(Figs. 58-61)

Peltoperla concolor Banks, 1931:411.

Lectotype ♂, Mt. Kinabalu, Sabah, East Malaysia (Museum of Comparative Zoology), designation

Hitchcock, 1962:83 Peltoperlopsis concolor: Illies, 1966:24

Peltoperlopsis concolor: Stark, 1989:521

Material examined. Malaysia: Sabah: Kinabalu Park Headquarters, 1560 m, 6° 00’ 22” N, 116° 32’ 34” E, 9- 18 April 1999, I. Sivec, 1 ♂, 1 ♀ (PMSL). Kinabalu National Park, Livagu River, 1410 m, 13 April 1999, I. Sivec, 1 ♀ (PMSL). Kinabalu National Park, Poring hot spring, 600 m, Sungai Kipungit, 23 April 1999, I. Sivec, 8 larvae (PMSL). Kundssang, Ranau, Negeri, 1800 m, 9 April 1994, S.C. Kang, 1 ♂, 1 ♀, 10 larvae (PMSL).

Remarks. Hitchcock (1962) redescribed the external genitalia of the male lectotype, and Stark (1989) provided figures of the female genitalia, eggs and armature of the ventrolateral aedeagal lobe. In order to enhance recognition of this species we are providing the following description of the male aedeagus and larva.

Male aedeagus. Asymmetrically lobed; sinistral lobe apically trifurcate and sparsely armed along ventroapical margin with short, setal-like spines; sinistral lobe trifurcate in ventral aspect; mesal part of lobe armed with large triangular and cultriform spines; microtrichia cover aedeagal base and apical part of sinistral lobe in ventral aspect (Figs. 58-59).

Larva. Pre-emergent body length 8.5-10 mm. General color pale brown to red brown without conspicuous pattern. Long, slender gills project from beneath prosternal and mesosternal plates and similar supracoxal gills occur on mesothorax and metathorax under wingpads; gills on paraprocts slender, delicate and upturned, median gill on ventroapical margin of tergum 10 apparently absent. Metasternum concave on posterior margin and completely fringed with small clavate setae (Fig. 60); lateral margins with slightly longer setae around base of coxae continuing onto sternal surface as a short row adjacent to lateral notch; mesosternum concave on posterior margin and fringed for a short distance with small clavate setae, but incomplete mesally; lateral margin fringe similar to metasternal fringe; prosternum with complete anterior fringe of close-set clavate setae but only a few bristles occur on posterior margin near sternal angles. Abdominal terga without intercalary bristles; posterior fringe rows comprised of medium length, widely spaced acute bristles with ca. 4-6 short clavate setae interspersed between larger bristles. Cerci long and slender; venter of segments from about segment 10 through about segment 23 bears one or two large, flattened, acute blade setae; basal and apical segments without blade setae; longest ventral setae about as long as segment; dorsum of segments with only short bristles (Fig. 61). Galea with prominent apical brush, lacinia tridentate.