Remenus Ricker 1952
Creators: name: Verdone, Chris J.
name: Kondratieff, Boris C.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Plecoptera
Perlodidae
Remenus

description: Genus <i>Remenus</i> Ricker, 1952 (Figs. 1, 3–18) Type species: <i>Perla bilobata</i> Needham &amp; Claassen (1925: 95) <i>Isogenus</i> (Remenus) Ricker (1952: 122) <i>Remenus</i>: Illies (1966: 376) <i>Remenus</i>: Hitchcock (1974: 214) <i>Remenus</i>: Stewart &amp; Stark (1984: 406) <i>Remenus</i>: Stewart &amp; Stark (1988: 402) <i>Remenus</i>: Kondratieff &amp; Nelson (1995: 596) <i>Remenus</i>: Stewart &amp; Stark (2002: 437) <i>Remenus</i>: Kondratieff (2004: 164) <i>Remenus</i>: Stark (2017: 236) <b>Male.</b> Macropterous; forewing length 9.1–11.0 mm (n = 40). Body length 7.9–10.6 mm (n = 40). General body color yellow-gold with light brown markings Fig. 1). Head as wide as, or wider than pronotum; crossveins (Fig. 4). Y-arms of mesosternum meeting posterior corners of furcal pits. Femora pale, light brown dorsally. Tibia pale, light brown dorsally. Tarsi light brown. Abdominal sterna pale to yellowgold; lobe on 7 th sternum well developed, lightly pigmented, narrowly rounded, apex rounded (Fig. 5); lobe on 8 th sternum reduced, ~ &amp;frac13; the size of lobe on sternum 7, triangular, lightly pigmented, apex acutely rounded (Fig. 5). Abdominal terga usually yellow-gold, with variable color pattern, covered in regularly spaced with setae; terga 8 and 9 with variable patches of sensilla basiconica (Fig. 6). Hemitergal lobes variously produced with long trichoid sensilla and various densities of sensilla basiconica (Fig. 6). Cerci pale, setose (Figs. 5–6). Lateral stylets absent. Epiproct variable, small, mostly membranous; with or without a mediodorsal sclerite (Fig. 7). Membranous portion covered in dense, minute hair-like spinulae. Paragenital plates flap-like, triangular or rounded (Figs. 6–7). Basal cowl clothed in dense variably pigmented spinulae (Fig. 7). Aedeagus entirely membranous with two lateral and two posterodorsal lobes (Figs. 5–7). <b>Female.</b> Macropterous; forewing length 9.4–12.0 mm (n = 40). Body length 8.8–12.6 mm (n = 40). General body coloration similar to male. Abdominal terga and sterna generally uniformly pale yellow. Subgenital plate broadly rounded or broadly triangular, produced over ½ sternum 9, or beyond (Fig. 8); with regularly spaced setae; a variable glabrous basolateral crease is present at the base of the subgenital plate and extends anteriorly up to &amp;frac13; into tergum 8 (Fig. 8). <b>Ovum.</b> Length 434–460 μm; width 324–361 μm (n = 12). Turtle-shaped with a ventrally positioned collar (Fig. 9). Mature ovum with a membranous covering, adorned with regularly spaced globules in clusters of 2–5 (Fig. 9). Dorsum of chorion smooth with very faint diamond-shaped follicle cell impressions. Dorsal keel extending from collar center to ovum center (Fig. 9). Collar with prominent diamondshaped follicle cell impressions dorsally and ventrally (Figs. 9–10). Ovum margin with a thickened raised edge. Micropyles positioned ventrally; arranged in a latitudinal row of 6 near the collar &amp;frac13; (Fig. 10). <b>Larva.</b> Body length 8.3–11.4 mm, (n = 19). Preserved specimen yellow-brown. Head wider than pronotum (Fig. 11); dorsum of head yellow- brown; frons with a faint, thin, pale M-shaped mark (Fig. 11); pale enclosed oval spots anterolateral of lateral ocelli, anterior of epicranial suture (Fig 11); large enclosed oval spots posterolateral of lateral ocelli, posterior of epicranial suture (Fig, 11); 2–4 postocular setae (Fig. 11); frontoclypeus unpigmented; labrum anterior margin with a setal fringe (Fig. 11); medial lobe of labrum with a dense fringe of golden setae. Lacinia unidentate (Fig. 12); lacinia sickle-shaped, tapering evenly from apical tooth and bearing stout, rounded, basal knob (Fig. 12); apical tooth with ~ 12 minute irregularly spaced setae extending halfway up the lacinia from the inner basal surface across the dorsal surface to the distal margin (Fig. 12). Basal knob with 5–6 submarginal minute setae (Fig. 12). Mandible with 5 teeth and without a deep cleft between the apical and subapical teeth (Fig. 13). Middle three teeth with proximal margins lightly serrated; dorsum of mandibles with a dense patch of stout setae (Fig. 13); proximal margin with a dense brush of stout setae on apical &amp;frac13; (Fig. 13). Maxillary palp slightly longer than lacinia (Fig. 14). Submental gills absent (Fig. 14). Pronotum yellow-brown; 10–16 long erect marginal setae on each side; lateral margins of pronotum brown (Fig. 11). Meso- and metanota yellow-brown; with 0–1 seta on either side of midline; 1–6 anterolateral setae (Fig. 15); wing pads with 1–7 marginal setae on proximal margin (Fig. 15). Y-arms of mesosternum reach the posterior corners of furcal pits. Femora pale yellow-brown with long stout setae over surface and without a dorsal fringe of silky setae. Tibia with short stout submarginal setae on dorsal and ventral surfaces and a