Remenus kirchneri Kondratieff & Nelson, 1995

Verdone, Chris J. & Kondratieff, Boris C., 2018, Holomorphology And Systematics Of The Eastern Nearctic Stonefly Genus Remenus Ricker (Plecoptera: Perlodidae), Illiesia 14 (5), pp. 81-125 : 114-120

Remenus kirchneri Kondratieff & Nelson, 1995

( Figs. 1 , 92–113 )

http://lsid.speciesfile.org/urn:lsid: Plecoptera .speciesfile.org: TaxonName:606

Remenus kirchneri Kondratieff & Nelson (1995: 600) .

Holotype ♂: Virginia, Patrick County, Little Rock Castle Creek, Rock Castle Gorge National Recreation Area (NMNH). Figures: adult–male terminalia (dorsal, lateral), female subgenital plate.

Remenus kirchneri: Kondratieff (2004: 165) . Figures: adult–figures from Kondratieff & Nelson (1995).

Material examined: North Carolina, Avery Co., Jones Creek, Old Hanging Rock Rd., N 35.982213, W 82.01676, 22 June 2013, C. Verdone, B.C. Kondratieff, 1♂ ( CSUIC) . Wilkes Co., Garden Creek, Stone Mountain Rd., N 36.38905, W 81.06922, 29 May 2008, B.C. Kondratieff, R.F. Kirchner, R.E. Zuellig, D. R. Lenat, 2♂ ( CSUIC) . Tennessee, Carter Co., Roan Mountain State Park, [N 36.19623, W 82.07040], 2 June 2000, J. Enshinger, 1♂ ( CSUIC) . Virginia, Bedford Co., Battery Creek FR 951, N 37.55194, W 79.44059, 17 June 2016, C. Verdone, 2♂, 3♀ ( CSUIC) . Carroll Co., North Fork Stewarts Creek, Blue Ridge Parkway, BLRI, N 36.60630, W 80.81663, 11 May 2017, C. Verdone, B.C. Kondratieff, 11♂, 6♀, 6L ( CSUIC) ; Same location, 25 May 2017, C. Verdone, 3♂, 1♀ ( CSUIC) ; Pine Creek, nr. Jct. Co. Rd. 633 & Co. Rd. 640, N 36.66773, W 80.51043, 30 May 2016, C. Verdone, B.C. Kondratieff, 4♂, 2♀ ( CSUIC) ; tributary to Turkey Creek, Rte 620, N 36.61184, W 80.77082, 11 May 2017, 2♂, 6L ( CSUIC) . Floyd Co., Dodd Creek, Blue Ridge Parkway, BLRI, N 36.87178, W 80.27901, 31 May 2016, C. Verdone, B.C. Kondratieff, 1♂ ( CSUIC) ; small spring fed stream, 6 miles east of Floyd Rte 221, [no GPS] 28 June 1981, B.C. Kondratieff, 1♂, 1♀ ( CSUIC, paratype) ; spring fed stream, Blue Ridge Parkway, E. of Mt. Olivet Church, BLRI, N 37.11577, W 80.12949, 31 May 2016, C. Verdone, B.C. Kondratieff, 14♂, 19♀ ( CSUIC) ; Same location, 11 June 2016, C. Verdone, 5♂, 7 ♀ ( CSUIC) ; Same location, 9 May 2017, C. Verdone, B.C. Kondratieff. 