIGURES 5–8. Achagua male genitalia. (a) genital capsule, (b) phallus. (5) A. obsoleta Rindge, TAM-2023-270, AMNH_IZC 00353009, paratype, AMNH; (6) A. magna n. sp., TAM-2023-268, AMNH_IZC 00353023, paratype. AMNH; (7) A. cooperae n. sp., TAM-2023-251,AMNH_IZC 00353028, paratype, AMNH; (8) A. velata n. sp., TAM-2023-289, holotype, MNHN. Scale bar = 2 mm.

FIGURES 9–10. Achagua female genitalia. (9) A. obsoleta Rindge, No. 20288, NHMUK010293435, NHMUK; photo credit: Louise Berridge (NHMUK); (10) A. cooperae n. sp., TAM-2023-276, USNMENT01771269, paratype, USNM. Scale bar = 2 mm.