Styloperla jiangxiensis Yang & Yang

Stark, Bill P. & Sivec, Ignac, 2007, A Synopsis Of Styloperlidae (Insecta, Plecoptera) With Description Of Cerconychia Sapa, A New Stonefly From Vietnam, Illiesia 3 (2), pp. 10-16 : 13-15

Styloperla jiangxiensis Yang & Yang ( Figs. 10 ‐ 13 )

Styloperla jiangxiensis Yang & Yang, 1990 . Acta Agriculturae Universitatis Jiangxiensis 2:45 ‐ 46.

Material examined. China: Zhejiang, Long Wang Shan , 560 m, 30° 28 ʹ N, 119° 22 ʹ E, 3 June 1999, I. Sivec, 4 ♂, 3 ♀ ( PMSL). Zhejiang, Long Wang Shan , 600 m, 30° 28 ʹ N, 119° 22 ʹ E, 3 June 1999, I. Sivec, 2 ♂, 1 ♀, 2 exuviae ( PMSL). Zhejiang, Long Wang Shan, 700 ‐ 1000 m, 30° 28 ʹ N, 119° 22 ʹ E, 4 June 1999, I. Sivec, 3 ♂, 1 ♀ ( PMSL).

Adult habitus. Biocellate. General color pale yellow brown. Head pale over much of occiput but stem of epicranial suture dark brown and areas adjacent dusky brown. Dark brown ocellar patch extends to narrow pale M ‐ line and forward of M ‐ line to anterior margins of frons. Pronotum completely margined with an impressed narrow black line and shadowed with dusky brown external to line; median pronotal band brown, disk with irregular brown midlateral band and paler rugosities in the anterolateral and posterolateral quadrants. Legs and antennae dark brown. Wings transparent, veins brown.

Male. Forewing length 12.5 ‐ 14 mm. Basal cercal segment swollen and armed near the apical margin with a prominent multispined spur ( Figs. 12 ‐ 13 ) and a long curved process along the inner cercal margin ( Fig. 10 ); process terminating with a pair of small spines and a pair of ventral, subapical spines ( Fig. 11 ). Cercal segments 2 ‐ 4 bear small clusters of mid dorsal spines and long setae ( Fig. 12 ). Aedeagus tongue shaped with a pair of dorsal sclerites bearing irregular striae; venter primarily membranous but with a slender pair of sclerotized bars which connect to the dorsal sclerites and extend from near midlength to the apex. Apex partially sclerotized and split; each apical flap armed with several rows of minute spines; apex somewhat foot shaped in lateral aspect.

2.

Female. Forewing length 16.5 ‐ 18 mm. Subgenital plate slightly produced into a small mesal tab; vaginal sclerites conspicuous through wall of sternum 8. Sternum 9 bearing weakly sclerotized lateral bars and a membranous mesal area armed with short setae; intersegmental membrane of sterna 9 ‐ 10 bearing a patch of microtrichia.

Egg. Typical of genus. Ovoid with collar absent and chorion smooth.

Remarks. Yang & Yang (1990) described this species from a single male taken at Jing Gang Shan in Jiangxi near the border with Zhejiang Province. Although the basal cercal spur is shown as somewhat longer in the figure prepared by Yang & Yang (1990) than for our specimens, we are tentatively placing these specimens as S. jiangxiensis on the basis of a similar color pattern, similarly armed apex of the cercal process, similarly shaped aedeagus, and proximity of collection localities. Unfortunately, without access to the holotype we are unable to confirm this placement.

The collection made at 600 m on Long Wang Shan includes two exuviae which are similar in size, coloration and body form to the Cerconychia livida nymphs described by Uchida & Isobe (1989). However these exuviae have bidentate, carnivorous type laciniae, paraglossae larger than glossae, a much reduced, chloroperlid ‐ like, apical maxillary palpal segment, and spurs rather than trifurcate setae on the tibial apex. The mandibles have four major teeth, a distinct mola, and a ventral row of peg bristles originating near the base of the second tooth and extending almost to the inner margin of the mandible. The mixture of chloroperlid ‐ styloperlid features suggests caution should be used in associating these exuviae with the adult Styloperla specimens collected with them.

Figures

Figs. 10‐13. Styloperla jiangxiensis SEM photomicrographs. 10. Male right cercus, dorsobasal aspect, 11. Apex of male cercal process, dorsal, 12. Male cercal spur and segments 2‐4, 13. Male cercal spur and spine of segment