Amphinemura baumanni, Murányi, Dávid & Li, Weihai, 2013

Murányi, Dávid & Li, Weihai, 2013, Two new species of stoneflies (Plecoptera: Nemouridae) from Northeastern India, with a checklist of the family in the Indian Subcontinent, Zootaxa 3694 (2), pp. 167-177 : 168-169

Amphinemura baumanni sp. n.

( Figs. 1–4 )

Diagnosis. Male paraproct: outer lobe divided into a comb-like inner branch and a double-curved outer branch terminating in a large spike; median lobe shield-like, covering most of the basal half of outer lobe. Male epiproct: elongated, with a backward directed apical horn; ventral sclerite with undulated ventral edge, bears a row of short spikes along its apical two thirds.

Type material. Holotype male: INDIA: West Bengal State, Darjeeling District, Ghum, Senchal Reserve Forest, 2200 m a.s.l., 19.04.1967, leg. Gy. Topál (HNHM: PLO4; terminalia cleared in KOH and kept in the same vial); Paratypes: same locality and data: 2 males (HNHM: PLO5), 1 male (HIST), 1 male (BYU).

Description. Small species, macropterous. Forewing length: holotype 6.5 mm, paratypes 6.5–7.0 mm. Head brown, details shaded by desiccation, antenna probably lighter. Pronotum brown, trapezoid, slightly longer than wide; surface rough with distinct rugosities. Legs pale; wings hyaline, venation pale. Abdomen pale except for terminal segments, which are brown. Pilosity short and indistinct.

Male terminalia ( Figs. 1–4 ): Hypoproct two times longer than wide, almond-shaped, apical part gradually tapering and blunt; vesicle very slender, four times longer than wide. Paraproct inner lobe simple, much shorter than median lobe, apex blunt. Median lobe connected to the inner lobe with a well sclerotized basal ridge, large and shield-like, covering most of the basal half of the outer lobe; inner edge bears a small, pointed apex, otherwise the lobe lacks any spines or modifications. Outer lobe rather complex, well sclerotized and dark; basal half visible by transparency through the median lobe, curving outwards and divided about at the level of the apex of inner lobe. Inner branch of the outer lobe curving inwards then upwards, its blunt apex bears five to six large spikes, directed outwards and backwards; the spikes are blunt and the branch has a comb-like appearance. Outer branch of the outer lobe apically directed, then curved outwards while its apex curves inwards and rearwards; apex paler than the rest of the branch, bears a single, large and pointed straight spike. Cerci simple, rounded, base free of the paraproct base; terminal wart inconspicuous. Tergite IX weakly sclerotized but with two pocket-like indentations medially and a medially interrupted apical row of strong hairs. Tergite X with a rounded light area medially, beneath the apex of epiproct; a few short spikes surrond the area and the widened apical lobe is armed with two conspicuous ridges, directed inwards from base of the lobe. Epiproct strong and elongated with an apical horn. Dorsal sclerite forked after a short base, branches run laterally and slightly bent upwards, narrow, and delimit a large, membranous dorsal area; epiproct tongue-shaped in dorsal view. Ventral sclerite narrow, connected with the basal sclerites; its ventral edge is undulated in lateral view and bears a row of short spikes along its apical two thirds. The apical horn of the epiproct arises from a crescent-shaped median sclerite that is weakly connected to the ventral sclerite; the horn is directed backwards, dark coloured but with white tip.

Female: Unknown.

Affinities: Amphinemura baumanni is a member of the luteipes species group. The peculiar outer lobe of the paraproct distinguishes it from all other species of the group, being divided into a comb-like inner branch and a double-curved outer branch terminating in a large spike. Only A. elegans Zwick, 1980 (in Zwick & Sivec 1980) has a similar structure but that species distinctly differs in both the median lobe of the paraproct and in the epiproctal structures. With the exception of A. pseudoluteipes Aubert, 1967 and A. bomdilai Aubert, 1967 , Himalayan species of the group bear spikes only on the apical third of the ventral sclerite of the epiproct. The epiproct of the new species resembles that of A. bomdilai ; however, their paraprocts are distinctive.

Distribution and ecology. The species was collected half a century ago in a forest reserve at the northernmost edge of West Bengal, close to the border of Sikkim and Nepal ( Fig. 9 ). This area is part of the southern slopes of the Himalayas. The specimens were beaten from vegetation and the only other stonefly collected at the same time was a female of Peltopteryx zwicki Stark, 1989 (new record for West Bengal State).

Etymology. The species is dedicated to Prof. Richard W. Baumann, Provo, Utah, USA, in recognition of his work on the genus Amphinemura and the whole family Nemouridae . The name is used as the genitive of a noun of male gender.

Figures

FIGURE 9. Type localities of Amphinemura baumanni sp. n. (dot) and Sphaeronemoura siveci sp. n. (ring) — grey areas are above 1000 m, Indian states of published Nemouridae records marked with numbers as follows: 1 — Jammu and Kashmir; 2 — Himachal Pradesh; 3 — Tamil Nadu; 4 — West Bengal; 5 — Meghalaya; 6 — Assam; 7 — Arunachal Pradesh; 8 — Manipur; 9 — Mizoram.

FIGURES 1 – 4. Male terminalia of Amphinemura baumanni sp. n.; holotype, India, West Bengal, Ghum — 1: dorsal view; 2: laterodorsal view; 3: ventral view; 4: lateral view — scale 0.5 mm.