dorsal fringe of silky setae. Tarsi with a short dorsal fringe of silky setae. Abdominal terga yellow-brown, with a posterior fringe of variable length setae (Fig. 16); longest setae ~ &amp;frac23; length of tergum; terga 1–2 without intercalary setae (Fig. 16); terga 4-10 with &lt;35 intercalary setae (Fig. 16). Abdominal sterna pale yellow-brown; sterna 1–2 without a posterior fringe or intercalary setae; sternum 3 occasionally with a single posterior seta laterally; sterna 4–8 with &lt;35 intercalary setae and a posterior fringe of variable length setae that is interrupted medially (Fig. 17); highest concentration of intercalary setae on abdominal segments 7–9 (Figs. 16–17); female 8 th sternum with a thin darkened strip posteromedially (Fig. 17); posterior fringe complete on sterna 9–10 (Fig. 17). Mature male larvae with an elongate terminal process (developing epiproct) with a constriction at the basal &amp;frac13;, apical &amp;frac23; thin and tapered (Fig. 18). Mature larvae with paired medial and lateral spots on the abdominal terga. Cerci with whorls of short or long setae, or a combination of both (Figs. 16, 18). <b>Diagnosis.</b> Regionally, <i>Remenus</i> is morphologically most similar to <i>Diploperla duplicata</i> (Banks, 1920). The two are often sympatric and share the following characters: (1) male tenth tergum partially cleft; (2) lobe on 7 th sternum well developed, narrowly rounded, and lobe on 8 th sternum reduced, ~ &amp;frac13; the size of lobe on 7 th sternum; (3) female subgenital plate broadly rounded with a membranous basolateral crease; (4) interocellular area enclosed with medium brown pigment that generally narrows towards the anterior ocellus and extends laterally from anterior ocellus to center of lateral ocelli; (5) larvae and adults lack submental gills; (6) larvae are similarly concolorous; (7) larvae have a dorsal fringe of setae on the tibia and lack a fringe on the femora; and (8) ova are turtle shaped. Adult males of <i>Remenus</i> are distinguished from <i>D. duplicata</i> by the presence of a well-developed epiproct and the lack of lateral stylets. Adult females of <i>Remenus</i> differ by the presence of distinct mesosternal Y-arms and &lt;3 cross veins in the apical costal space. Whereas <i>D. duplicata</i> has&gt; 5 cross veins in the apical costal space. Larvae of <i>Remenus</i> are easily distinguished from <i>D. duplicata</i> by their unidentate lacinia and well-developed mesosternal Y-arms. Ova of <i>Remenus</i> are also easily separated by their relatively smooth chorionic surface and the diamond-shaped follicle cell impression on the collar.
description: Published as part of <i>Verdone, Chris J. &amp; Kondratieff, Boris C., 2018, Holomorphology And Systematics Of The Eastern Nearctic Stonefly Genus Remenus Ricker (Plecoptera: Perlodidae), pp. 81-125 in Illiesia 14 (5)</i> on pages 89-92, DOI: 10.5281/zenodo.4757871
description: {"references": ["Ricker, W. E. 1952. Systematic studies in Plecoptera. Indiana University Publications Science Series, 18: 1 - 200. http: // www. nativefishlab. net / library / textpdf / 16 861. pdf", "Needham, J. G. &amp; P. W. Claassen. 1925. A Monograph of the Plecoptera or stoneflies of America north of Mexico. Thomas Say Foundation. 2: 1 - 397.", "Ricker, W. E. 1952. Systematic studies in Plecoptera. Indiana University Publications Science Series, 18: 1 - 200.", "Illies, J. 1966. Katalog der rezenten Plecoptera. Das Tierrech. Walter de Gruyter, Berlin, Germany.", "Hitchcock, S. W. 1974. Guide to the insects of Connecticut. Part VII. The Plecoptera or stoneflies of Connecticut. Bulletin of the State Geological and Natural History Survey of Connecticut, 107: 1 - 262.", "Stewart, K. W. &amp; B. P. Stark. 1984. Nymphs of North American Perlodinae genera (Plecoptera: Perlodidae). Great Basin Naturalist, 44: 373 - 415.", "Stewart, K. W. &amp; B. P. Stark. 1988. Nymphs of North American stonefly genera (Plecoptera). Entomological Society of America. Thomas Say Foundation Series, 12: 1 - 460.", "Kondratieff, B. C. &amp; C. H. Nelson. 1995. A review of the genus Remenus Ricker (Plecoptera: Perlodidae), with the description of two new species. Proceedings of the Entomological Society of Washington, 97 (3): 596 - 602.", "Stewart, K. W. &amp; B. P. Stark. 2002. Nymphs of North American stonefly genera, 2 nd ed. The Caddis Press. Columbus, Ohio. xii + 510 pp.", "Kondratieff, B. C. 2004. Perlodidae - Perlodinae (The Springflies). Pp. 149 - 180. In: B. P. Stark &amp; B. J. Armitage (eds.), The stoneflies (Plecoptera) of eastern North America. Volume II. Chloroperlidae, Perlidae, and Perlodidae (Perlodinae). Ohio Biological Survey Bulletin New Series Volume 14 (4): 1 - 192.", "Stark, B. P. 2017. Plecoptera. Pp. 161 - 247. In: J. C Morse, W. P. McCafferty, B. P. Stark, L. M Jacobus (eds.), Larvae of the Southeastern USA mayfly, stonefly, and caddisfly species. Biota of South Carolina. Vol. 9. Clemson University Public Service Publishing, Clemson University, Clemson, South Carolina, USA. 482 pp."]}