Simothraulopsis plesius Kluge 2007
Creators: name: Do, Jeane M. C.
name: Salles, Frederico F.
name: Hamada, Neusa
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Ephemeroptera
Leptophlebiidae
Simothraulopsis
Simothraulopsis plesius

description: Simothraulopsis plesius Kluge, 2007
(Figs 2 C, 3B, 9–13)
Simothraulopsis plesius Kluge 2007: 394; Mariano 2010: 134; Salles et al. 2010: 306.
Diagnosis. Male imago: 1) general coloration: thorax dark brown, abdomen purplish brown (Figs 9 A–C); 2) base of vein IMP attached to veins MP1 and MP2 (Fig. 10 A); 3) hind wing with costal projection almost forming a right angle located approximately 1/2 distance from base to apex of wing (Figs 10 B, C); 4) abdominal segments II–V with whitish basal bands (Figs 9 A); 5) penis projection lanceolate, of almost same width throughout most of its length, short (less than the half of total length of penis lobes) and slightly laterally directed (Fig. 10 D); 6) penis lobes fused on basal 1/4 (Fig. 10 D); 7) ventral region of penis lobes with a well-marked sclerotized region (Fig. 9 D). Mature nymph: 1) head with a yellowish stripe extending from median ocellus to labrum (Fig. 11 A); 2) femur III robust, about two times longer than wide (Figs 13 C); 3) posterolateral projections presents on abdominal segments V–IX, more developed on abdominal segments VIII and IX (Fig. 11 E); 4) grayish purple gills (Fig. 11 D).
Male imago. Length: body: 4.9–5.4 mm; forewing: 5.2–5.4 mm; hind wing: 0.5–0.7 mm. Head. Dorsal region brown, with black marks; ventral region whitish. Upper portion of compound eyes reddish, lower portion gray; ocelli whitish, surrounded by black. Scape of antenna brown, pedicel and flagellum translucent (Fig. 9 A).
Thorax. Pronotum dark brown with black marks. Mesonotum dark brown; longitudinal medial and medioparapsidal sutures yellowish; lateroparapsidal suture dark brown; posterior scutal protuberance, scutoscutellar impression and scutellum black. Pleura brown washed with yellow; membranous area grayish. Metanotum dark brown. Sterna yellowish, sutures brown. Wings membrane hyaline (Figs 10 A–C). Forewing with longitudinal veins whitish yellow and cross veins translucent; costal arms and base of veins C, Sc and anal section dark brown; fork of vein MP asymmetric; base of vein IMP attached to veins MP1 and MP2 (Fig. 10 A). Hind wing with costal projection developed, almost forming a right angle, located approximately 1/2 distance from base to apex of wing; veins brown, except base of vein C to costal projection and vein Sc dark brown; membrane almost completely colored, costal region blackish brown and lower portion of hind wing completely dark gray. Legs. Fore coxa dark brown, middle and hind coxa yellowish brown with dorsal and ventral marks black. Fore trochanter brown, middle and hind trochanters whitish. Leg I: femur with basal 2/3 orangish brown, apical 1/3 whitish; tibia with approximately basal half dark brown, apical half white; tarsi white. Legs II and III: femora whitish with a medial band purplish brown; tibiae black with a slender subapical gray band. Tarsi white.
Abdomen. Terga purplish brown, posterior margins darker. Laterobasal angles of terga II and III, basal 2/3 of tergum IV and slender basal band of tergum V translucent white; terga VI–IX with a medial black mark; tergum X whitish with a rounded mark (Fig. 9 A, B). Sterna I–IV translucent, others brown. Genitalia (Figs 9 D; 10D). Styliger plate grayish brown. Forceps segment I grayish brown, whitish on apex; segments II and III whitish. Segment II 0.08 length of segment I, 1.2 length of segment III. Penis lobes yellowish brown, fused on basal 1/4, inner margins divergent; each lobe rounded apically, with a lanceolate, of almost same width throughout most of its length, short (less than the half of total length of penis lobes) projection, slightly laterally directed; ventral region of penis lobes with a well-marked sclerotized region (Fig. 9 D). Caudal filaments whitish, except basal region brown and apical margin of each segment black.
Female imago. Length: body: 5–5.4 mm; forewing: 5.2–5.3 mm; hind wing: 0.6–0.9 mm. Color pattern similar to male imago, except coloration more purplish brown, abdomen without whitish bands. Sterna IX with lateral margins dark brown.
Mature nymph. Length: body, 4.8–5.3 mm; antenna, 3.5–3.8 mm; cerci, 4.4–4.5 mm; caudal filament, 5.3–5.5 mm. General coloration brown (Figs 11 A, B).
Head. Brown, with grayish marks; with a yellowish mark between compounded eyes and lateral ocelli and a yellowish stripe extending from median ocellus to labrum (these marks and stripe are more whitish in females). Upper portion of male compound eyes reddish brown, lower portion dark gray. Eyes of female black. Ocelli gray (Figs 11 A–C). Scape of antenna, pedicel and flagellum translucent white. Maximum width of labrum 1.12 times maximum width of clypeus. Labrum (Fig. 12 A) grayish brown, medial region with a yellowish stripe; with a pair of submedial, broad, well defined black marks on basal region; anteromedial emargination broad, with five denticles (outer denticles larger than the others). Mandible (Fig. 12 B) with basal half grayish brown, apical half yellowish translucent; with a rounded yellowish mark medially located; outer margin slightly curved, with 6–7 long, thick, filiform setae medially located. Maxilla (Fig. 12 C) yellow, outer margin grayish brown. Segment II of maxillary palpi 0.95 length of segment I, 1.98 length of segment III. Hypopharynx as in figure 12D. Labium as in figure 12E.
