Perlesta armitagei n. sp. (Plecoptera: Perlidae): More cryptic diversity in darkly pigmented Perlesta from the eastern Nearctic
Grubbs, Scott A.
Dewalt, R. Edward
Zootaxa
2018
2018-06-29
4442
1
83
100
8N8PQ
Grubbs & Dewalt, 2018
Grubbs & Dewalt
2018
[151,370,1825,1851]
Insecta
Perlidae
Perlesta
GBIF
Animalia
Plecoptera
6
89
Arthropoda
species
armitagei
sp. nov.
http://lsid.speciesfile.org/urn:lsid:Plecoptera.speciesfile.org:TaxonName:502858 ( Figs. 6‒11) Description. Male forewing length 8.0‒10.0 mm (n = 29). Head pale yellow with a dark brown subquadrate ocellar patch and a small, light brown triangular patch anterior to the median ocellus, usually separated by a pale M-line; epicranial suture extends laterally, slightly beyond lateral ocelli ( Figs. 6a, 6c, 6e, 6g). Pronotum brown with a faint yellow medial stripe ( Figs. 6a, 6c, 6e, 6g). Female forewing length 10.0‒ 11.5 mm(n = 25). Color pattern similar to male but typically lighter and with less ocellar and epicranial suture pigmentation ( Figs. 6b, 6d, 6f, 6h). Wing membrane and veins amber except for pale white costal region. Femora brown dorsally extending to articulation with tibiae ( Figs. 6a‒6h), dorsum of tibiae brown. 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. Male( Figs. 6‒8). Sternum 9 ca. evenly and sparsely clothed by long hairs across most of the segment ( Fig. 7f). Abdominal terga brown, sterna yellow. Cerci pale yellow proximally, brown distally. Tergum 10 mesal sclerites brown, sensilla basiconica restricted to posterolateral margins with interspersed long hairs ( Figs. 7d‒7e). Paraprocts long and slender, bearing a prominent mesoapical tooth in lateral aspect and directed anteriorly, rounded apically ( Figs. 7a, 7c‒7d), not visible in caudal aspect ( Fig. 7b, 7e). Penis tube + sac long, caecum prominent and thumb-like ( Figs. 8a‒8c), sac nearly as long as tube ( Figs. 8a‒8b, 8e), lateral sclerite often lightly sclerotized, located in proximal ¼ of tube ( Fig. 8a), dorsal patch broad basally, narrowing apically throughout length of sac, completely covering caecum ( Figs. 8d‒8f). Female( Figs. 6, 9). Subgenital plate, ca. 1/2 width of 8th abdominal sternum ( Fig. 9a), lacking pigmentation; lobes subtruncate and rounded both medially and laterally ( Figs. 9b‒9d), with some populations with a slight concavity near medial corners ( Figs. 9b, 9d); lobes bordered posteriorly by a diffuse row of stiff bristle-like hairs; separated by an oval-shaped notch that is expanded medially ( Figs. 9b‒9d). Egg( Fig. 10). Oval. Collar distinctly stalked, wide, ribbed, and flanged at apex ( Figs. 10a‒10c). Chorion smooth with very fine shallow impressions visible only under high magnification ( Figs. 10a, 10d). Micropyles located ca. ¼ from anterior pole ( Fig. 10d). Larva. Unknown.
