Plagiomimicus yakama mojave Wikle & Crabo

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 : 211-214

Plagiomimicus yakama mojave Wikle & Crabo ssp. n. Figs 12, 13, 18, 24, 49

Type locality.

USA, Arizona, Mohave County, Hualapai Mountains, 9.7 km west of Wikieup.

Type material.

Holotype, male. USA, Arizona, Mohave County, 34°40.478'N, 113°41.934'W, Hualapai Mts., 6 mi [9.7 km] W of Wikieup, 10 IX 2013, leg. D. L. Wikle, to MV / DLWC 011176 / Specimen ID CNCLEP 00116215 / Barcodes of Life Project, Leg removed, DNA extracted. CNC. Paratypes. 37 males, 6 females. USA: Arizona: Mohave County: Hualapai Mts, 6 mi [9.7 km] W Wikieup, 34°40.212'N, - 113°42.299'W, elev 3590' [1094 m], 19 IV 2012, to B[lack] L[ight], D. L. Wikle leg. / DLWC011081 / [Crabo genitalia slide] 615 male / DNA CNCLEP 00116338 (1 m); same locality and collector as holotype, 9 V 2010 / DLWC011153 (1 m), DLWC011273 (1 m); same locality and collector, 5 IX 2012 / DLWC011018 (1 m), DLWC011039 / DNA CNCLEP 00116337 (1 m), DLWC011034 (1 m), DLWC011180 / DNA CNCLEP 00116336 (1 male), DLWC011187 (1 f), DLWC011262 (1 m), DLWC011298 (1 m), DLWC011342 (1 m), DLWC011350 (1 m), DLWC011377 (1 f); same locality and collector, 10 IX 2013 / DLWC 011126 (1 m), DLWC011291 / Specimen ID CNCLEP 00116216 / Barcodes of Life Project, Leg removed, DNA extracted (1 f), DLWC011370 (1 m); Hualapai Mts, Wikieup 9 km WSW, 34.674°, -113.699°, 1060 m, 14 IV 2015, L. G. Crabo leg. / DNA CNCLEP 00116339 (1 m); Nevada: Clark County: Charleston Mts, Kyle Canyon, 26 IV 1950; E. C. Johnston (12 m), Genitalia Slide, By PG, USNM 45696 (1 m), Genitalia Slide, By PG, USNM 45697 (1 m); Spring Mts, Lucky Strike Canyon Rd., 36°18.061'N, - 115°29.441'W, elev. 4885' [1489 m], RRCNCA #NV-052, to BL/MV, 21 IV 2013, leg. D. L. Wikle / DLWC011299 (1 f); same locality and collector, 12 V 2013 / DLWC011294 (1 f); Utah: Garfield County: Old Sheffield Rd off Hwy 12, 37°43.376'N, - 111°26.266'W, elev. 6005' [1830 m], 5 V 2009, leg. D. L. Wikle / DLWC011035 / Specimen ID CNCLEP 00116214 / Barcodes of Life Project, Leg removed, DNA extracted (1 m), DLWC011099 (1 m), DLWC011118 (1 m), DLWC011123 (1 m), DLWC011243 (1 m), DLWC011246 (1 m), DLWC011264 (1 m), DLWC011347 (1 f); Spencer Flat Rd mi 1.7 [2.7 km] sta 1, 37°43.411'N, - 111°26.273'W, elev. 6015' [1833 m], lt B[lack] L[ight], 11 V 2012, D. L. Wikle leg., GSENM Permit#UT-12-033-01-B / DLWC011201 / [Crabo genitalia slide] 616 male / DNA CNCLEP00116333 (1 m); Wolverine Loop “draw,” 37°49.924'N, - 111°6.535'W, elev. 6440' [1963 m], GSENM #UT-12-033-01-B, leg. Opler + Wikle (1 m). CNC, DLW, LGC.

The type series is restricted to Arizona, Nevada, and Utah.

Differential diagnosis.

Subspecies P. y. mojave (Figs 12, 13) is pale olivaceous ochre tan, appearing paler, yellower, and more “washed-out” than the nominate subspecies. Dark areas of the forewing are tan rather than olive, less contrasting than in P. y. yakama (Figure 11), and the subapical spot is vaguely darker than the adjacent wing if visible at all. Most specimens lack angulation of the postmedial line on the cubital vein resulting in a wider medial area than in P. y. yakama . The antemedial and postmedial lines of darker specimens are two toned, tan on the medial-area side, whereas those of P. y. yakama are pale. The forewing apex tends to be most pointed in this subspecies. No significant genitalia structural differences are evident between the subspecies.

