Holotype male: China: Guangdong Province, Chebaling Nature Reserve, 114.1320E, 24.7128N, 17 June, 2009, leg. Hai-Yang Xue and Bo Yu. Paratypes: 4 males and 2 females, same data as holotype.

Distinguishing characteristics of this species include a slender aedeagal tube that has an upcurved, medial, finger-like, membranous lobe on the ventral surface, and a short, blunt, ventrally curved aedeagal sac with a dorsoapical patch of spines.

Adult habitus. General body color yellow patterned with brown. Head slightly wider than pronotum with a brown stigma on anterior frons and a subtriangular dark brown area covering ocelli; compound eyes dark and antennae brown (Figs 1, 9–10). Pronotum disc yellow with pale brown rugosities (Fig. 1). Wing membrane subhyaline, veins brown; legs yellow, femora grading to brown distally. Cerci pale (Figs 9–10).

Figure 1. 

Neoperla chebalinga sp. n. Male head and pronotum, dorsal view.

Male (Figs 1–5, 9). Forewing length 13.5–14.0 mm, hindwing length 11.5–12.0 mm (n = 5). The posterior margin of tergum 7 with a raised process densely covered with sensilla basiconica. Tergum 8 bears a recurved oval process with small spines at the distal margin (Figs 2–3). Tergum 9 without sensilla basiconica. Hemitergal processes of tergum 10 slightly curved anteriorly (Fig. 2). Aedeagal tube slender, strongly sclerotized dorsally, weakly sclerotized ventrally except for the basal bulb and an upcurved, ventromedial, finger-like membranous lobe. Aedeagal sac short and gradually tapered to a blunt apex, curved ventrally with a dorsoapical patch of spines (Figs 4–5).

Figures 2–3. 

Neoperla chebalinga sp. n. Male terminalia: 2 dorsal view 3 lateral view.

Figure 4–5. 

Neoperla chebalinga sp. n. Aedeagus: 4In situ, lateral view 5 Everted, lateral view.

Female (Figs 6–7, 10). Forewing length 15.5–16.0 mm, hindwing length 13.0–13.5 mm (n = 2). General color and pattern similar to males. Subgenital plate of sternum 8 slightly produced and lightly sclerotized posteromedially (Figs 6, 10). Vagina elongate-oval, lined sparsely along lateral margins. Spermathecal stalk short, spermatheca oval and curled at tip (Fig. 7).

Figure 6. 

Neoperla chebalinga sp. n. Female terminalia, ventral view.

Figure 7. 

Neoperla chebalinga, sp. n. Female genitalia, vagina and spermathecum, lateral view.

Eggs (Fig. 8). Outline oval. Collar short and surrounded by 1–2 irregular rows of follicle cell impressions. Primary striae join rim on sides of collar, narrow and widely spaced; each pair of primary striae enclose many secondary striae; sulci with dense pits. Lid small consisting of follicle cell impressions (Fig. 8).

Figure 8. 

Neoperla chebalinga sp. n. Egg, lateral view.

Figure 9–10. 

Neoperla chebalinga sp. n. Habitus: 9 Male habitus, dorsal view 10 Female habitus, dorsal view.

The species is named after the type locality, Chebaling Nature Reserve.

The new species is a member of the N. clymene group possessing a slender and mostly sclerotized aedeagal tube. The processes of terga 7–8 and aedeagus of the new species are similar to those of N. furcostyla Li & Qin, 2013 (in: Li et al. 2013b) and N. forcipata Yang & Yang, 1992 (Yang and Yang 1992). However, in N. furcostyla and N. forcipata, the aedeagal tube has a subapical fork instead of the medial finger-like lobe as in N. chebalinga. In addition, the aedeagal sacs of N. furcostyla and N. forcipata are not curved ventrally (see Figs 1–2 in: Li et al. 2013b and fig. 1 in Yang and Yang 1992).

1 male, 4 females, China: Guangdong Province, Chebaling Nature Reserve, 114.1320E, 24.7128N, 17 June, 2009, leg. Hai-Yang Xue and Bo Yu.

Female (Figs 11–13). Forewing length 12.0–12.5 mm, hindwing length 10.0–10.5 mm (n = 4). General color yellow to brown. Head nearly as wide as pronotum, with a subtriangular dark brown area covering ocelli; compound eyes dark and antennae pale brown. Pronotum disc yellow with pale brown rugosities. Wing membrane subhyaline, veins pale brown; legs yellow without darker markings. Cerci pale brown (Fig. 11). Subgenital plate of sternum 8 forming a small rounded sclerite with a posteromedial notch (Fig. 12). Vagina oval, lined densely around base of spermathecal stalk. Spermathecal stalk and spermatheca short, slender and curled at tip; a single accessory gland occurs near spermatheca tip (Fig. 13).

Figure 11. 

Neoperla mnong Stark. Female habitus, dorsal view.

Figure 12. 

Neoperla mnong Stark. Female terminalia, ventral view.

Figure 13. 

Neoperla mnong Stark. Female genitalia, vagina and spermathecum, lateral view.

China (Guangdong Province: Conghua County, Liuxi River; Shixing County, Chebaling Nature Reserve. Guangxi Province: Jinxiu suburb; Tianlin County, Pinglang). Vietnam (Di Linh, Dak Song, Gia Lai, Nghe An, Pleiku). Thailand (Chanthaburia).

This species is expected to be widespread in southern Asia. The male of N. mnong has been described from Vietnam by Stark (1987) and well-illustrated by Stark and Sivec (2008) from Vietnamese material. This species has been previously recorded from China by Du (1998) and Li et al. (2012b). Females of N. mnong from Vietnam were described as Javanita costalis by Navás (1932) and later described by Stark and Sivec (2008). In this study, females collected from Guangdong Province of China in 2009 are described and illustrated for the first time. The subgenital plate of these specimens is smaller and pigment patch over the ocelli is larger (for comparison see Figs 40, 43 in Stark and Sivec 2008).