Type material. Holotypemale ( INHS): USA, Ohio, Ross Co., Deer Creek, 15 kmNNE Chillicothe, 39.46120, -83.02120, 28 June 2010, S.A. Grubbs. Paratypes: USA, Indiana, Bartholomew Co., East Fork White River, Azalia Bridge, 1.5 kmSW Azalia, 39.0849, -85.8598, 11 June 2000, S.A. Grubbs, 3 males, 3 females( WKUC); Daviess Co., East Fork White River, 14 kmS Washington, 38.5447, -87.2138, 7 June 2009, S.A. Grubbs, 8 males, 1 female( WKUC); Greene Co., West Fork White River, Rte. 157, 2 km SE Worthington, 39.1109, -86.9632, 7 June 2009, S.A. Grubbs, 3 males, 16 females( WKUC); Harrison Co., Blue River, 6 kmNE Leavenworth, Stagestop Canoe Access Site, Harrison-Crawford State Forest, 38.2153, -86.2718, 18 May 2000, S.A. Grubbs, 15 males, 7 females( WKUC); same but 9 June 2000, S.A. Grubbs, 2 males, 1 female( WKUC); Ohio River, Leavenworth, 38.1966, -86.3504, 28 June 2002, S.A. Grubbs, 3 males( WKUC); Jackson Co., Little Salt River, Houston, 39.0342, -86.1679, 22 June 2008, R.E. DeWalt, 1 male( INHS); Martin Co., East Fork White River, 2 kmNNE Shoals, 38.7013, -86.7674, 7 June 2009, S.A. Grubbs, 2 males, 4 females( WKUC); Washington Co., Blue River, Rte. 150, Fredericksburg, 38.4338, -86.1918, 28 June 2010, S.A. Grubbs, 3 males, 3 females( WKUC). Kentucky, Adair Co., Russell Creek, nr. Rte. 768, Milltown, 37.1235, -85.4046, 19 June 2008, S.A. Grubbs, 2 males, 5 females( WKUC); Green Co., Green River, at mouth of Big Pitman Creek, 7.5 kmSE Summersville, 37.2851, -85.5819, 22 May 2002, S.A. Grubbs, 4 males, 1 female( WKUC); Big Pitman Creek, Narrows of Pitman, 5 kmWNW Greensburg, 37.2833, -85.5576, 21 May 2002, S.A. Grubbs, 4 males, 5 females( WKUC). Ohio, Ross Co., same as holotype but 1 July 2007, S.A. Grubbs, 1 female( WKUC); same but 28 June 2010, S.A. Grubbs, 7 males, 9 females( WKUC). Pennsylvania, Crawford Co., French Creek, Meadville Access Site, 3 miSE Meadville, 41.5914, -80.1449, 10 June 1998, S.A. Grubbs, 14 males, 9 females( WKUC); same but 1 July 1998, S.A. Grubbs, 1 male( WKUC). Additional material examined. Indiana, Harrison Co., Blue River, White Cloud, 38.2290, -86.2254, 25 May 1949, W.E. Ricker, 1 male( CNCI). Kentucky, Fayette Co., Lexington, 7‒9 June 1970, 1 male( DCTC). Ohio, Butler Co., Seven Mile Creek, Hwy 127 Collinsville, 39.5050, -84.5946, 28 May 1953, A.R. Gaufin, 1 male, 1 female( BYU); Seven Mile Creek, New Miami, 39.4316, -84.5441, 28 May 1953, A.R. Gaufin, 1 male( BYU); Coshocton Co., Beaver Run, 2 kmNW Warsaw at Twp. 348 Bridge, 40.3495¸ -82.0134, 26 June 1999, S.W. Chordas IIIand J. Thompson, 1 male( INHS); Mohawk Creek, 0.5 kmE Mohawk Village at Co. Rd. 82 Bridge, 40.3205, -82.0741, 26 June 1999, S.W. Chordas IIIand J. Thompson, 2 males( INHS); Killbuck Creek, 2 kmNNW Randle at Co. Rd. 28 Bridge, 40.3338, -81.9457, 20 July 1999, S.W. Chordas IIIand J. Thompson, 1 male( INHS); Miami Co., Stillwater River, Hwy 718, 40.0521, -84.3659, 3 June 1953, A.R. Gaufin, 1 male( BYU); Warren Co., Little Miami River, Morrow, 39.3568, -84.1288, 28 June 1952, A.R. Gaufin, 1 male( BYU). Pennsylvania, Crawford Co., French Creek, SR 1002 bridge, Venango, 41.7716, -80.1083, 10 June 1991, S.A. Grubbs, 16 females( WKUC).
Etymology.This species is named in honor of Dr. Brian J. Armitage, former Director of the OhioBiological Survey and now “retired” in Boquete, Panama. Brian tirelessly performed design, layout, and other production activities for several books through the OhioBiological Survey and Caddis Press. He improved our understanding of the modern day composition and distribution of aquatic insects within Ohioand secured funding for statewide surveys of aquatic insects that trained several young entomologists. The common name “Brian’s Stone” is proposed for this species ( Stark et al. 2012).
