Neoperla limushana, Mo & Wang & Li, 2021

Mo, Raorao, Wang, Guoquan & Li, Weihai, 2021, One new species and one poorly known species of Neoperla in the montivaga group (Plecoptera: Perlidae) from Hainan Province, China, Zootaxa 5004 (2), pp. 385-394 : 386

Neoperla limushana sp. nov.

( Figs. 1–5 )

Adult habitus ( Figs. 1a–1b , 3a ). Body color brown. Head pale, with a brown oval area interrupted by M-line and tentorial callosities, head pattern of specimens from Yinggeling paler and obscure; palpi pale brown; antennae generally brown, scape paler; biocellate, the distance between ocelli ca. 1.5X as wide as the diameter of the ocellus; interocellar area covered by a subtriangular dark brown spot; head slightly wider than pronotum. Pronotum pale brown and rectangular, median portion and scattered rugosities darker, with dark brown anterior and posterior margin; anterior corners sharp, while posterior corners rounded. Wings brownish and transparent, veins brown; legs brown; cerci light brown, apex darker.

Male ( Figs. 1–3 ). Forewing length 9.5–11.0 mm. Hindwing length 8.5–9.5 mm. Tergum 7 process a triangular lobe, apically covered with many sensilla basiconica. Tergum 8 medially covered with a subtriangular patch of sparse sensilla basiconica. Tergum 9 with mesal concave area bearing long hairs and with lateral sensilla basiconica patches on low swellings. Hemitergal processes of tergum10 up-curved, finger-like. Aedeagal tube with a pair of ventrolateral bands of triangular spines ( Figs. 2c–2e , 3c–3e ), but posterior portion of the aedeagal tube from Limu Mountain interrupted by a small area, which indicated by an arrow in Figs. 2c–2d; a spinous swelling located in ventrodistal area. The aedeagal sac curved ventrad, fully covered with tiny to large spines, lateral spines larger, with a blunt tip and a membranous transparent band ( Figs. 2c–2e ); aedeagal sac in paratypes from Yinggeling specimens with larger dorsomedial and posterolateral spines and a short erect tubular tip forming a right angle with the subapical sac ( Figs. 3c–3e ).

Female ( Figs. 4a–4b ). Forewing length 11.0– 12.5 mm. Hindwing length 9.5––11.2 mm. Habitus generally similar to male. Sternum 7 with a small distinct median sclerotized area. Subgenital plate of sternum 8 slightly produced, forming a short semicircular plate.

Egg ( Figs. 4c–4d , 5 ). Length 316–330 μm, width 157–170 μm (N=5). Plentiful mature eggs were dissected from female terminalia. Elongate oval in shape with 58–62 outer striae reaching collar and lid; striae set closely without sulci between them. Chorion brown. Hatching line inconspicuous. Micropyles sessile, dispersed between striae and placed in a ring closer to the opercular end. Collar short and distinctly flanged, with 2–3 rows of irregularly shaped follicle cell impressions (FCIs) towards collar rim; anchor not studied.

Type Material. Holotype: male ( HIST), China: Hainan Province, Qiongzhong County, Limu Mountain , 110 m, 19°29'N, 109°80'E, 2013.IV.3, Y.Y. Wang & Y.L. Jiang . Paratypes: 4 males, 3 females ( HIST) , 2 males, 2 females ( CAU) , same locality and date as holotype ; 2 males ( HIST) , 1 male ( CAU) , China: Hainan Province, Baisha County, Yinggeling, Nankai village , 308 m, 19°5'52.8" N, 109°24'57.24" E, 2015.IV.15, Y.Y. Wang & Y.L. Jiang .

Etymology. The new species is named after the type locality, Limu Mountain (Limushan in Chinese).

Distribution. China (Hainan Province). Limu Mountain is the longest mountain range in Hainan Province, and located in the southwest of the central part of the province. The mountain is full of waterfalls. Yinggeling is located in the west of the central part of Hainan Province. As the main part of Limuling mountain range, Yinggeling is the second highest peak in the province.

Remarks. Males of Neoperla limushana sp. nov. are unique in having aedeagal tube bearing a low spiny ventrodistal lobe, a pair of ventrolateral spiny bands; aedeagal sac is mostly covered by tiny spines and bears larger spines in lateral or dorsomedial and posterolateral area. But specimens from different places have slightly different in head pattern and spines arrangements of aedeagus. The molecular studies was delayed much and the data of the species was failed to obtain, possibly due to several years of commonly deposited condition. Further molecular studies are needed to confirm identity of these specimens.

The new species is a member of the N. montivaga group ( Zwick 1983) and shares similar external terminalia and aedeagus with N. fallax Klapálek, 1910 of the species group. However, they may be easily separated by details of aedeagal armature (compare figs. 16b–16d in Zwick 1983 and Figs. 2c–2e ). In N. fallax , aedeagal tube only has a dorsoapical band of tiny spines without swelling or more spinous patches; ventral surface of aedeagal sac armed with tiny spines, but the remaining surface fully covered by larger spines. Additionally, the shape of female subgenital plate and eggs of two species are different. In N. limushana , the female subgenital plate of sternum 8 is produced and semicircular posteriorly and eggs are elongate, while in N. fallax the subgenital plate is not produced posteriorly, only sometimes with a darker medial patch of sternum 8, and eggs are shorter, oval to nearly spherical.

Figures

FIGURE 1. Neoperla limushana sp. nov. (male). a. Adult habitus, dorsal view. b. Head and pronotum, dorsal view. c. Terminalia after being cleared, dorsal view.

FIGURE 2. Neoperla limushana sp. nov. (male). a. Terminalia after being cleared, lateral view. b. Terminalia after being cleared, oblique lateral view. c. Aedeagus, lateral view. d. Aedeagus, ventral view. e. Aedeagus, dorsal view.

FIGURE 3. Neoperla limushana sp. nov. (male from Yinggeling). a. Head and pronotum, dorsal view. b. Terminalia, oblique dorsal view. c. Aedeagus, lateral view. d. Aedeagus, ventral view. e. Aedeagus, dorsal view.

FIGURE 4. Neoperla limushana sp. nov. (female). a. Head and pronotum, dorsal view. b. Terminalia, ventral view. c. Eggs, lateral view. d. Entire egg, lateral view.

FIGURE 5. Neoperla limushana sp. nov. (eggs). a. Entire egg, lateral view. b. Lid, lateral view. c. Lid, apical view. d. Lid, apical view. e. Collar, lateral view. f. Collar, oblique apical view. (indicated by arrows).