Perlesta xube Stark & Rhodes 1997

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

Perlesta xube Stark & Rhodes 1997

Pawnee Stone

http://lsid.speciesfile.org/urn:lsid: Plecoptera .speciesfile.org:TaxonName:1241

( Figs. 2 & 11 )

Perlesta xube Stark & Rhodes 1997:92 . Holotype ♂ ( USNM), Dry Creek, Merriman , Cherry Co., Nebraska.

Perlesta xube: Stark 2004:95

Distribution. USA: IA, IL, ND, NE, OH ( DeWalt et al. 2018), IN (new state record)

Remarks. The head masks of males and females of P. xube ( Figs. 2a‒2e ) are readily distinguished from P. armitagei sp. nov. ( Figs. 6a‒6h ) and P. cinctipes ( Figs. 5a‒5d ). The specimens (all males) determined as P. cinctipes in Stark (2004) were not of P. armitagei sp. nov. but of P. xube . Males of P. xube and P. cinctipes key to couplet 6 in Stark (2004). This couplet focuses on whether the dorsal patch is “wider at apex than at base” ( P. xube, Stark 2004 , his Fig. 7.370‒7.371) or “narrow throughout most of length” ( P. cinctipes, Stark 2004 , his Fig. 7.300). Perlesta cinctipes is one of few Perlesta species where the fully-extruded male aedeagus has yet to be illustrated with a line drawing or SEM. The length of the sac is not fully understood, whether in relation to the length of the tube or length and shape of the caecum. An additional aedeagal characteristic is useful in differentiating between these two species. The dorsal patch of P. xube is expanded at the base and body of the caecum but not apically ( Stark & Rhodes 1997, their Fig. 6 ; Stark 2004, his Figs. 7.370‒7.371). The dorsal patch of P. cinctipes , however, expands well onto the caecum ( Stark 2004, his Fig. 7.299).

Females of P. xube can be easily differentiated from P. cinctipes using Stark (2004) and from P. armitagei sp. nov. here with subgenital plate characteristics. Eggs of P. xube ( Stark & Rhodes 1997, their Fig. 8 , Stark 2004, his Fig. 7.404) are also distinct from both P. cinctipes ( Stark 1989, his Fig. 17, Stark 2004, his Fig. 7.394‒7.395) and P. armitagei sp. nov. ( Figs. 10a‒10d ).

Perlesta xube overlaps in distribution with P. armitagei sp. nov. from southern Indiana east to Ohio and with P. cinctipes to date only in southern Iowa ( Figs. 11a‒11b ).

Figures

FIGURE 2. Perlesta xube, a–b, Illinois, Little Saline River; c–d, Nebraska, Cherry Creek (paratypes); 11, Ohio, Pee Pee Creek. a, c, e, male, head + pronotum, dorsal profile; b, d, female, head + pronotum, dorsal profile.

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 6. Perlesta armitagei sp. nov. a–b, Ohio, Deer Creek; c–d, Indiana, Blue River; e–f, Kentucky, Russell Creek; g–h, Pennsylvania, French Creek; a, c, e, g, male, head + pronotum, dorsal profile; b, d, f, h. female, head + pronotum, dorsal profile.

FIGURE 8. Perlesta armitagei sp. nov., male, aedeagus. a, Ohio, Deer Creek, lateral; b, Indiana, Blue River, lateral, 95X; c, Ohio, Deer Creek, lateral, 200X; d, Ohio Deer Creek, dorsal, 220X; e, Ohio Deer Creek, dorsal; f, Pennsylvania, French Creek, details, of caecum, 950X.

FIGURE 10. Perlesta armitagei sp. nov., egg. a, Kentucky, Russell Creek, entire egg, 270X; b, Kentucky, Russell Creek, anterior pole and collar, 1600X; c, Ohio, Deer Creek, details of collar, 2300X; d, Kentucky, Russell Creek, posterior pole and micropyles, 500X.

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.