Nemoura geei Wu 1929

Murányi, Dávid & Park, Sun Jae, 2011, Contribution To The Fall Stonefly (Plecoptera) Fauna Of Korea, Illiesia 7 (6), pp. 70-85 : 80-83

Nemoura geei Wu 1929

( Figs. 30-36 )

Nemoura geei Wu 1929 — Wu 1929:200. (original description of the male from China); Shimizu 1997:211. (redescription of male and female); Zhiltzova 2003:292. (monograph, with the original figures of N. brevicerca ); Teslenko & Zhiltzova 2009:150. (key, with the original figures of N. brevicercia ).

Nemoura pekinensis Claassen 1929 — Claassen 1929:511. (original description of the male and the female from China); Wu 1938:120. (syn. fide).

Nemoura brevicercia Zhiltzova 1982 — Zhiltzova 1982:37. (original description of the male from Russia); Shimizu 1997:211. (syn. fide).

Material examined. REPUBLIC OF KOREA: Gangwon Province, Inje-gun, Inje, 2km E of the city, tributary of Naerincheon River , 200m, N38°04.021’ E128°11.468’, 08.09.2010, leg. L á szló Forró, György Makranczy, D á vid Mur á nyi, Sun Jae Park , Jung Do Yoon : 3♂ ; Gangwon Province, Yangyang-gun, Seorak Mts., Hangae-ryeong Pass , 1.5km S of the rest area, brook in deciduous forest, 875m, N38°05.481’ E128°24.267’, 09.09.2010, leg. L á szló Forró, György Makranczy, D á vid Mur á nyi, Sun Jae Park, Jung Do Yoon : 3♂ 7♀ ; Gangwon Province, Inje-gun, Seorak Mts., Misi-ryeong Pass , beneath the rest area, brook in deciduous rocky forest, 745m, N38°12.963’ E128°26.189’, 10.09.2010, leg. D á vid Mur á nyi: 1♀ ; Gyeonggi Province, Gapyeong-gun, Hwaak Mts., Hwaak pass, 4.5km S of the tunnel, spring and its outlet, 280m, N37°57.376’ E127°31.718’, 11.09.2010, leg. L á szló Forró, György Makranczy, D á vid Mur á nyi, Sun Jae Park, Jung Do Yoon : 1♂ 4 larvae ; Jeollabuk Province, Muju-gun, Deokyu Mts., Baekryeon Temple , towards Osujagul Cave , sidebrook of Gucheondong Stream in deciduous forest, 985m, N35°51.069’ E127°46.169’, 14.09.2010, leg. Hye Woo Byeon, Tae Woo Kim, György Makranczy, D á vid Mur á nyi: 2 larvae ; Gyeongsangnam Province, Hadong-gun, Jiri Mts., Ssanggyesa Valley , parking lot beneath Daesung Camp , tributary of Hwagaecheon Stream in deciduous forest, 270m, N35°16.523’ E127°39.131’, 14.09.2010, leg. Hye Woo Byeon, L á szló Forró, Tae Woo Kim, György Makranczy, D á vid Mur á nyi: 1pharate ♂ 6 larvae (one matured male used for drawing Fig. 30 , one matured female used for SEMs Figs. 31-36 ) ; Jeollanam Province, Gurye-gun, Jiri Mts., Mt. Nogodan, at Nogodan shelter, brook in bamboo-mixed deciduous forest, 1350m, N35°17.740’ E127°31.574’, 15.09.2010, leg. Tae Woo Kim, D á vid Mur á nyi: 1♂ .

Mature larva ( Figs. 30-36 ). Body relatively slender, body length 6.0- 7.5 mm. General colour pale brown, with conspicuous dark brown pattern. Pilosity strong and distinct. Head stout, dark brown with black tentorial callosities and light brown patches on the occiput. Antenna light brown, but scape and pedicel dark brown. Pronotum subtrapezoidal, corners rounded, it is slightly narrowing towards the posterior margin; light brown with a few dark granules. Its length equals two thirds of its maximum width. Wing pads of typical length for macropterous species, meso- and metanotum dark brown with light patches and distinct, finger-like ornamentation. Legs typical of the genus, tibia as long as or slightly shorter than femur; width of hind femur two fifth of its length. Femora light brown with an apical dark brown ring, tibiae and tarsi light brown to brown. Abdomen relatively slender, integument light and matt. Ground colour light brown, but with three longitudinal dark brown patches on most of the segments; these are missing or small on terga I-II and VII-IX, and most intensive on terga V-VI. Tergite X entirely dark brown, mostly with a well delimited central patch. Ventral surface of the body light brown, with dark brown lines on the segment margins. Cercus light brown and long, with about 20 segments; segment sides nearly parallel, the width of segments 14-16 is one sixth of their length.

Pilosity: Head with dense, stout bristles and a few thin hairs; acute bristles occur only in the anterior third and around the compound eyes. Eye bear small setae between the ocelli. Antennal segments with short pilosity. Pronotum with short, stout bristles. Margin of the pronotum bearing stout, sharp bristles, the length of the longest ones is less than 1/10 of the pronotum’s width. The bristles on the anterior corners of the meso- and metanotum are longer than the marginal bristles of the pronotum. The setae placed in lines on the wing pads are short and blunt. Legs with dense setation. All femora bear both short and long, acute bristles and thin hairs. Long bristles occur on the apical half of the fore and mid femora, and on the apical two thirds of the hind femur. Bristles not in a regular arrangement; the longest ones reach half of the femur’s width on the first, one third on the hind legs. A bald median line is conspicuous on the dorsal surface of all femora and is covered with rounded scales. Apical row of short bristles present on all femora. Tarsi relatively stout, covered with thin hairs; apical spikes of tibiae short. Terga covered with short, acute bristles. Distal row with bristles of variable length; the longest ones on tergite V reach nearly half the segment’s length. Distal margin with very few tiny triangular spikes around the row of bristles. Cercal segments with a few thin hairs besides the apical whorl of bristles. The apical whorl on segments 14-16 is a set of short, clubbed bristles and 3-5 long, acute bristles mixed with thin hairs. Longest bristles reach two thirds of the segment’s length on segments 14-16.

Affinities. The larva can be easily distinguished from all known Far East Nemoura larvae on the basis of its distinctive dark brown and light brown pattern.

Geographical distribution and ecology. The species is known from Northeast China, the whole Korean Peninsula, the Russian Far East and Japan ( Shimizu 1997, Zwick 2010). Adults hitherto reported to occur from March to June ( Shimizu 1997, Zhiltzova 2003, Zwick 2010) and from September to October ( Shimizu 1997). In September we found both fully pigmented adults and immature larvae, suggesting a flight period even more extended towards autumn. Specimens were found at forest streams and springs, both with fast and slow flow and with stony, rocky or gravelly substrate mixed with sand. Nemoura geei proved to be the most frequent autumnal species of the smaller waterflows during our tour. Specimens were found associated with up to five species, but also the only stonefly collected at a particular habitat ( Table 1 ).

Figures

Fig. 30. Habitus of a mature larva of Nemoura geei Wu 1929, dorsal view (scale 1 mm).

Figs. 31-36. Larva of Nemoura geei Wu 1929. 31: pronotum; 32: fore femur; 33: hind femur; 34: 5th tergal segment; 35: basal segments of the cercus; 36: 15th segment of the cercus (scales 0.1 mm).