Perlesta browni Stark, 1989

Grubbs, Scott A. & Dewalt, R. Edward, 2018, Perlesta armitagei n. sp. (Plecoptera: Perlidae): More cryptic diversity in darkly pigmented Perlesta from the eastern Nearctic, Zootaxa 4442 (1), pp. 83-100 : 86-87

Perlesta browni Stark, 1989

Toothed Stone

http://lsid.speciesfile.org/urn:lsid: Plecoptera .speciesfile.org:TaxonName:1237

( Figs. 3‒4 & 11 )

Perlesta browni Stark 1989:279 . Holotype ♂ ( USNM), Rock Creek , Latimer Co., Oklahoma.

Perlesta browni: Poulton & Stewart 1991:39

Perlesta browni: Stark 2004:91

Perlesta browni: Kondratieff et al. 2011:300

Distribution. USA: AR, MO, OK, VA ( DeWalt et al. 2018)

Remarks. Adults of P. browni display golden-brown background color with darker pigmentation on the head, thorax ( Figs. 3a‒3d ), and abdomen. Whereas the abdominal terga for females are nearly uniform in color throughout their length, by comparison male terga 6‒10 are markedly darker than the anterior five segments. The posterolateral corners of the male 9th sternum are clothed by a dense matting of long hairs, noticeably longer and denser than the anterolateral and medial portions of the segment ( Fig. 4d ). Males have long, slender, tubular paraprocts with a mesoapical tooth ( Figs. 4a‒4c ) that are similar to sympatric P. cinctipes ( Figs. 5e‒5f ) but longer than those of P. armitagei sp. nov. ( Figs. 7a, 7c ). In addition, Poulton & Stewart (1991) showed that P. browni femora are pigmented only in the distal third, the brown color extending to the articulation with the tibia (their Fig. 344). Conversely, P. cinctipes femora are pigmented in approximately the middle 40%, the articulations with the coxae and tibiae are unpigmented ( Poulton & Stewart 1991, their Fig. 342).

Females can be separated by characteristics of their subgenital plate lobes and median notch ( Stark 2004). The eggs of P. browni are easily differentiated from P. cinctipes . The egg of P. browni has a short, slightly distallyflanged ribbed collar and the chorionic surface is covered by fine punctations except near the eclosion line ( Figs. 4e‒4f ; Stark 1989, his Fig. 15). The egg of P. cinctipes has a similar collar but the chorionic surface is coarsely pitted except for the smooth eclosion line region ( Stark 1989, his Fig. 17; Stark 2004, his Figs. 7.394‒7.396).

Perlesta browni was considered endemic to the Interior Highland region ( Fig. 11a ; Poulton & Stewart 1991, Stark 2004) until specimens seemingly indistinguishable from this species were reported from a single locality in eastern Virginia (Kondratieff et al. 2011). Perlesta browni is sympatric with P. cinctipes mainly in the Ouachita Mountain region of western Arkansas and eastern Oklahoma ( Fig. 11a ).

Figures

FIGURE 3. Perlesta browni. a–b, Arkansas, Fourche La Fave River; c–d, Arkansas, Ouachita River; a, c, male, head + pronotum, dorsal profile; b, d, female, head + pronotum, dorsal profile.

FIGURE 4. Perlesta browni, Arkansas, Fourche La Fave River. a, male, paraprocts, lateral view, 300X; b, male, paraprocts, caudal (left) and mostly lateral (right) views, 330X; c, male, right paraproct, lateral view 270X; d, male, 9 th sternum, 130X; e, egg, 330X; f, egg collar, anterior pole, 1100X.

FIGURE 5. Perlesta cinctipes. a–b, Arkansas, unknown locality; c–f, Missouri, South Moreau Creek; a, c, male, head + pronotum, dorsal profile; b, d, female, head + pronotum, dorsal profile; e, right paraproct, lateral view, 180X; f, right paraproct, lateral view, 330X.

FIGURE 7. Perlesta armitagei sp. nov., male.; a, Ohio, Deer Creek, male, 9 th sternum, 130X; b, Indiana, Blue River, right paraproct, lateral, 370X; c, Pennsylvania, French Creek, paraprocts, dorsal, 450X; d, Pennsylvania, French Creek, paraprocts, caudal, 330X.

FIGURE 11. Distribution maps of Perlesta based on material examined during this study. a, P. adena, P. browni, P. cinctipes, and P. xube; b, P. armitagei sp. nov. The record from northern West Virginia (red circle; Tarter & Nelson 2006) is conditional since that material was not available for study. The type locality is represented by the purple circle.