Thorax. Terga yellowish brown, with margins and marks dark gray; with a medial mark whitish yellow on pronotum and near anterior margin of mesonotum; anterior margin of pronotum with seven spines; metanotum brown; pleura grayish brown; sterna whitish yellow. Legs. Coxae brown with whitish marks; trochanters white, with light gray marks. Femora I and II white with medial and subapical brown bands; femur III brown washed with purple, except white marks on basal and medial areas. Femur III robust, about two times longer than wide (Fig. 13 C). Tibiae purplish brown on basal half, with a subapical brown band and apical whitish band. Tarsi whitish, with a brown basal band. Leg I (Fig. 13 A). Coxa and trochanter with pectinate setae. Femur: outer margin with apical half with long, stout setae and short stout setae; inner margin with few short stout setae; dorsal surface with spatulate setae; with pectinate setae near both inner and outer margins. Tibia: inner margin with stout setae; dorsal region with short stout setae near inner margin; outer margin with filiform setae. Tarsi with few short stout setae along inner margin and few filiform setae along outer margin. Leg II (Fig. 13 B). Coxa bare. Trochanter with lanceolate setae near apical region. Femur: outer margin with apical half with long stout setae; basal half with short stout setae; inner margin with short stout setae; dorsal surface with lanceolate and spatulate setae; basal region with pectinate setae. Tibia: inner margin bare, outer margin with filiform setae; dorsal region with short stout setae near inner margin. Tarsus: inner margin bare, outer margin with filiform setae. Leg III (Fig. 13 C). Coxa with filiform setae on apical region. Trochanter with few lanceolate setae. Femur: outer margin with short and median stout setae along its entire length; apical ¾ with long stout setae; dorsal surface with lanceolate and spatulate setae. Tibia: inner margin with stout setae and outer margin with filiform setae and few short stout setae. Tarsi: outer margin with filiform setae and stout setae, inner margin with stout setae.
Abdomen. Terga yellowish brown washed with gray, terga IV, V, VII and VIII with medial stripe lighter. Sterna whitish yellow, with brown marks near lateral margins. Gills grayish purple (Fig. 11 D). Posterolateral projections present on abdominal segments V–IX, however more developed on abdominal segments VIII and VIII (Fig. 11 E). Caudal filaments brown.
Life cycle association. Reared.
Comments. The distribution of S. plesius is currently restricted. In addition to its type locality in Peru, it was also collected in the Amazon biome (Fig. 49). Simothraulopsis plesius was previously recorded from Espírito Santo State by Salles et al. (2010), however, the specimens collected in this region correspond to Simothraulopsis caliginosus sp. nov., hence, S. plesius record in this state has not been confirmed. This species seems to be associated to small streams and was collected mainly on submerged logs and rarely in marginal vegetation.
Imagos and nymphs of S. plesius are similar to those of S. caliginosus sp. nov. given the general color pattern. Besides that, nymphs of both species possess posterolateral projections on abdominal segments V–IX. Nevertheless, they can be distinguished from each other by the differences in the penis lobes. In S. plesius the penis lobes are fused on basal ¼ and the inner margins are straight (Figs 9 D; 10D); in S. caliginosus sp. nov. the penis lobes are fused on basal half and the inner margins have a lobular area near fusion of lobes (Figs 29 D; 30D). Additionally, the membrane of the hind wings is almost completely pigmented in S. plesius (Fig. 10 C), and less pigmented in S. caliginosus sp. nov. (Fig. 30 C). Nymphs of both species can be separated from each other by the yellowish stripe extending from median ocellus to labrum present in S. plesius and absent in S. caliginosus sp. nov. (Figs 11 A; 31A) and by shape and arrangement of setae on the legs (Figs 13; 33).
Material examined: BRAZIL: Amazonas State: Barcelos: Jauari river, Comunidade Ucuqui (N 00°79'74.9"; W 63°50'11"; 50m) 26/ii/2009, Hamada N, Salles FF & Pes AM cols: 6 I ♂, 9 ♀, 15 N; Serrinha stream (N 00°24'29.7"; W 63°23'12.0"; 95m) Hamada N, Salles FF & Pes AM cols: 2 I ♂, 1 ♀, 8 N; Maniwau river (N 00°02'01.2"; W 62°47'25.7"; 48m) 28/ii/2009, Hamada N, Salles FF & Pes AM cols: 1 I ♂, 3 ♀, 2 N. Manaus: Br 147, Km 18,5 stream (S 02°49'0,8"; W 60°02'05,6"; 87m) 22/i/2009, Salles FF col: 1 I ♂; 22/i/2009, Salles FF col: 1 I ♂; 21/ix/2009, Salles FF & Boldrini R cols: 3 I ♂; 21/xii/2012, Salles F, Cruz PV & Boldrini R cols: 3 I ♂; 21/ xii/2012, Nascimento JMC, Salles FF, Boldrini R & Pes AMO cols: 5 I ♂, 6 N; ♂; 31/xii/2013, Nascimento JMC, Pes AMO & Silva JO cols: 6 I ♂, 8 N; 9 I ♀. Pará State: Alter do Chão, Camarão stream (S 02°30'12.4"; W 54°55'49.6"; 1m) 08/ix/2012, Nascimento JMC & Fernandes AS cols: 8 N; Sonrizal stream (S 02°32'02.8"; W 54°55'24.7"; 2m) 08/ix/2012, Nascimento JMC & Fernandes AS cols: 6 N.
description: Published as part of Do, Jeane M. C., Salles, Frederico F. & Hamada, Neusa, 2017, Systematics of Simothraulopsis Demoulin, 1966 (Ephemeroptera: Leptophlebiidae), pp. 1-81 in Zootaxa 4285 (1) on pages 16-23, DOI: 10.5281/zenodo.828100