Anacroneuria wokomung, Stark, 2012

Stark, Bill P., 2012, Anacroneuria Pakaraima And A. Wokomung, Two New Stonefly Species From Guyana (Plecoptera: Perlidae), Illiesia 8 (10), pp. 114-118 : 117

Anacroneuria wokomung sp. n.

( Figs. 6-13 )

Material examined. Holotype ♂ and 2♀ paratypes from Guyana, District 8 , Mount Wokomung, 736 m, 05 ° 07’ 43.2” N, 59 ° 48’ 40.0” W, Malaise trap, 21-26 October 2004, ROM 2004531 , B. Hubley ( ROM). Additional paratypes (pinned). Guyana: District 8, Mount Wokomung, 1411 m, 05 ° 05’ 33.4” N, 59 ° 50’ 34.5” W, Mercury vapor light, 2-8 November 2004, ROM 2004521 , B. Hubley 4♂, 1♀ ( ROM).

Adult habitus. General appearance in alcohol pale white with limited brown pigment pattern. Head entirely pale except for pale brown antennae ( Fig. 6 ); pronotum pale over most of disk, but with narrow, dark brown pigment bands near lateral margins. Legs pale except for narrow dark bands at distal ends of tibiae and femora. Wings pale along costal margins including subcosta and radius, but with pale amber pigment forming a longitudinal band over bases of anal veins, extending across cubito-median veins to apical margin ( Fig. 7 ). A circular unpigmented area is located distal to cord crossveins; the first cubital vein and cord crossveins are dark brown.

Male. Forewing length 10.5-11 mm. Hammer strongly sclerotized with parallel lateral margins; height about equal to width ( Fig. 8 ). Aedeagal apex broadly rounded in lateral aspect ( Fig. 10 ), bearing a short recurved, ventroapical tip ( Fig. 9 ), and a short, thick dorsal keel line ( Fig. 11 ). Ventral membranous lobes absent, but basolateral area of aedeagal apex bulging slightly. Aedeagal hooks slender.

Female. Forewing length 13-14 mm. Subgenital plate 4-lobed ( Fig. 13 ). Inner lobes separated by a shallow, median notch, but notch separating outer lobes acute. Mesal sclerite of sternum 9 bearing a basomedian patch of fine short setae and patches of more prominent setae extending to posterior margin of segment. Posterior sclerite poorly developed. Intersegmental membrane armed with fine microtrichia.

Egg. Outline spindle shaped, typical of genus ( Fig. 12 ).

Larva. Unknown.

Etymology. The species name, used as a noun in apposition, is based on the type locality.

Diagnosis. Because the wing pigment pattern is similar, this species is identified as A. paria Stark, 1999 in the key proposed by Stark (1999) for Anacroneuria known for northeastern South America. However, the ventroapical region of the aedeagus in that species appears trilobed (see Fig. 34 in Stark 1999), the hammer is a short, thimble-shaped structure (see Fig. 33 in Stark 1999) and the female subgenital plate bears a moderately deep median notch (see Fig. 54 in Stark 1999). The male and female reproductive structures for A. wokomung are not similar to other regional species ( Stark 1999; 2000). The following key to males of Guyana Anacroneuria is presented to aid in recognition of the two new species. Figure numbers referenced in the key refer to Stark (1995, 1999; 2000), or to those presented in this study.

Figures

Figs. 6-13. Anacroneuria wokomung structures. 6. Head and pronotum. 7. Forewing. 8. Male sternum 9. 9. Male aedeagus, ventral. 10. Male aedeagus, lateral. 11. Male aedeagus, dorsal. 12. Egg outline. 13. Female abdominal sterna 8-9.