Diagnosis.Males of P. armitageipossess a well-developed dorsal caecum ( Figs. 8a‒8c), which initially takes this species to couplet 2 in Stark (2004, pg. 88). The first choice in couplet 2 reads “epicranial suture arms extend well beyond ocelli as a distinct dark line” ( Stark 2004). Couplet 2, however, can be problematic for specimens that are lightly pigmented either due to (a) bleaching following long-term wet storage, or (b) adults preserved while still teneral. Five midwestern and Interior Highland species exhibit this characteristic: P. adena, P. baumanni Stark, 1989, P. cinctipes, P. fusca Poulton & Stewart, 1991, and P. xube. Material of P. adena( Figs. 1a, 1c, 1e), P. cinctipes( Figs. 5a, 5c), and P. xube( Figs. 2a, 2c, 2e) examined in this study exhibit this characteristic. Perlesta armitagei( Figs. 6a, 6c, 6e, 6g) and P. browni( Figs. 3a, 3c), however, generally lack this feature. Males of P. armitageiwill key most closely to P. decipiens( Walsh, 1862) in Stark (2004, see couplet 12)and Grubbs & DeWalt (2012, a modified couplet 12), with a paraproct spine visible in lateral view and directed forward ( Figs. 7a, 7c‒7d). Although the dorsal aedeagal patch of P. armitagei( Figs. 8d‒8e) is similar to P. decipiens( Stark 2004, his Fig. 7.306), the mesoapical paraproct tooth of P. armitagei( Fig. 7a, 7c) is easily contrasted from the antepical paraproct tooth of P. decipiens( Stark 1989, his Figs. 35‒36, 38‒41).
The paraprocts of P. armitagei( Fig. 7c) more closely resemble those of P. cinctipes( Figs. 5e‒5f) and P. browni( Figs. 4a‒4c) but are not as tubular or elongate as either species. Perlesta armitageiis more readily distinguished from P. cinctipesand P. browniby aedeagal characteristics. The aedeagi of P. armitageiand P. cinctipesare similar in that both species have a long tube + sac and well-developed caecum. The dorsal patch of P. cinctipesis very narrow ( Stark 2004, his Fig. 300) whereas the dorsal patch of P. armitageiis markedly wider ( Figs. 8d‒8e). Although the epicranial suture arms of P. browniextend little laterad of the ocelli ( Figs. 3a, 3c), and similar to P. armitagei( Figs. 6a, 6c, 6e, 6g), the aedeagi of the two species are distinct. The aedeagal tube + sac of P. browni( Stark 1989, his Fig. 80; Stark 2004, his Fig. 7.297) is much shorter than that of P. armitagei( Figs. 8a‒8b). FIGURE 9. Perlesta armitagei sp. nov., female, subgenital plate, ventral profile. a, Ohio, Deer Creek, 95X; b, Ohio, Deer Creek, 170X; c, Indiana, Blue River, 190X; d, Kentucky, Russell Creek, 170X. One additional male characteristic appears worthy of further study and may provide diagnostic information. On P. brownithe posterolateral corners of the male 9th sternum are clothed by a dense matting of long hairs ( Fig. 4d). These are visible under standard light microscopy and appear brush-like and denser than the remaining portions of the segment. In contrast, the male 9th sternum of P. armitageiis only sparsely clothed with long hairs ( Fig. 7f). The female of P. armitageican be confidently identified if mature eggs are present and associated with a male with a fully extruded aedeagus. Females will key to couplet 14 in Stark (2004), a dichotomy with P. shubuta Stark, 1989and P. decipiens. Perlesta ephelidaGrubbs & DeWalt, 2012also keys to couplet 14, but the subgenital plate of these three species are easily differentiated using standard light microscopy. The subgenital plate notch of P. armitageiis ovoid and expanded medially ( Figs. 9b‒9d). In contrast, the subgenital plate notches of P. ephelida(Grubbs & DeWalt 2012, their Fig. 7), P. shubuta( Stark 1989, his Fig. 91; Stark 2004, his Fig. 7.391), and P. decipiens( Stark 1989, his Figs. 44, 46, 48; Stark 2004, his Fig. 7.379) are variable but typically v-shaped. The egg is only partially diagnostic for P. armitagei. The egg of P. armitageipossesses a wide, well developed, and distally flanged collar ( Figs. 10a‒10c), resembling P. decipiens( Stark 1989, his Figs. 12‒13; Stark 2004, his Figs. 7.397‒7.398), P. ephelida(Grubbs & DeWalt 2012, their Figs. 14‒21), and P. mihucorum Kondratieff & Myers, 2011(their Figs. 9‒14), but easily contrasted from the coarsely and near-completely punctate egg chorion (except for the eclosion line) of P. cinctipes( Stark 1989, his Fig. 17; Stark 2004, his Figs. 7.394‒7.396). 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. Remarks.The typelocality is in southern Ohioat the southern edge of EPA Level IV Ecoregion 55b (Loamy, High Lime Till Plains). All streams where P. armitageihas been collected are mid-order systems with partially- to fully-open canopies. Allocapnia granulata( Claassen, 1924), A. vivipara( Claassen, 1924), and Taeniopteryx burksi Ricker & Ross, 1968were the only other stonefly species collected at the typelocality.