38L ( CSUIC) ; Same data, [emerged 19 May 2017], 1♂, 1♀ ( CSUIC) ; Same data, [emerged 24 May 2017], 1♀ ( CSUIC) ; spring fed stream, Blue Ridge Parkway (spring house S of Rte 642) , BLRI, N 37.01133, W 80.12679, 31 May 2016, C. Verdone, B.C. Kondratieff, 1♂, 1♀ ( CSUIC) ; Spring tributary to Little River, Rte 706, N 36.98935, W 80.39589, 29 May 2016, C. Verdone, B.C. Kondratieff, 1♂, 2♀ ( CSUIC) ; tributary to Dodd Creek, Blue Ridge Parkway, BLRI, N 36.86353, W 80.28702, 31 May 2016, C. Verdone, B.C. Kondratieff, 13♂, 10♀ ( CSUIC) ; tributary to Dodd Creek, Blue Ridge Parkway, BLRI, N 36.8717, W 80.27943, 31 May 2016, C. Verdone, B.C. Kondratieff, 2♂ ( CSUIC) ; tributary to Little River, BLRI, N 37.01919, W 80.11913, 18–19 July 2007, C. R. Parker, 8♂, 6♀ ( CSUIC) ; tributary to Little River, Blue Ridge Parkway, N of Rte 642 "Poff", BLRI, N 37.01437, W 80.12343, 19 May 2017, C. Verdone, B.C. Kondratieff, S. Roble, 1♂, 3♀ ( CSUIC) ; tributary to Lick Fork, Blue Ridge Parkway, 0.9 mi. S of Rte 602, BLRI, N 37.11251, W 80.12924, 19 May 2017, C. Verdone, B.C. Kondratieff, S. Roble, 7♂, 4♀, 4L ( CSUIC) . Franklin Co., Brogan Branch, Rte 680/793, N 36.91700, W 80.19504, 31 May 2016, C. Verdone, B.C. Kondratieff, 1♂ ( CSUIC) . Patrick Co., Haunted Branch, Blue Ridge Parkway ~ 1 mi. S of Rte 634, BLRI, N 36.70024 W 80.44730, 9 May 2017, C. Verdone, B.C. Kondratieff, 15L ( CSUIC) ; Same location, 11 May 2017, C. Verdone, B.C. Kondratieff, 18L ( CSUIC) ; Same location, 19 May 2017, C. Verdone, B.C. Kondratieff, S. Roble, 2♂, 1♀ ( CSUIC) ; Little Rock Castle Creek, Rocky Knob Rec. Area, Rte 605, BLRI, N 36.80783, W 80.33112, 24 May 1994, B.C. Kondratieff, R.F. Kirchner, 1♂, 1♀ ( CSUIC) ; same location, 26 May 2016, C. Verdone, B.C. Kondratieff, 1♂, 2♀ ( CSUIC) ; Mayberry Creek, Blue Ridge Parkway, ~ 0.25 mi. S of Rte 634, BLRI, N 36.70842, W 80.44395, 26 May 2016, C. Verdone, B.C. Kondratieff, 6♂, 9♀ ( CSUIC) ; Same location, 9 May 2017, C. Verdone, B.C. Kondratieff, 1L ( CSUIC) ; small spring fed stream into [Talbott Reservoir], [no GPS], 2 August 1982, B.C. Kondratieff, 1♀ ( CSUIC, paratype) ; spring fed tributaries of [Rock Castle Creek] Rte 605, [N 36.80874, W 80.3255], 10 May 1983, B.C. Kondratieff, 1♂ ( CSUIC, paratype) ; tributary to Rock Castle Creek, Rte 605 at Cemetery, N 36.80874, W 80.3255, 26 May 2016, C. Verdone, B.C. Kondratieff, 8♂, 7♀ ( CSUIC) ; Same location, 9 May 2017, C. Verdone, B.C. Kondratieff, 10L ( CSUIC) ; Same location, 19 May 2017, C. Verdone, B.C. Kondratieff, S. Roble, 2♂, 3♀ ( CSUIC) . Roanoke Co., tributary to Back Creek, Blue Ridge Parkway, BLRI, N 37.18181, W 80.04742, 31 May 2016, C. Verdone, B.C. Kondratieff, 7♂, 12♀ ( CSUIC) ; tributary to Back Creek ; Blue Ridge Parkway, 0.5 mi. E of Rte 688 overpass, BLRI, N 37.19653, W 80.02029, 11 June 2016, C. Verdone, 2♂ ( CSUIC) .

