Dargida radiata Dolibaina & Blas & Specht & Casagrande & Mielke 2020, comb. nov.
Creators: name: Dolibaina, Diego Rodrigo
name: Blas, German San
name: Specht, Alexandre
name: Casagrande, Mirna Martins
name: Mielke, Olaf Hermann Hendrik
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Noctuidae
Dargida
Dargida radiata

description: Dargida radiata (Köhler, 1966) comb. nov.
(Figs 1–4, 29, 34, 39, 43)
Lasiestra radiata Köhler, 1966: 109, fig. 2.6.— Poole 1989: 569.
Scriptania radiata (Köhler); Angulo & Olivares 1999: 24.
Diagnosis. Dargida radiata comb. nov. and D. roseilinea (Köhler, 1947) reinst. nom., comb. nov. are the only species of the genus with the forewing almost completely beige and veins covered by brown to reddish-pink scales. Dargida radiata is readily distinguished from D. roseilinea by the dorsal forewing whitish-beige ground color; vivid reddish-pink thick stripes restricted to veins; absence of reddish-pink stripes crossing discal cell; disco-cellular median (dcm) and inferior (dci) beige; and no spot in M 1 –M 2 near forewing discal cell. The male uncus of D. radiata is slightly shorter and distally broader than in D. roseilinea; the corona does not reach the cucullus ventral margin; and the third dorso-lateral diverticulum of the vesica bears thicker cornuti than in D. roseilinea. The female sterigma of D. radiata is broader than in D. roseilinea; the appendix bursae is longer; and lines of signa are well developed in D. radiata, whereas in D. roseilinea they are distinctively less developed.
Redescription. Head: uniformly whitish-beige; antennae filiform, dorsally white; labial palpi reaching the height of compound eyes, first segment short, second segment twice longer than first, third segment short and rounded; compound eyes hairy.
Thorax: uniformly whitish-beige including patagia, tegulae and legs; epiphysis as long as half of foretibia; midtibiae smooth, with a distal pair of spurs, outer spur half of the inner; metatibiae smooth, with two pairs of spurs, one at middle length and one distal, outer spur half of the inner.
Forewing: male 15.8–16.3 mm (n=6), female 16.8–17.7 mm (n=5); triangular, longer than wide; costal margin straight; apex not projected, rounded; outer margin slightly convex; tornus obtuse; anal margin slightly convex. Dorsal: ground color uniformly whitish-beige with vivid reddish-pink scales covering all veins except on end of discal cell, thicker on M 3, CuA 1 and CuA 2; fringe whitish-beige. Ventral: uniformly whitish-beige.
Hind wing: about 1.5 times longer than wide; costal margin about straight; apex obtuse; outer margin convex between apex and M 1, slightly concave in M 2 then convex; tornus rounded; anal margin slightly convex. Uniformly translucent white; fringe whitish-beige.
Abdomen: uniformly whitish-beige.
Male genitalia (Figs 29, 34): tegumen short, triangular, ventral arm of tegumen about half the length of valva, followed by a strong constriction leading to an expanded and setose peniculus. Dorsal arm of saccus shorter and narrower than ventral arm of tegumen. Saccus triangular, laterally spherical. Uncus cylindrical, slightly shorter than tegumen, anterior half upturned, smooth and curved, distal half flattened dorso-ventrally, as an elongated drop, gradually wider then tapering to a rounded end, straight and downturned, densely covered by setae both dorsally and ventrally. Subscaphium with two strongly sclerotized lateral bands on basal third, then fused in a ventral rectangular plate, slightly sclerotized. Transtilla strongly sclerotized, smooth, distal third tapering to a point, not fused together. Valva about six times as long as wide (at widest part), wider at the base then slightly narrower, dorsal margin strongly concave at the middle, ventral margin slightly convex, disto-ventral margin rounded, dorsal limit with cucullus with a shallow indentation; sacculus with meso-dorsal margin rounded and extending beyond base of costa and transtilla; costa uniformly narrow, dorsal margin strongly concave; costal process reduced, slightly sclerotized, not projected beyond apex of valva, fused with digitus; ampulla spear-shaped, smooth, perpendicular to valva, margins waved, 2/3 as long as cucullus, base wide tapering to a pointed end; clasper a small triangular projection at base of ampulla; digitus parallel to valva, shape and width similar to ampulla, but 1.3 times longer than ampulla and with straight margins; sensory plate as a small circular weak sclerotized area at the dorsal half near limit with remaining valva; cucullus 1/3 the length of valva, dorsal margin concave, ventral margin near straight, proximal half narrow, increasing in width distally, distal half spoon-shaped, width as at the mid length of valva, corona uniseriate, composed by mid-sized spine-like setae which do not reach the cucullus ventral margin, setae at the near ventral margin slightly shorter. Fultura inferior as an inverted club, base equilatero-shaped, as wide as uncus, followed by a uniformly narrow prolongation. Aedeagus thick, as long as valva, sinuous in lateral view, straight in dorsal view; opening of the ejaculatory bulb about half the aedeagus length; carina smooth, about 1/4 the aedeagus length, distal margin oblique in lateral view, dorsally with a short, pointed projection; ventral projection of aedeagus smooth, slightly sclerotized and shorter than carina; vesica tube like, slightly widened in the middle, smooth on basal third then minutely spiculated, with a dorso-lateral conic diverticulum near base, 1/4 as long as aedeagus, minutely spiculated on posterior half and smooth on anterior half, a second small ventral diverticulum, minutely spiculated, and a third dorso-lateral diverticulum, just posterior to the basal one and slightly bigger, bag-like, with a group of about 20 cornuti, 15 thick, remaining narrower, cornuti without sclerotized basal area.
