Stamnodes erupta Matson 2023, sp. nov.
Creators: name: Matson, Tanner A.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Geometridae
Stamnodes
Stamnodes erupta

description: Stamnodes erupta sp. nov.
urn:lsid:zoobank.org:act: 461F7E96-F1B3-4BEC-A0BF-9BF90C74F602
Figs 16, 51, 69, 82, 95
Diagnosis
Stamnodes erupta sp. nov. may be confused with S. fervefactaria, S. fergusoni, S. disrupta sp. nov. and S. mariachi sp. nov. The bright, white reticulate pattern of the underside of the hindwing and apex of the forewing stand in contrast to the more off-white to cream colour of the same areas in S. fervefactaria. Additionally, the lead grey patches on the hindwing underside are finely bounded by a thin dark grey edge in S. fervefactaria and S. fergusoni that is absent in S. erupta. Stamnodes erupta is known from the vicinity of Mexico City, while Stamnodes disrupta is so far only known from the northern Sierra Madre Occidental in the states of Sonora and Chihuahua. While the hindwing underside of S. erupta bears a straight, white, transverse medial band that angles toward the tornus (see left arrow, Fig. 16b), the same band in S. disrupta gradually curves toward the tornus (see left arrow, Fig. 14b). The angle of this band affects the shape of the large lead-coloured patch near the tornus; in S. erupta, it is more triangulate, while in S. disrupta, it is more subovate. Additionally, the basal inner margin of S. erupta lacks the white scaling along the inner edge of the large grey patch of the same area found in S. disrupta (see right arrows, Figs 14b, 16b). Stamnodes erupta can be separated from S. mariachi by the presence of a checkered forewing fringe and oblique white patch in apical area of forewing underside.
Male genitalia readily separate S. erupta sp. nov. (Fig. 51) from S. fergusoni (Matson & Wagner 2020: fig. 7). Stamnodes fergusoni has a juxta that bears posterolateral conical processes and its vesica has a large echinate patch of cornuti; these characters are absent in S. erupta. However, the male genitalia of S. disrupta sp. nov., S. fervefactaria, S. erupta, and S. mariachi sp. nov. are exceedingly similar with only subtle differences. While the uncus of S. disrupta (Fig. 49a) and S. fervefactaria is broadly swollen medially, that of S. mariachi (Fig. 50a) and S. erupta (Fig. 51a) tapers only slightly along its length and is not noticeably swollen medially.
Etymology
The species name erupta was inspired by the moth’s striking colouration, which to an imaginative eye, may resemble the explosive eruption of a volcano. It is derived from the Latin verb ‘ erumpere ’, meaning ‘to break out’ or ‘to burst forth’.
Material examined
Holotype
MEXICO • ♂; [Mexico City], nr City Mex.; [19.6° N, 99.1° W]; August; R. Muller leg.; 8664; genitalia: TAM-2023-258 (USNM 154209); USNMENT01771245.
Paratypes (6 ♂♂, 2 ♀♀)
MEXICO • 2 ♂♂; [illegible pencil writing]; Draudt 1924; Dognin Collection; genitalia: TAM-2023-257 (USNM 154210); USNMENT01771246, USNMENT01771247. – México • 1 ♀; 7 air km WSW of Juchitepec; [19.16° N, 98.90° W]; 24 Aug. 1987; J. Brown and J. Powell leg.; genitalia: TAM-2023-286 (USNM 154212); USNMENT01771228 • 1 ♂; same collection data as for preceding; 25 Aug. 1987; J. Brown and J. Powell leg.; AMNH _ IZC 00353018 • 1 ♂; same collection data as for preceding; CNIN • 2 ♂♂, 1 ♀; 7 air km WSW of Juchitepec; [19.16° N, 98.90° W]; 24 Aug. 1987; J. Brown and J. Powell leg.; EMEC1748445 to EMEC1748447.
Description
Male
FOREWING LENGTH. 17–18 mm (n = 7).
HEAD. Antenna filiform, fuscous to black. Vertex scarlet; frons mostly fuscous, with a few white scales and white along ventral and lateral margins. Labial palpus short, slightly porrect, subequal to diameter of eye, fuscous and white. Cephalic collar mostly scarlet.
THORAX. Patagium mostly scarlet; tegula scarlet at base but otherwise mostly fuscous transitioning to lighter grey distally. Mesothorax fuscous above, white and pink below. Legs mixture of white and fuscous; tibial spur formula 0–2–4; epiphysis well developed.
FOREWING. Scarlet near base, diffusing to light orange-yellow ground colour. Costa with large, trigonate to subquadrangular, costomedial, lead-black patch. Apical area broadly lead-black; sometimes with subtle oblique, patch of ground colour. Underside similar to upperside, but scarlet base more intense in costal area, and costal area given toward white between lead-black costomedial patch and apical area; apical area also with thin, oblique white patch. Fringe lightly checkered.
HINDWING. Concolourous with forewing above, but ground colour mostly reduced to medial, longitudinal ray between large, ill-defined, lead-black coloured patches (Fig. 16a). Underside sharing similar pattern elements, but much more starkly contrasted with white rays between large, lead-black coloured patches; patches along costal antemedian and postmedian, basal half of inner margin, and at tornus (see Fig. 16b). Tornal patch trigonate. Fringe as in forewing.
ABDOMEN. Fuscous.
GENITALIA (Fig. 51). Uncus long, narrow, and tapering toward apex. Subscaphium well developed. Inner surface of valva with dense hair tuft arising from basal tubercle. Juxta shield-like with posterior surface medially depressed; void of stiff setae. Vesica without large cornuti, but with extremely small rugose papillae and needle-like cornuti at base of vesica; rugose papillae also along ovoid lateral diverticulum. Female
Outwardly undifferentiated from male.
FOREWING LENGTH. 18–19 mm (n = 2).
GENITALIA (Fig. 69). Apophyses girthy; anterior apophysis two-thirds length of posterior apophysis. Ostium large, lamella antevaginalis strongly sclerotized. Short and narrow ductus bursae with prominent anterior sclerite flattened on ventral surface and dorsolaterally rolled toward median. Corpus bursae spherical; bearing two signa, each with inward directed process; one signum situated near posterior base of corpus bursae (near ductus bursae) and second near anterior third, each covered with minute papillae.
Distribution (Fig. 82)
Mexico: So far as known, Stamnodes erupta sp. nov. is a denizen of the pine-oak woodlands of the Trans-Mexican Volcanic Belt.
Biology
Stamnodes erupta sp. nov. is known to fly in August. The immature stages remain unknown but are likely hosted by mints (Lamiaceae).
Molecular characterization
This species has not been sequenced.
description: Published as part of Matson, Tanner A., 2023, A review of Mexican Stamnodes (Lepidoptera: Geometridae) with the description of 16 new species, pp. 1-79 in European Journal of Taxonomy 911 on pages 35-37, DOI: 10.5852/ejt.2023.911.2371, http://zenodo.org/record/10376790