Rivula guidiana, Jin & Han, 2025

Jin, Yuan Yuan & Han, Hui Lin, 2025, Descriptions of three new species of Rivula Guenée [1845] 1844 (Lepidoptera, Erebidae, Rivulinae) from China, with the checklist of Chinese species, Zootaxa 5583 (3), pp. 579-588 : 585-587

Rivula guidiana sp. nov.

(Chinese name: 桂dz涓njď)

urn:lsid:zoobank.org:act:4CACF4E3-FC70-42AC-B48C-A9A083F9CBD0

Figures 7, 8, 16

Type material. Holotype. male, China, Aut. Reg. Guangxi, Laibin City, Jinxiu County, Shuidi Village , 7–10 Jul. 2020, leg. K.L Wu, genit. prep. JYY-187-1, coll. NEFU . Paratypes. 2 males, China, Prov. Yunnan, Puer City, Jiangcheng, 15–17 Aug. 2008, leg. HL. Han, genit. prep. JYY-188-1, JYY-189-1, coll. NEFU .

Diagnosis. The new species is similar to R. curvifera in morphological characters (Figs. 9, 17), but it differs in the following characters (characters for R. curvifera are in parentheses):

Adult R. guidiana sp. nov. (Figs. 7, 8), the terminal area with a slender and long bar (a broad and short bar in curvifera ); antemedial and median lines absent at costal margin (distinct in curvifera ); terminal line region mixed pale ( curvifera without terminal line); the subcostal margin bar nearly extends to apex ( curvifera extends to apex).

In male genitalia of R. guidiana sp. nov. (Fig. 16), valva more paralleled by dorsal and ventral margin, and straight ( curvifera upcurved); cucullus straight (cucullus rounded); sacculus with expansion at 1/3 (rather smooth in curvifera ). Aedeagus of uniform thickness, tube-shaped, strongly sclerotized (slightly sclerotized and cone-shaped in curvifera ); carinal plate sclerotized, without spines (absent in curvifera ); vesica with 1 cornuti field on subbasal diverticulum, and densely covered small grains on median diverticulum ( curvifera with 2 cornuti fields on subbasal and median diverticula, grains absent).

Description. Adult (Figs. 7, 8). Wingspan 15–16 mm. Head gray-brown; labial palpi yellowish-brown, upcurved and extended forward but not beyond the frontal tuft; antennae yellowish-brown and filiform. Thorax darker brown; patagium and tegula lighter. Abdomen brown-yellowish with yellowish scales. Forewing light gray-brown, costal margin brown; basal, antemedial and median lines more indistinct; postmedial line only distinct in costal margin area, and pale; subterminal line pale, incurved to median line, and forming a large spoon-shaped mark; the subcostal margin bar broad, pale, and extending to nearly the apex, with spoon-shaped mark forming a slender, long bar shape at cell terminal part; terminal line region pale, gradually widening from costal to inner margin. Hindwing lighter than forewing; the fringe grayer at inner margin; discal spot absent.

Male genitalia (Fig. 16). Uncus strongly sclerotized, hook-shaped, base wide and with a triangular opening, approximately of equal length to the tegument. Tegumen narrow and strongly sclerotized, same length as uncus. Vinculum narrow, broad V-shaped and strongly sclerotized. Saccus funnel-shaped. Juxta hill-shaped, with ear lobe on both sides. Valva more membranous, chair-shaped; cucullus straight; costa broader and longer than sacculus, and forming a small and narrow gap at basal part; sacculus bent at an obtuse angle at 1/3; clasper short and very small mastoid-shaped.Aedeagus tube-shaped, strongly sclerotized; carinal plate sclerotized, without spines; ceacum 1/3 times longer than aedeagus. Vesica membranous, with 1 subbasal diverticulum; and 6 median diverticula, 4th and 5th median diverticula densely covered with small grains; the subbasal diverticulum covered with a strongly sclerotized cornuti bar.

Female genitalia. Unknown.

Bionomics. The species was collected between June to August at altitudes ranging from 800 to 1200m. The collection site was located near a subtropical evergreen broadleaf forest with a plentiful number of shrubs (Fig. 22).

Distribution. China (Guangxi; Yunnan).

Etymology. This species name is a combination of two Chinese words, which refers to Aut. Reg. Guangxi (“Gui” for short in Chinese) and Yunnan Province (“Dian”). The name indicates the two provinces: Guangxi and Yunnan.