Plagiomimicus y. mojave is most likely to be confused with P. tepperi (Figure 14), the western range of which approaches to within 135 km of P. y. mojave in northwestern Arizona. In addition to structural characters noted in the P. yakama description Plagiomimicus tepperi is distinguished by slightly falcate forewing apex and a dark shade preceding the subterminal line. Differences between P. y. mojave and P. incomitatus (Figs 15, 16) are described under the latter species, though it is unlikely that these moths occur together.

Description.

Adult. Males and females similar in size and habitus. Head. Structure and vestiture similar to P. y. yakama , paler. Thorax. Dorsum pale yellow tan. Wings: Forewing: Length 11.0-14.5 mm; apex more pointed than in P. y. yakama ; scales pale yellow and light tan; uniform pale yellowish tan outside medial area, subterminal area and subapical spot slightly darker in some specimens; medial area darker olivaceous yellow-tan, usually slightly darker on posterior ½; cubital vein slightly lighter basal to postmedial line in some specimens; basal and medial lines absent; antemedial and postmedial lines off-white, bordered by tan in medial area in dark specimens; antemedial line oblique from mid-costa to inner ⅓ of posterior margin, straight; postmedial line similar to nominate subspecies, but slightly convex near cell; subterminal line pale off-white, only visible in dark specimens; terminal line thin, tan, evident on anterior ½; subapical spot indistinct or absent, lighter than medial area when present; fringe same as terminal area; stigmata typically absent, reniform stigma occasionally a bar of few pale scales. Hindwing: Uniform pale yellowish gray, slightly darker on basal ½; fringe off-white. Abdomen. Paler than for P. y. yakama . Male genitalia and female genitalia: as for P. y. yakama .

Etymology.

The name refers to the distribution of this moth in and near the Mojave Desert. It is a noun in apposition.

Distribution and ecology.

This subspecies occurs in the Mojave Desert and southern Great Basin (Figure 49), 1000 km south of nominate P. yakama . Specimens have been examined from Garfield and Kane counties of southern Utah, Clark County of southern Nevada, Mohave County in northwestern Arizona, and east of the Coachella Valley in Riverside County, California. The identity of a few populations of superficially similar moths from west of the Coachella Valley remain uncertain. California specimens are therefore excluded from the type series. The apparent large separation of the ranges of the two P. yakama subspecies could potentially be an artifact related to limited collection in the Great Basin during the spring flight period of this species.

Larvae of P. y. mojave (Fig. 24a, b) have been collected and reared to adults by DLW on Brickellia atractyloides A. Gray in the Hualapai Mountains of Arizona and Brickellia oblongifolia in Nevada. The following description is modified from a work on the larvae of western North American moths (DL Wagner, unpublished):

Ova are placed deep inside the discoid flower heads and the early instars are internal feeders on flowers as they are going to seed. Molting occurs inside the flower head and, as the larvae progress, frass is present externally on some flowers. Larvae leave the flowers as they become spoiled, and later instars rest on stems and seed heads and feed externally on multiple flowers. The early instars are pale with red spotting and a pale supraspiracular stripe.

Penultimate instars (Figure 24a) are similar, but the ground color is green. Red spotting is reduced, remaining most prominent on the thoracic segments. The supraspiracular stripe is better developed.

The last instar is greenish red with well-defined pale mid-dorsal, subdorsal, and lateral stripes. Minute red spots develop diffusely over the course of this stage such that the larva changes from green similar to the penultimate larva initially, to more or less pink through the second half of the instar (Figure 24b). The subdorsal stripe is twice as thick as the mid-dorsal stripe. A faint diffuse supraspiracular stripe extends A1-A8. The lateral (spiracular) stripe begins at A1 and continues to the base of the A10 proleg. The spiracles are black. The primary setae are not borne from white pinacula as in other members of the P. tepperi species-group.

The larvae of P. y. mojave are similar to those of P. mimica , which feeds exclusively on Brickellia californica (Torr. & A. Gray) A. Gray throughout its range. Its larva differs from P. y. mojave in that the lateral stripe is often cream or yellow rather than white, the subdorsal stripe is well developed, the mid-dorsal stripe is thin, and the larva is thickened through the thoracic segments.

Plagiomimicus y. mojave is at least partially double brooded, flying in late spring and again in early fall in areas where food plants flower in the spring and fall.