Leichosila Schmidt 2009, gen. n.
Creators: name: Schmidt, Christian
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Erebidae
Leichosila

description: <i>Leichosila</i> Schmidt, gen. n. urn:lsid:zoobank.org:act: 37F4D9EA-EDF5-4376-B9D3-D41901CBB5A7 <b>Type species.</b> <i>Leichosila talamanca</i> Schmidt, sp. n. <b>Diagnosis.</b> <i>Leichosila</i> can easily be distinguished externally from all other New World arctiines by the unique wing pattern and colour, consisting of a grey to whitish- grey ground colour with a pattern of dark grey-black, incomplete forewing bands that are ochre yellow centrally (Figs 1, 2). Structurally, the following combination of characters is unique: male antennae simple (Fig. 9), juxta very broad and shallow (5 × wider than long; Fig. 8); male valve lacking medioventral lobe (Figs. 3a, 4a), abdominal markings absent (Figs. 1, 2). Th e juxta shape is a putative autapomorphy of the genus and is unlike that of any other New World spilosomine. <b>Description.</b> Male (female unknown). <b>Head <i>–</i></b> Male antenna filiform in dorsoventral view, ciliate and subserrate ventrally; segment slightly longer than wide (Fig. 9); dorsal antennal scales greyish brown; palpi porrect, 3 rd segment ½ length of 2 nd segment; vestiture of palpi, frons and vertex dusty brown grey; haustellum reduced and poorly sclerotized, presumably non-functional. <b>Thorax <i>–</i></b> Vestiture of vertex and ventrum of thorax, patagia, tegulae and legs dusty brown grey and shaggy; apex of prothoracic tibia with two subequal, blunt, triangular projections; two meso- and metathoracic tibial spurs, the posterior spur slightly longer than anterior, length of spurs approximately equal to tibial width at apex; metepisternum with rounded ridge along anterior margin, microtymbals absent. <b>Forewing</b> (Figs. 1, 2) <i>–</i> length 13.4 to 16.1 mm; ground colour dark mouse grey to whitish grey; 5 transverse bands of yellowish ochre, outlined in dark charcoal grey; bands evident as five discrete cells along costa, three basal bands obsolete in medio-basal area, and again present along anal margin except for basal-most band; ochre and grey areas of three distal bands confluent in costal half, with ochre scaling extending along veins; distal band often darkest and most complete; pattern similar ventrally, but colours washed-out. <b>Hindwing</b> (Figs. 1, 2) – ground colour dusty grey to whitish grey, with irregular dark-grey subterminal spots and medial spot, these varying in contrast from pronounced to obsolete against darker ground colour; pattern similar ventrally, but colours of subterminal spots washed-out; medial spot darker ventrally than on dorsum, often extending to costa and basally along costal margin. <b>Abdomen</b> – vestiture dusty brown grey dorsally and ventrally; evenly coloured without distinguishable markings (Figs. 1, 2); coremata between 7 th and 8 th sternite absent (Fig. 5); 8 th sternite moderately sclerotized, trapezoidal, 2 × as wide as long (Fig. 5); lateral sclerites of 8 th sternite moderate sclerotized basally, mem- branous distally, equalling width of sternite in length (Fig. 5); 8 th tergite sclerotized, entire. <b>Male genitalia</b> – Uncus triangular to bottle-shaped in dorsal view, length 2 × that of basal width (Figs. 6, 7); basal half sparsely setose; apical third flattened laterally, down curved, resembling a bird’s beak in lateral view; apex truncate in caudal view; ventrally with membranous area extending halfway to apex (Figs. 6, 7); dorsal margin of tegumen recurved caudad, extending to base of uncus; valve consisting of a simple, sickle-shaped, slightly laterally flattened process (Figs. 3a, 4a) extending dorso-caudally as far as uncus apex (in natural position); valve devoid of processes and lobes (Fig. 3a), or with small sub-basal process on dorsal margin of costa (Fig. 4a); lateral process of transtilla consisting of a poorly delineated, sclerotized region contiguous with membranous area dorso-laterad of anellus, forming shallow, rounded pyramidal prominences directed dorsad; saccus broadly u-shaped, length equalling ¾ height of genital capsule; juxta u-shaped and slightly convex ventro-caudally, very broad and shallow, about 5 × broader than height at midline (Fig. 8); phallus unadorned and relatively stout, approximately 4 × as long as wide (Figs. 3b, 4b); coecum strongly curved ventrad by 90°; vesica globose with four basal diverticula (Fig. 4b), total diameter equalling length of phallus; two diverticula positioned basally and left-laterad, adjacent to each other; two additional diverticula positioned ventro-basally and also adjacent to each other; left half of vesica scobinate, grading to smaller spicules on right side; ductus ejaculatorius positioned right laterad. <b>Etymology.</b> The name is feminine in gender, and is derived from the Greek stem for lichen, <i>leichos</i>, and the Latin for yellow ochre, <i>silaceus</i>, reflecting the odd yellowochre colour of the forewing bands, very unusual for an arctiine. Th is colour pattern is presumably cryptic on lichen-covered trees. <b>Remarks</b>. Th e caudally recurved dorsal margin of the tegumen and lateral lobes of the 8 th sternite of <i>Leichosila</i> are unique autapomorphies of the Spilosomina (Schmidt 2007). The morphology of the male genitalia (valve prong-like and relatively simple, uncus broadly triangular) and wing shape/pattern place <i>Leichosila</i> near the <i>Hyphantria</i> Harris group of genera, consisting of <i>Hyphantria</i>, “ <i>Spilosoma ” (sensu lato)</i>, <i>Alexicles</i> Grote, <i>Estigmene</i> Hübner, and the “ <i>Hypercompe</i> ” <i>permaculata</i> (Packard) group, although I could find no synapomorphies to suggest a possible sister genus. The filiform antenna and absence of dorsal abdominal markings are rare among all spilosomines, but this condition occurs in some <i>Hypercompe</i> species and <i>Spilosoma vagans</i> (Boisduval), respectively. An incomplete ‘barcode’ fragment (319 base pairs) of the <i>cox1</i> mtDNA gene of a single <i>L</i>. <i>talamanca</i> specimen (Barcode of Life Data System; Ratnasingham and Hebert 2007) was approximately equally divergent from species of all <i>Hyphantria</i> -group genera by 5.6 % to 7 %. Th is level of divergence is congruent with the highly autapomorphic morphology of <i>Leichosila</i>, but unfortunately does not provide possible clues to generic relationships to the rest of the group. The <i>Hyphantria</i> group is restricted to Central and North America (except for <i>Estigmene albida</i> (Stretch) which occurs south to Colombia), but <i>Leichosila</i> is more closely allied to this group than to Neotropical <i>Paracles</i> Walker and Andean “ <i>Phragmatobia</i> ” to which <i>Leichosila</i> shows some superficial similarities but structurally it is quite different.
description: Published as part of <i>Schmidt, Christian, 2009, A new genus and two new species of arctiine tiger moth (Noctuidae, Arctiinae, Arctiini) from Costa Rica, pp. 89-96 in ZooKeys 9 (9)</i> on pages 90-92, DOI: 10.3897/zookeys.9.151, http://zenodo.org/record/576455
description: {"references": ["Schmidt BC (2007) Systematics of Grammia tiger moths (Lepidoptera: Noctuidae). Ph. D. thesis, Edmonton, Alberta: University of Alberta.", "Ratnasingham S, Hebert PDN (2007) BOLD: Th e Barcode of Life Data System. Molecular Ecology Notes 7: 355 - 364."]}