Plagiomimicus incomitatus Mustelin

Crabo, Lars G., Hammond, Paul C., Mustelin, Tomas & Wikle, David L., 2018, Six new species and one new subspecies of noctuid moths from western United States of America and Mexico (Lepidoptera, Noctuidae), ZooKeys 788, pp. 201-239 : 214-217

Plagiomimicus incomitatus Mustelin sp. n. Figs 15, 16, 20, 23, 49

Type locality.

Mexico, Baja California Sur, 11.3 km south of Punta Colorada.

Type material.

Holotype, male. Mexico, Baja Ca Norte [sic] [Baja California Sur], 7 miles [11.3 km] south of Punta Colorada, (arroyo), 23-30 XII, 1987, N. Bloomfield / USNM [genitalia slide] 46113. SDMC. Paratypes. 6 m, 3 f. Mexico: Baja California Sur: same locality, date, & collector as holotype (5 m 1 f); Same data, [genitalia slide] TM#465 (1 m); same data, [genitalia slide] USNM 46114 (1 f); Punta Colorada, 22 XII 1987, N. Bloomfield (1 f). CNC, SDMC, TM, USNM.

Differential diagnosis.

Plagiomimicus incomitatus (Figs 15, 16) can be recognized by the combination of small size (FW length 11-13 mm), pale yellow tan color, undulating brown forewing transverse lines, and S-shaped forewing outer margin with pointed apex. It is the only species in the P. tepperi species-group that has a large indistinct dark reniform stigma. Males (Figure 20) have short peg-like ampullae similar to those of P. yakama , but these are thicker in P. incomitatus . Females of P. incomitatus (Figure 23) are distinguished by having a long corpus bursae with a strong bend, but are best identified by forewing shape and maculation.

Plagiomimicus incomitatus has not been barcoded.

Description.

Adult. Males and females similar in habitus. Head. Antenna simple, venter finely setose, dorsal scales ochre. Scape pale ochre, ventral tuft short. Eye normal. Labial palpus reaching top of eye; first 2 segments long, short distal segment angled 45° rostrad; scales ochre. Haustellum normal. Frons scales tan; frontal process similar to P. yakama , central cone slightly longer. Dorsal head scales ochre. Thorax. Dorsal scales flat, bases moderately narrow, edges finely toothed, ochre, many with tan tips; patagium scales similar, slightly darker; tegula scales similar, many tan gray distally; entire dorsal thorax appearing similar to dorsal forewing; venter scales hair-like, ochre off-white. Legs: Foretibia apical spine short, thin; tarsal segments except apical segment with three regular rows of spiniform setae; scales tan. Wings: Forewing: length 11.0-12.5 mm (male), 12.0-13.0 mm (female); length 1.65 × maximum width. Apex acute, outer margin S-shaped, concave opposite cell, convex M3-CuA2. Dorsum: Scales mixed light to dark ochre and gray tan; appearing golden tan with dark dusting on costa, along veins (particularly Cu), and posterolateral medial, subterminal, and terminal areas (darkest in females), a gray-brown band in distal terminal area at concave margin; subapical spot tan, faint; basal and medial lines absent; antemedial and postmedial lines brown and cream, dark component bordering medial area; antemedial line smoothly undulating, convex at cell and fold, concave on mid-wing, angled slightly basad from costa to posterior margin; postmedial line adjacent to subapical spot pale, strongly angled distad, bent acutely basad at posterior subapical spot, thence smoothly S-shaped to posterior margin, convex from subapical spot to Cu, concave thence to posterior margin; subterminal line cream, evident mostly due to dark adjacent scales, evident adjacent to subapical patch and from M2 to posterior margin, latter segment S-shaped, parallel to postmedial line; terminal line, orbicular and claviform stigmata absent; fringe medium grayish tan, base ochre; reniform stigma brown, oval, diffuse. Hindwing: Lateral margin opposite cell weakly concave; ground color paler than forewing, whitish, dusted heavily with grayish tan scales (especially in females), darkest medial to postmedial line and near margin; discal spot diffuse, pale gray, elongate, C-shaped; postmedial line diffuse, light brown gray, anterior ⅓ perpendicular to costal margin, posterior segment perpendicular to medial margin, touching posterior discal spot; terminal line brown gray, darkest at concave margin; fringe gray off-white. Abdomen. scales flat, dorsum ochre tan, venter lighter. Male genitalia: Uncus arced, base thick, width 0.33 × length, tapered from mid-section to thin acute point. Juxta broad shield shape, height 0.67 × width. Valve flaplike, ovate, length 2.5 × width, cucullus unmodified, pointed bluntly, corona absent; sacculus 0.67 × valve length and 0.4 × width, basal process, short, triangular, median sacculus with dorsal obtuse triangular projection, shorter (1 specimen) or similar length (1 specimen) to basal process; ampulla of clasper short, 0.11 × valve width, right slightly longer and stouter than left (1 specimen) or much stouter than left (1 specimen), origin near ventral valve at end of sacculus, oriented 45° dorsad and distad to valve. Phallus tubular, length 4.5 × width; vesica length 0.7 × phallus length, width 1.5 × phallus width, bent 90° at base, bearing single median patch of numerous stout spine-like cornuti directed basad, basal cornuti absent. Female genitalia: Papilla analis conical, apex acute. Segment A8 length 1.2 × width. Posterior apophysis length 1.5 × segment A8; posterior apophysis 0.5 × anterior apophysis. Ductus bursae short, length 0.4 × segment A8, expanded slightly anterior to slight constriction at posterior origin; ostium bursae broad, funnel shaped. Corpus bursae elongate, length 2.8 × segment A8, slender, width 0.2 × length, anterior segment widest distal to 60° bend; appendix bursae extended posterior from broad junction to corpus bursae at junction with ductus, moderately sclerotized; ductus seminalis at ventral apex.

Etymology.

Incomitatus is Latin, meaning “unaccompanied” or “alone.” It refers both to the single known locality for this species as well as the solitude of its collector, Norris Bloomfield, during long collecting trips on behalf of SDMC in Baja California in the late 1980s.

Distribution and ecology.

Plagiomimicus incomitatus is only known from the type locality near the southern tip of the Baja Peninsula, Mexico (Figure 49). The habitat is a dry arroyo in Baja desert. All specimens were collected with black light in late December. The early stages are unknown.

Discussion.

Plagiomimicus incomitatus is classified in the P. tepperi species-group based the lack of the corona and basal patch of cornuti in the male genitalia. It resembles the other species in the group.

The moth fauna of the Baja Peninsula is poorly known, especially compared with that of adjacent southern California. Of what is known, much is due to Norris Bloomfield who made several collecting trips to the area during the 1980s on behalf of the San Diego Natural History Museum. Although the majority of the Noctuoidea collected by him also occur in southern California, he also encountered many species that are only known from southern parts of Arizona, New Mexico, or Texas, as well as some not known from the United States. Plagiomimicus incomitatus is one of the latter species, currently only known from the type locality. The apparent rarity of this moth might be due the lack of collecting in this region as well as its late December flight period.