Distribution. USA – NC, TN, VA ( Fig. 91 )

Male. ( Fig. 92 ). Macropterous; forewing length, 9.1– 10.5 mm (n = 10) ( Fig. 93 ). Body length, 8.2–10.2 mm (n = 10). General body color yellow-gold with light brown markings. Dorsum of head typical of genus ( Fig. 94 ). Pronotum light brown, covered in regularly spaced setae, with pale, glabrous rugosities mediolaterally ( Fig. 94 ); medial pale area slightly wider posteriorly ( Fig. 94 ). Abdominal terga yellow-gold with darkened anterior margins; rarely with darkened lateral margins. Tergum 9 with or without mediolateral patches of 3–5 sensilla basiconica ( Fig. 95 ). Hemitergal lobes short, not separated from 10 th tergum, with long trichoid sensilla and 12–20 sensilla basiconica on each lobe ( Figs. 95–97 ). Epiproct length ~ 270–500 μm; width ~ 20–59 μm (n = 3); epiproct dorsoventrally flattened, tongue-shaped and lightly sclerotized ( Figs. 95-96 , 98–100 ); covered in dense, thick hair-like spinulae ( Fig. 100 ); when produced forward, exceeding the anterior margin of the basal sclerite. Paragenital plates triangular ( Figs. 95 , 98 ). Basal cowl covered in dense lightly pigmented spinulae ( Figs. 95–96 ).

Female. Macropterous; forewing length 10.0– 11.9 mm (n = 10). Body length, 9.2–12.6 mm (n = 10). General color and morphology similar to the male. Abdominal terga pale, without darkened anterior or lateral margins. Subgenital plate broadly rounded ( Fig. 101–102 ), occasionally with a shallow posteromedial emargination ( Fig. 102 ), or broadly triangular ( Fig. 103 ); lightly sclerotized, with regularly spaced setae, extending ½–⅘ over sternum 9; posterolateral margins convex; basolateral margins typically parallel; basolateral crease typically curved, concave posteriorly, extending ~ ¼ length anteriorly into sternum 8 ( Figs. 101–103 ).

Ovum. Shape typical of genus ( Figs. 104–107 ). Length 438–460 μm; width 348–353 μm.

Larva. ( Fig. 108 ). Body length 8.5–11.4 mm, (n = 10). Head ( Fig. 109 ), lacinia ( Fig. 110 ), mandibles ( Fig. 111 ), and pronotum ( Fig. 109 ) typical of genus. Mature male larva with a short terminal process (developing epiproct) with a constriction at the basal ⅓; apical ⅔ tapering to a narrowly rounded apex ( Fig. 112 ). Basal cercal segments with whorls of short setae ( Fig. 113 ).

Diagnosis. Males of R. kirchneri are morphologically similar R. daniellae . Males possess a tongue-shaped epiproct in dorsal aspect, which is widest medially or near the basal ¼ and is dorsoventrally flattened. Whereas the epiproct of R. daniellae is clavate, is widest towards the apical ¼ and narrows posteriorly both in dorsal and lateral aspects. Additionally, the epiproct of R. daniellae typically possesses a short translucent tube at the apex, which R. kirchneri lacks. Furthermore, R. kirchneri generally has sensilla basiconica on tergum 9 and consistently has 12–20 sensilla basiconica on each hemitergal lobe. In contrast, R. daniellae generally lacks sensilla basiconica on tergum 9 and has <4 minute sensilla basiconica on each hemitergal lobe.

Females of R. kirchneri are most similar to R. daniellae . Separation of these species may require associated males. Generally, the subgenital plate of R. kirchneri is parallel sided basally, whereas in R. daniellae , the subgenital plate is typically convergent. Based on presently available records, the ranges of these two species do not overlap, as previously mentioned. As such, morphology paired with geographic location should help inform identification of these two similar species.

Mature larvae of R. kirchneri are separable from the other sympatric species, R. bilobatus , by the lack of long setae on the basal cercal segments. Remenus duffieldi also lacks long setae on the basal cercal segments, but it does not occur east of the French Broad River ( Fig. 115 ).