Female genitalia (Fig. 39): papilla analis rhomboid, twice as high as long, posterior apophysis three times longer than papilla, narrow and straight, with a small expanded area near insertion to papilla. Tergum VIII rectangular, broader than papilla; anterior apophysis narrow, 3/4 as long as posterior apophysis. Sterigma rhomboid-shaped, slightly wider than long, tapered anteriorly and posteriorly. Bursa copulatrix about seven times the length of sterigma; ductus bursae sclerotized, as long as 1/2 bursa copulatrix length, posterior half narrow as the width at the anterior margin of sterigma, anterior half slightly swollen; appendix bursae raising ventrally, at the middle length of the bursa copulatrix, from ductus bursae anterior half, as long as corpus bursae length, coiled, turning 1 and 1/4 clockwise, distal 3/4 membranous, uniformly coated with minute spicules internally; corpus bursae uniformly spherical, as long as half the length of bursa copulatrix, internally coated with minute spicules arranged on longitudinal narrow bands, bearing four lines of signa, one dorsal, one ventral and one per side, each one with five aligned small plates as two fused circles with a short keel at the middle, internally serrated.
Etymology. Although not mentioned in the original description, the name probable refers to the color pattern of the dorsal forewing.
Distribution. Dargida radiata is distributed along the east margin of southern South America, from few sites of southern Brazil above 700 m of elevation, where the Araucaria Forest encounter the natural grasslands (states of Santa Catarina and Rio Grande do Sul), to the sea level in the province of Buenos Aires, Argentina (type locality) (Fig. 43).
Type material. The description of the species was based on the holotype, allotype and on an unknown number of paratypes, all from the type locality. The holotype male and allotype female of Dargida radiata are deposited at IFML and have the following labels: / HOLOTIPO / 18.2.[19]58 Vila Gessel Buenos Aires [Province, Argentina] / Ex Colección P. Koehler / Lasiestra radiata K DET KOEHLER // ALOTIPO / 12.2.[19]50, Villa Gessel Buenos Aires [Province, Argentina] / Ex Colección P. Koehler / Lasiestra radiata K DET KOEHLER /.
Additionally, a slide containing a male genitalia under the code 954 used for the illustration presented in the original description of L. radiata is deposited at the IFML and probably belongs to a paratype.
Analyzed material. ARGENTINA: Buenos Aires: Villa Gessel, 1♂ (holotype), 18.II.1958, Petrowsky leg. (IFML), 1♀ (allotype), 12.II.1950, Petrowsky leg. (IFML). BRAZIL: Rio Grande do Sul: Barracão, 1♂, 1♀, 1.II.2001, A. Specht leg. (MCTP 11220, 11221); São Francisco de Paula (Pró-Mata), 9♂, 6♀, 20.XII.2000, A. Specht leg. (MCTP 11174, 11176, 11179, 11180, 11181, 11182, 11183, 11184, 11187, 11173, 11175, 11177, 11178, 11185, 11186). Santa Catarina: Monte Castelo, 3♂, 4♀, 1.II.1993, V. Becker leg. (VOB 87032, USNM); Urubici (Serra do Panelão), 1300 m, 1♂, 14–17.III.2007, A. Moser leg. (CLAM).
Comments. Dargida radiata is a rare and poorly known species, despite being one of the most distinctive member of Dargida. Dargida radiata most similar species is D. roseilinea, as they are the only members in the genus to have a forewing almost completely beige with all longitudinal veins covered by brown to reddish-pink scales. The male and female genitalia of these species are only slight different suggesting that they are related closely. Dargida radiata is immediately distinguished from D. roseilinea by the absence of forewing intervenal brown to pale reddish-pink stripes, as well as the absence of a circular spot just after the end of the discal cell in M 1 –M 2. The forewing diagnostic characters of D. radiata are stable in the series of 27 specimens examined (15 males and 12 females), although the reddish-pink stripes of the forewing type’s series are slightly thinner than those from populations of southern Brazil. Furthermore, these species are likely allopatric, with D. radiata restricted to areas along the eastern portion of southern South America, either in low (Argentina) and mid elevations (southern Brazil), whereas D. roseilinea distribution is related to the Sierras Pampeanas of Argentina.
Köhler (1966) expressed doubt about the generic placement of L. radiata, stating a series of divergent morphological details in the male genitalia between this and the type species of Lasiestra Hampson. In fact, Lasiestra was erected to accommodate Neartic and Palaeartic species, and Poole (1989) considered the nine South American species originally assigned to this genus as Lasiestra “of authors”. At that time, however, the genus was already being considered a junior synonym of Lasionycta Aurivillius, but without counting on the South American taxa (Lafontaine et al. 1986; Crabo & Lafontaine 2009). Later, Angulo & Olivares (1999) transferred Lasiestra radiata along with Lasiestra plumbica Köhler to Scriptania Hampson based on genitalia characters. In the recent phylogenetic assessment of Scriptania, however, Rodríguez & Angulo (2008) removed the aforementioned species without mentioning their generic placement, thus returning them to their previous combinations, i.e., Lasionycta (= Lasiestra).
The combination of L. radiata with Dargida as proposed here and of L. castanea Köhler with Chabuata Walker (León et al. 2005), reduce to seven the South American species historically assigned to Lasiestra. Based on the general morphological aspects none of these species belongs to Dargida and their generic placement still needs to be determined.
description: Published as part of Dolibaina, Diego Rodrigo, Blas, German San, Specht, Alexandre, Casagrande, Mirna Martins & Mielke, Olaf Hermann Hendrik, 2020, Taxonomy of five neglected South American species of Dargida Walker (Lepidoptera: Noctuidae), pp. 199-217 in Zootaxa 4853 (2) on pages 200-202, DOI: 10.11646/zootaxa.4853.2.3, http://zenodo.org/record/4519085