The plotted distribution of P. armitagei( Fig. 11b) is conditional since it only includes the specimens examined in this study. This distribution, however, suggests an OhioRiver basin species. We have not found this species during our extensive fieldwork and examination of museum material from Illinois(DeWalt & Grubbs 2011), Michigan(Grubbs et al. 2012), and Ontario(unpublished data). The plotted records from Indianamay represent the western edge the range.
The species reported as Perlestasp. I-4from Ohioin DeWalt et al.(2012, 2016) is now regarded as P. armitagei. The specimen determined as P. cinctipesfrom Kentucky(Fayette Co., Tarter et al.2006), and subsequently carried forward in the updated state checklist ( Tarter et al.2015), was reexamined and determined as P. armitagei. The specimens determined as P. cinctipesfrom West Virginia(Monongalia Co., Tarter & Nelson 2006) were not available for study but the location was still plotted ( Fig. 11b) and the inclusion in this map should be considered conditional.
1852083210
2010-06-28
INHS
S. A. Grubbs
United States of America
Ross Co.
39.4612
Deer Creek
1
-83.0212
8
91
1
Ohio
holotype
1852083309
2000-06-11
WKUC
S. A. Grubbs
United States of America
Bartholomew Co.
39.0849
Azalia Bridge
6
-85.8598
East Fork White River
8
91
6
3
3
Indiana
paratype
1852083211
2009-06-07
WKUC
S. A. Grubbs
United States of America
Daviess Co.
38.5447
East Fork White River
6
-87.2138
8
91
9
1
8
Washington
paratype
1852083209
2009-06-07
WKUC
S. A. Grubbs
United States of America
Greene Co.
39.1109
West Fork White River
6
-86.9632
West Fork White River
8
91
19
16
3
Washington
paratype
3071119307
2000-05-18
2000-06-09
2000-05-18
WKUC
S. A. Grubbs
United States of America
Harrison Co.
38.2153
Blue River
6
-86.2718
Blue River
8
91
22
7
15
Washington
paratype
3071119312
[650,1369,910,935]
2000-06-09
2000-06-09
2000-05-18
WKUC
S. A. Grubbs
United States of America
Harrison Co.
Stagestop Canoe Access Site
Blue River
8
91
3
1
2
Washington
paratype
1852083306
2002-06-28
WKUC
S. A. Grubbs
United States of America
38.1966
Ohio River
6
-86.3504
8
91
3
3
Ohio
paratype
1852083303
2008-06-22
INHS
R. E. DeWalt
United States of America
Jackson Co.
39.0342
Little Salt River
6
-86.1679
Little Salt River
8
91
1
1
Ohio
paratype
1852083310
2009-06-07
WKUC
S. A. Grubbs
United States of America
Martin Co.
38.7013
East Fork White River
6
-86.7674
East Fork White River
8
91
6
4
2
Ohio
paratype
1852083301
2010-06-28
WKUC
S. A. Grubbs
United States of America
Washington Co.
