Vargasia Brown 2024, new genus

Vargasia Brown, new genus LSIDurn:lsid:zoobank.org:act: A620E17D-413A-4843-BF9A-E85A43DA84BE Type species: Vargasia karsholti Brown, new species. Diagnosis. Vargasia is similar to Transtilliana in forewing shape, length, and maculation, and in their shared elongate labial palpi. Superficially, Vargasia is easily recognized by the white to cream-colored scaling of the head, dorsum of the labial palpi, and dorsum of the thorax, with a contrasting brown base of the costa of the forewing. Morphologically, it is easily distinguished from all other euliine genera by the combination of the elongate-rectangular valvae with a truncate apex, the spined transtilla, and the evenly spaced row of cornuti in the vesica of the phallus. The exceptionally elongate labial palpi are shared with members of the Anopinella group of genera (i.e., Anopinella Powell, Seticosta Razowski, Strophotina Brown, and Punctapinella Brown), with which the genitalia have little in common. Vargasia shares with Accuminula Brown a spiny venter of the median process of the gnathos, a spiny dorsum of the transtilla, and relatively parallel-sided valvae However, the two genera are dissimilar in facies and in the female genitalia—females of Accuminulia are characterized by a series of strongly developed, longitudinal creases throughout the ductus bursae that are absent in Vargasia. Description. Head: Vertex rough-scaled, with scales directed anteriorly; scales of upper frons rough, scales of lower frons shorter, more appressed to surface of frons; antenna ca. 0.5 length of forewing, weakly serrate, with one row of scales per flagellomere, sensory setae ca. 0.3 times width of flagellomere in male, shorter and sparser in female; ocellus greatly reduced; chaetosemata well developed; labial palpus with scaling slightly expanded mesally on second segment, third segment long, exposed, combined length of all segments 3.5‒3.8 times diameter of compound eye. Thorax: Dorsum smooth-scaled, metathoracic tuft absent. Legs unmodified, without hairpencil or other male secondary scales. Forewing length ca. 2.4 times width; costa evenly arched throughout, male without costal fold; termen straight, oblique; all veins present and separate, chorda absent, M-stem present, R 4 to costa, R 5 to termen. Hindwing with all veins present and separate, Rs and M 1 connate to short-stalked; CuP weak at margin; frenulum with one bristle in male, three in female. Abdomen: Male genitalia (Fig. 23) with tegumen moderately rounded; vinculum elongate-ovate; uncus a narrow, curved rod, uniform in width throughout; socius elongate, crescent-shaped, pendant, densely clothed in long, fine setae; gnathos simple, arms joined disto-medially forming a triangular plate with fine teeth on venter; transtilla a broad, subrectangular plate densely covered with small spines; valva elongate, narrow, parallel-sided, truncate apically, sacculus ill-defined, a small triangular tooth from venter of valva ca. 0.6 distance from base; juxta a simple, broad, V-shaped plate; phallus ca. 1.2 times as long as valva, weakly bent in basal 0.3, phallobase with conspicuous thumb-like process ventrally at distal end, vesica with a row of 12 short, aciculate, non-deciduous cornuti. Female genitalia (Fig. 42) with papilla analis ca. 3 times as long as wide, rounded posteriorly, papillae joined posteriorly forming a U-shaped junction; apophyses slender, posteriores ca. 1.1 times length of anteriores; eighth tergum with broadly rounded anterior margin; sterigma a simple, broad, weakly sclerotized plate with a pair of spiny, elongate, inward-projecting lateral lobes; ductus bursae broad, ca. 3.5 times as long as wide, ca. 1.1 times length of corpus bursae, densely spinulose, without conspicuous antrum; corpus bursae round, finely spiculate throughout, with signum lacking. Distribution and biology. This monotypic genus is known primarily from Argentina, with a single record from Chile. The life history is unknown Etymology. The generic name is a patronym for my colleague Héctor Vargas, in honor of his numerous contributions to our knowledge of the microlepidoptera fauna of Chile.