Pleurota illucidella Chrétien, 1915 (Chretien, 1915)

Tabell, Jukka, Wikström, Bo, Mutanen, Marko, Bruckner, Harald & Sihvonen, Pasi, 2021, Subspecies of Pleurota bicostella (Clerck, 1759) revisited and descriptions of nine new species in the P. bicostella species group (Lepidoptera: Gelechioidea Oecophoridae: Pleurotinae), Zootaxa 4941 (4), pp. 451-486 : 464

Pleurota illucidella Chrétien, 1915 stat. rev.

Barcode Index Number: BOLD:ADR8160

Table 1, Figs. 9–11 , 38 , 55 , 65 , 66

Pleurota illucidella Chrétien, 1915: 336 . Type locality: Tunisia: Gafsa. Holotype ♀ (MNHNP; examined from photographs). Originally described as a species, lowered to subspecies by Back (1973). Here elevated again to species level based on differential features in habitus, genitalia structure and DNA barcode (stat. rev.)

Material examined. 1 ♀ (GP 5766 J. Tabell, DNA sample 24833 Lepid Phyl [barcoding failed]), Tunisia, Atlas mnts, 15 km NE Makhtar village, conifer forest, 1000 m, 3.V.2000, K. Nupponen leg. (coll. NUP); 1 ♂ (GP 6021 J. Tabell, DNA sample 26140 Lepid Phyl) , 1 ♀ (GP 5917 J. Tabell, DNA sample 26141 Lepid Phyl ), Tunisia, 13.5 km ESE Maktar, 810 m, N35.8022 E9.3386, 7.V.2018, J. Tabell leg. (coll. TAB) .

The genitalia are illustrated and described by Back (1973), but the drawing of male genitalia belongs to some other species, probably to P. lepigrei . Only the corpus bursae with signa is illustrated for the female genitalia, but the characteristic crescent-shaped anterior signum together with the coloration of the adult, enables a plausible identification.

Diagnosis. Externally P. illucidella is somewhat similar to P. dalilae , but the forewing is slightly darker, due to irroration of blackish brown scales. The strongly concave ventral margin of valva, and finger-shaped valval lobe in the male genitalia are distinguishing details. In the female genitalia, the shape of the proximal margin of segment 8 and anterior signum are distinctive.

Molecular data. Two specimens of illucidella were sequenced successfully, resulting in 658 and 637 bp barcode sequences. The sequences are 6.29 %–10.55 % divergent from the other barcoded taxa of the bicostella species group ( Table 1). The nearest neighbour to illucidella is P. kullbergi with a 6.29 % divergence. The divergence between illucidella and bicostella is 8.68 %. The barcodes of illucidella exhibit no intraspecific variation.

Description. Adult. Wingspan 16.6–18.0 mm. Labial palpus off-white, ventrally brown, mixed with white, 6.9 x as long as diameter of eye (1 st and 2 nd palpomeres), 3 rd palpomere 0.27 x length of 1 st and 2 nd palpomeres. Antenna brown. Head, thorax and tegula off-white, mixed with pale brown. Forewing off-white, mixed with pale ochre, pale grey and pale brown scales, small but distinct discal and discocellular spots formed of dark brown scales, plical streak distinct, in outer 0.5 indistinct brown longitudinal streaks, fringe line distinct; costal line white, from near base to 0.8; subcostal line brown, slightly expanded towards apex. Fringe off-white, with subapical pale grey line. Hindwing pale grey, fringe pale grey, apically white. Abdomen pale grey, slightly lustrous, each segment with a transverse row of ochre scales.

Male genitalia. Uncus triangular from ventral view, slightly longer than gnathos, covered with several long and short bristles, apex with finger-shaped protuberance. Gnathos funnel-shaped from ventral view, evenly tapered towards apex, apical half surfaced with scobination, apex rounded. Valva slightly upwardly oblique, ventral margin medially bulged; cucullus moderately narrow; valval lobe finger-shaped, distal margin lined with a few nodules with short bristles. Anterior extension of juxta straight, median plate broad; posterior lobe exceeding the base of uncus. Phallus slightly arched, parallel-sided, with one plate-shaped cornutus and a few indistinct small nodules.

Female genitalia. Papilla analis elongate, covered with short and long bristles. Apophysis posterioris 3.5 x as long as papilla analis and 1.9 x as long as apophysis anterioris, apophysis anterioris 1.35 x as long as segment 8. Segment 8 quadrate, lateral margin sclerotized by a narrow band, proximal margin convex, strongly sclerotized, medially broader, caudal margin indistinct, concave, lined with several bristles; ventral longitudinal sclerotization broad, ovoid. Antrum slightly shorter than segment 8, anteriorly tapered and more sclerotized. Ductus bursae membranous, as broad as antrum. Corpus bursae ovoid, very large, with one crescent-shaped signum bearing two narrow and long protuberances, and two smaller leaf-shaped posterior signa of different size.

Biology. Unknown. The specimens collected by the first author were netted from Salvia rosmarinus Spenn (Lamiaceae) in a pine forest.

Distribution. Tunisia.

Results. P. illucidella was synonymized with bicostella by Back (1973). Both morphology and genetics suggest it is a valid species (stat. rev.).

Figures

FIGURE 65. Neighbor-joining tree based on the barcoding fragment of the COI gene (p-distance model) of all available species of the Pleurota bicostella species group. “MM26262” etc. are BOLD sample IDs.

FIGURE 66. Distribution map of P. illucidella Chrétien, P. lepigrei Lucas and nine new species of the P. bicostella species group. Map based on Google Maps © 2021.

FIGURES 9–16. Adults and labels of Pleurota spp. 9–11. P. illucidella Chrétien. 9. ♀ holotype. 10. ♂. 11. ♀. 12–14. P. lepigrei Lucas. 12. ♂ holotype. 13. ♂. 14. ♂. 15. P. ericella (Duponchel), ♂. 16. P. phaeolepida sp. nov., ♂ holotype.

FIGURES 37–38. Male genitalia of Pleurota spp. 37. P. asiatica Back, holotype, Genitalpräparat Nr. 00597 H.-E. Back. 38. P. illucidella Chrétien, GP 6021 J. Tabell.

FIGURES 54–56. Female genitalia of Pleurota spp. 54. P. asiatica Back, paratype, Genitalpräparat Nr. 00605 H.-E. Back. 55. P. illucidella Chrétien, GP 5917 J. Tabell. 56. P. lepigrei Lucas, GP 5444 J. Tabell.