Biological notes. Prior to this study R. kirchneri was known from six locations in Virginia, one in North Carolina and one in Tennessee. Despite considerable effort, we were unable to find this species in either year in North Carolina or Tennessee. However, R. kirchneri proved to be a frequent inhabitant of headwater streams along the Blue Ridge Parkway in southern Virginia. This species is now known from 25 locations ranging from Bedford County, Virginia to Carter County, Tennessee. Remenus kirchneri occurs in the Blue Ridge Physiographic Province in 1 st –3 rd order streams with drainage areas ranging in size from 0.09–8.75 km 2. The average elevation of occurrence localities is 717.8 m (SD ± 163.5 m). Based on the material examined, emergence begins in mid-May and continues until early August.

This species can achieve moderate benthic densities ranging from 11–161/m 2 (n = 12) despite apparently low fecundity. Females collected from a spring fed stream, along the Blue Ridge Parkway near Mt. Olivet Church, were kept alive in ventilated plastic jars with moistened paper towels (and no food) so that they might mate and produce eggs. In total, only three females produced eggs, each consisting of a single clutch of 59–61 ova. However, ova dissected from another female numbered 134. The ova were not fully formed and may have numbered more if fully developed. Possibly R. kirchneri produces several clutches of ova, or may need to feed to do so. Other similarly sized perlodids are known to produce egg masses ranging in size from ~ 90 to 1000 ova ( Peckarsky & Cowan 1991, Tierno De Figueroa et al. 2000, Sandberg & Stewart 2001, Tierno De Figueroa & López-Rodríguez 2005).

Figures

Figure 108. Larval habitus of Remenus kirchneri, tributary to Rock Castle Creek, Patrick County, Virginia.

Fig. 1. Remenus kirchneri, spring fed stream, Blue Ridge Parkway, east of Mt. Olivet Church, Floyd County, Virginia.

Fig. 92. Adult male habitus of Remenus kirchneri, tributary to Dodd Creek, Floyd County, Virginia.

Figs. 93–96. Remenus kirchneri, adult male. 93. Right forewing, spring fed stream, Floyd County, Virginia. 94. Head and pronotum, tributary to Dodd Creek, Floyd County, Virginia. 95–96. Tributary to Rock Castle Creek, Patrick County, Virginia. 95. Terminalia, dorsal. 96. Terminalia, lateral.

Figs. 97–100. Remenus kirchneri, adult male, tributary to Dodd Creek, Floyd County, Virginia. 97. Hemitergal lobe. 98. Epiproct dorsal. 99. Epiproct dorsolateral. 100. Epiproct, hair-like setae, dorsolateral.

Figs. 101–103. Remenus kirchneri, adult female, subgenital plate variation. 101. Tributary to Rock Castle Creek, Patrick County, Virginia. 102. Tributary to Lick Fork, Floyd County, Virginia. 103. Tributary to Dodd Creek, Floyd County, Virginia.

Figs. 104–107. Remenus kirchneri, ovum, spring fed stream, Floyd County, Virginia. 104. Ovum with membranous covering, dorsal. 105. Ovum, bare, dorsal. 106. Collar, ventral. 107. Micropyles, ventral.

Figs. 109–112. Remenus kirchneri, larva. 109. Head and pronotum, tributary to Rock Castle Creek, Patrick County, Virginia. 110–112. Spring fed stream, Floyd County, Virginia. 110. Left lacinia, dorsal. 111. Left mandible, dorsal. 112. Male terminal process (developing epiproct), ventral.

Fig. 113. Remenus kirchneri, larval cercus, dorsal, tributary to Rock Castle Creek, Patrick County, Virginia.

Fig. 91. Remenus kirchneri, distribution of examined material and published records.

Fig. 115. Distribution of Remenus daniellae, R. duffieldi, and R. kirchneri in the Blue Ridge Physiographic Province.