38.4338
Blue River
6
-86.1918
Rte.
8
91
6
3
3
Washington
paratype
1852083207
2008-06-19
WKUC
S. A. Grubbs
United States of America
Adair Co.
37.1235
Russell Creek
6
-85.4046
Russell Creek
8
91
7
5
2
Kentucky
paratype
1852083206
2002-05-22
WKUC
S. A. Grubbs
United States of America
Green Co.
37.2851
Green River, at mouth of Big Pitman Creek
6
-85.5819
Green River
8
91
5
1
4
Kentucky
paratype
1852083307
2002-05-21
WKUC
S. A. Grubbs
United States of America
Big Pitman Creek
37.2833
Big Pitman Creek
6
-85.5576
Narrows of Pitman
8
91
9
5
4
Kentucky
paratype
3071119313
[270,1231,1234,1259]
2007-07-01
2010-06-28
2007-07-01
WKUC
S. A. Grubbs
United States of America
Ross Co.
Deer Creek
15 km NNE Chillicothe
8
91
1
1
7
Ohio
holotype
3071119302
2010-06-28
2010-06-28
2007-07-01
WKUC
S. A. Grubbs
United States of America
Ross Co.
Deer Creek
15 km NNE Chillicothe
8
91
16
9
7
Ohio
holotype
3071119310
1998-06-10
1998-07-01
1998-06-10
WKUC
S. A. Grubbs
United States of America
Crawford Co.
41.5914
French Creek
6
-80.1449
French Creek
8
91
23
9
14
Pennsylvania
holotype
3071119308
1998-07-01
1998-07-01
1998-06-10
WKUC
S. A. Grubbs
United States of America
Crawford Co.
Meadville Access Site
French Creek
8
91
1
9
1
Pennsylvania
holotype
3071119304
1949-05-25
1970-06-09
1970-06-07
CNCI
W. E. Ricker
Harrison Co.
38.229
Blue River
6
-86.2254
Co. Rd.
8
91
1
16
1
Indiana
3071119309
[635,1437,1414,1439]
1970-06-07
1970-06-09
1970-06-07
DCTC
White Cloud & W. E. Ricker
Fayette Co.
Lexington
Co. Rd.
8
91
1
16
1
Kentucky
3071119305
1953-05-28
1970-06-09
1970-06-07
BYU
A. R. Gaufin
Butler Co.
39.505
Seven Mile Creek
6
-84.5946
Co. Rd.
8
91
2
1
1
Ohio
3071119314
1953-05-28
1970-06-09
1970-06-07
BYU
A. R. Gaufin
Harrison Co.
39.4316
Seven Mile Creek
6
-84.5441
Co. Rd.
8
91
1
16
1
Indiana
3071119301
1999-06-26
1970-06-09
1970-06-07
INHS
S. W. Chordas III & J. Thompson
Coshocton Co.
Beaver Run
Co. Rd.
8
91
1
16
1
Indiana
3071119311
1999-06-26
1970-06-09
1970-06-07
INHS
S. W. Chordas III & J. Thompson
Harrison Co.
40.3205
Mohawk Creek
6
-82.0741
Co. Rd.
8
91
2
16
2
Indiana
3071119303
1999-07-20
1970-06-09
1970-06-07
INHS
S. W. Chordas III & J. Thompson
Harrison Co.
40.3338
Killbuck Creek
6
-81.9457
Co. Rd.
8
91
1
16
1
Indiana
3071119306
1953-06-03
1970-06-09
1970-06-07
BYU
A. R. Gaufin
Miami Co.
40.0521
Stillwater River
6
-84.3659
Co. Rd.
8
91
1
16
1
Indiana
3071119315
[244,1437,1702,1727]
1952-06-28
1970-06-09
1970-06-07
BYU
A. R. Gaufin
Warren Co.
39.3568
Little Miami River, Morrow
6
-84.1288
Co. Rd.
8
91
1
16
1
Indiana
1852083208
1991-06-10
1970-06-09
1970-06-07
WKUC
S. A. Grubbs
Crawford Co.
41.7716
French Creek
6
-80.1083
Co. Rd.
8
91
16
16
1
Pennsylvania