Chytonix Grote, 1874

Choi, Sei-Woong, Heo, Un-Hong & Kim, Sung-Soo, 2021, Four species of Noctuoidea (Lepidoptera), new to Korea, Zootaxa 4999 (6), pp. 582-590 : 583-585

Genus Chytonix Grote, 1874

Type species: Apamea iaspis Guenée

1 * Chytonix brunneofascia Choi and Heo , sp. nov.

( Figs. 1A , 2A, 2B , 3A, 3B )

Type material. Holotype: male, Korea, Gwangju, Donggu, Valley Yongchu, 24 May 2018 (larva), 15. June 2018 (eclosion), Un-Hong Heo ( MNU), genital slide no. MNU 1149 ; Paratypes: 2 males, with the same data as holotype. Un-Hong Heo ( MNU, NIBR), genital slide no. MNU 1166 .

Diagnosis. This species is reminiscent of rather certain Eustrotiinae or Bryophilinae species than other members of the genus Chytonix . It can be distinguished easily from the northeasterly distributed congeners occurring in Japan, NE China, Korea, and Taiwan by the dark brown and broad median suffusion of forewing that meets with the outer margin below termen, the large but rather slender, medially constricted elliptical reniform stigma, and the dark brownish hindwing. The male genitalia conforms to the genus Chytonix and is characterized by long, tapered uncus, simple membranous transtilla and juxta, long and slender valva with basally strongly sclerotized costa with a sharply pointed process and basally fused sacculus with two seed-shaped processes, and a long tubular aedeagus with many spiniform cornuti in the vesica. The new species differs from C. albonotata (Staudinger, 1892) mostly by the large hook-shaped costal process of the valva.

Description. Wingspan 20 mm. Antennae filiform in male; frons dark brown; labial palpi long, twice to eye diameter, porrect, 2 nd segment long, thick. Body grayish, legs dark brown with yellowish-white tibial joints. Forewing dark brown in ground color; basal part tinged strongly with dark ochreous-brown on dorsum; median fascia costally broad, tapered towards dorsum below the cell, reniform stigma large, elliptical, medially somewhat constricted, outlined with blackish and filled with fumous gray; antemedial line blackish, strongly oblique; upper part of postmedial line obsolescent, lower section sharply defined by dark brown and by whitish at tornus; subterminal line oblique below termen angled towards outer margin at cubital veins; dark median submarginal suffusion expanded from antemedial line to outer margin at medial veins, its outer margin concavely curved backward at cubital veins and follows postmedial line towards dorsum; the outer part of the marginal area with fine whitish-gray irroration; tornal patch conspicuous, large ochreous brown. Hindwing pattern-less, dark brown. Abdomen blackish.

Male genitalia. Uncus long, tapered, distally hooked; tegumen relatively short and broad, penicular lobes rounded, densely hairy; transtilla simple, membranous; juxta simple, small, more or less cordiform with truncated ventral apex; saccus long, V-shaped. Valva long, slender; cucullus elongated and apically finely rounded, densely setose with fine bristles; corona reduced; costa medially slightly humped; erect part of harpe (clasper) strongly sclerotized, rather falciform and apically sharply pointed; sacculus short; clavi relatively small, sclerotized, more or less seed-shaped processes. Aedeagus medium-long, cylindrical; vesica as long as aedeagus, everted forward, with large frontal diverticulum and with a more or less complete ring of numerous spiniform cornuti of various size along basal edge of diverticulum; ductus ejaculatorius originates at the base of the diverticulum and bent ventrad.

Larvae Body length 22 mm. Head light brown; body dark brown, mottled with whitish dots, parallel creamy white lines along the dorsum, laterally with a thick creamy white line.

Distribution. Korea.

DNA barcodes. One specimen of Chytonix brunneofascia from Gwangju was barcoded (Genbank accession number MW485584 ). The pairwise difference with Chytonix diehli Behounek (2002) (Genbank accession number KC819687 ) was 7.61%.

Etymology. The species name was derived from the shape of the central fascia of the forewing: brunneus, brown and fascia, band.

Remarks. Chytonix brunneofasciata feeds on Rhamnella franguloides (Maxim.) Weberbauer (Rhamnaceae) . In Korea, only one species of Chytonix was known: C. albonotata (Staudinger, 1892) . The clasping apparatus in the examined specimen is unfortunately incompletely opened, therefore the characters of certain parts (uncus, basal section of valva, harpe/clasper, etc.) are not really visible. A fully opened genital capsule would clearly show the real size and shape of uncus, the origin and structure of the harpe/clasper, and the clavi which are the most important specific features within the genus, besides the configuration of the vesica.

Figures

FIGURE 1. Adults of four species of Noctuoidea in Korea. A, Chytonix brunneofascia sp. nov., Holotype; B, Gynaephora atrata sp. nov. Holotype; C. Utetheisa pulchelloides; D. Pilipectus prunifera. Scale bar = 5mm.

FIGURE 2. Male and female genitalia of four species in Korea. A, B, Chytonix brunneofascia sp. nov.; C, D, Gynaephora atrata sp. nov.; E, F, G. Pilipectus prunifera; H, Utetheisa pulchelloides. Scale bar = 1mm.

FIGURE 3. Larvae of two species in Korea.A, B, Chytonix brunneofascia sp. nov.; C, Gynaephora atrata sp. nov.