Amphinemura meizhouensis, Mo & Wang & Yang & Li & Murányi, 2021

Mo, Raorao, Wang, Guoquan, Yang, Ding, Li, Weihai & Murányi, Dávid, 2021, Two new species and four unknown larvae of Amphinemurinae (Plecoptera, Nemouridae) from southern China, Zootaxa 5040 (1), pp. 77-101 : 83-86

Amphinemura meizhouensis sp. n.

( Figs. 5–7 )

Diagnosis. Male: terga IX–X with black spines, epiproct with a pair of outcurved lateral processes and a single longer median process, and with a pair of lateral bars having spinous and out-curved apex between lateral processes and median process. Paraproctal median lobe long and S-shaped with 3–4 apical spines; outer lobe slender and curved and with 1–2 apical spines. Female: pregenital plate large semicircular and pale, subgenital plate bicolored and rectangular, paragenital plates distinct and rectangular, inner genitalia with small sclerites.

Description. Adult habitus: Small sized species for the genus, general color brown. Head dark brown; antennae brown, basal portion paler; palpi light brown. Thorax brown; pronotum with distinct rugosities, rectangular with square corners. Legs light brown. Wing membranes semitransparent, veins brown. Abdomen brown with slightly darker terminalia.

Male. Forewing length 5.2–5.4 mm. Tergum IX weakly sclerotized, with 2 paramedial groups of black spinules and long hairs along mid-posterior margin ( Figs. 5C–D , 6B ). Sternum IX with long and narrow vesicle, apically slightly widened. Hypoproct rounded, apical half evenly tapering, apex unpigmented and nipple-like ( Figs. 5B, 5D , 6A ). Tergum X sclerotized, concavity beneath epiproct narrow with 2 spines along lateral sides. Cercus slightly sclerotized, stout and short. Epiproct twice longer than wide in dorsal view, distal portion with a pair of lateral process and a slender median process, but with a pair of sclerotized bars between them; in lateral view, the epiproct is slightly flattened with upcurved median process and downcurved lateral processes. The lateral processes strongly sclerotized, dark and horn-shaped, out-curved apex armed with several small spines; median process originates from ventral sclerite and slightly longer than lateral ones with unpigmented tip. Lateral bars on each side of midline, darkly sclerotized, with sparse small to bigger spines along its apical half; apex strongly outcurved nearly forming right-angled ( Figs. 5C–D , 6B–E ). Paraproct trilobed: inner lobe blunt triangular, well sclerotized; median lobe long, S-shaped in lateral view, apical portion up- and outcurved, apex weakly sclerotized with 3–4 spines; outer lobe curved, slender and thin but well sclerotized, caudally curved apex ends in 1–2 strong spines ( Figs. 5B–D , 6A–B, 6F ).

Female. Forewing length 6.1–6.4 mm. Sternum VII produced in a broad semicircular pregenital plate, covering anterior half of subgenital plate; the plate is pale, slightly bulging in lateral view, base of subgenital plate and inner genitalia transparent through its surface ( Figs. 10B–D ). Sternum VIII forms sclerotized, rectangular and bicolored subgenital plate, medial notch is being shallow by light median longitudinal wide stripe. Paragenital plate paired, forming small and rectangular brownish patches connected with posterolateral edge of subgenital plate through a membranous portion. Sternum IX trapezoidal, median half protruded anteriorly, in ventral aspect without anterior indentation. Paraproct short and brown, apex widely rounded; cerci short and brownish.

Female inner genitalia ( Fig. 6E ). Inner sclerite mostly membranous, mushhroom-shaped; lateral edges of subgenital plate turns around the sclerite dorsally; anteromedial portion with a short tubular structure, connected to the spermathecal ductus. The genital opening is wide and connected to the paragenital plates’ membranous portion.

Etymology. The new species is named after the type locality, Meizhou City.

Type material. Holotype male: CHINA: Guangdong, Meizhou City, Meixian Area, Yanyang Town , Changjiao Village , Yearning Tea Plantation Tourist Attraction , Longnashan Mountain Ecological Valley , Baoling Temple , 346.2 m, 24°22'34'' N, 116°22'4" E, 7 October 2019, Raorao Mo, Shuai Tang, Fengpin Qin et al. leg. ( HIST) . Paratypes: same date as holotype: 2 male and 4 female adults ( HIST) ; same data as holotype, Longnashan Mountain Ecological Valley , 325.0 m: 3 female adults ( HIST) .

Distribution and ecology. The new species was only found at Longnashan Mountains in Meizhou City of Guangdong, China and is also the first stonefly record from these mountains. Longnashan Mountains are adjacent to the Yinnashan Mountains. The new species was collected together with numerous Rhopalopsole sinensis Yang & Yang, 1993 . Currently, five known stonefly species were described from Meizhou City and they are all recorded in Yinnashan Mountains: Neoperlops gressitti Banks, 1939 , N. obscuripennis Banks, 1939 , Togoperla canilimbata ( Enderlein, 1909) (in: Banks 1939), Neoperla banksi ( Illies, 1966) (in: Banks 1939) and Kiotina chiangi ( Banks, 1939) . In Banks (1939), Yinnashan was written as Yim Na San. The latter pronunciation may come from Hakka dialect. Unfortunately, no associable larva of the new species was found.

Affinities. The new species should be placed in the A. sinensis group (sensu Li et al. 2018). It differs from other members of the group by the epiproct with additional lateral bars bearing spinous and an out-curved apex, and Sshaped paraproctal median lobe. Lateral bars or split median process of epiproct can be found in certain members of the group, A. ancistroidea Li & Yang, 2007 , A. divergens Stark & Sivec, 2010 , A. giay Stark & Sivec, 2010 , A. hamiornata Li & Yang, 2008 , and A. tianmushana Li & Yang, 2011 . But, the lateral bars of the new species can be easily separated from those species by the unique shape. The slight differences in the female subgenital plate are also typical of the known females of the sinensis group.

Figures

FIGURE 5. Amphinemura meizhouensis sp. n. (male). A. Head and pronotum, dorsal view. B. Terminalia, ventral view. C. Terminalia, dorsal view. D. Terminalia, lateral view. Scale bars: 0.2 mm.

FIGURE 6. Amphinemura meizhouensis sp. n. (male). A. Terminalia, ventral view. B. Terminalia, dorsal view. C. Epiproct, dorsal view. D. Epiproct, dorsal view. E. Epiproct, lateral view. F. Left paraproct, oblique lateral view. Scale bars: A–B=0.2 mm; C–F=0.1 mm.

FIGURE 7. Amphinemura meizhouensis sp. n. (female). A. Head and pronotum, dorsal view. B. Terminalia, ventral view. C. Terminalia after being cleared, ventral view. D. Terminalia, lateral view. E. Inner genitalia, dorsal view. Scale bars: 0.2 mm.

FIGURE 10. Amphinemura tulipa sp. n. (female). A. Terminalia, ventral view. B. Terminalia, lateral view. C. Inner genitalia, dorsal view. Scale bars: 0.5 mm.