Traverella excelsior Nascimento & Lima & Mariano & Azevêdo 2020, sp. nov.
Creators: name: Nascimento, Stênio R. S.
name: Lima, Lucas R. C.
name: Mariano, Rodolfo
name: Azevêdo, Carlos A. S.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Ephemeroptera
Leptophlebiidae
Traverella
Traverella excelsior

description: Traverella excelsior Nascimento & Lima sp. nov.
(Figs 1–5)
Diagnosis. Traverella excelsior sp. nov. can be distinguished from its congeners by the following differential characters: male imago: 1) forks of MA and MP veins asymmetric, ICu1 basally free (Fig. 2A); 2) styliger plate with lateral projections sharpening toward apex and with cavity from the inner base to the apex of forceps, covering almost entirely the penes lobes (Figs 1D, 2D); 3) penes lobes with a ventrally projected at apex (Figs 1E, 2E); 4) subapical spines with broad base, tapering toward the apex and medially curved and inserted in a groove into each penes lobes (Fig. 2E). Nymph: 1) clypeus without an anteromedial projection, lateral margin strongly concave, maximum width of labrum 1.3× maximum width of clypeus; 2) labrum U-shaped with anteromedial emargination; dorsal proximal row with 13–15 long setae interrupted medially; 3) mandible with a median rounded area on inner margin; outer margin basally curved; 4) gills present on segments I–VII tapering gradually, with no lateral tracheation, inner margin with 6–8 filaments along the entire length of gill and outer margin apically with 3–4 filaments.
Description. Male imago (in alcohol). Length: body: 5.9–6.7 mm; forewing: 6.8–6.9 mm; hind wing: 1.03–1.2 mm.
Head. Dorsal region light brown, with dark brown markings; ventral region whitish (Fig. 1B). Upper portion of composite eye orange-brown, lower portion black; ocelli whitish, surrounded by dark brown (Figs 1A, B). Antenna. Scape and pedicel light brown, flagellum yellowish (Fig. 1B).
Thorax. Pronotum dark brown washed with black, with posterior margin dark brown and, medially with light brown band (Fig. 1C). Mesonotum dark brown, except for mediolongitudinal, medioparapsidal and lateroparapidal sutures light brown, posterior scutal protuberance and scuto-scutellar impression dark brown, scutellum light brown (Figs 1A, C). Metanotum light brown; pleura yellowish-brown with dark brown sclerites; sternum light brown (Figs 1A, C). Wings (Figs 2 A–C). Membrane hyaline, stained with brown at base. Forewing with yellowish longitudinal veins yellowish and crossveins translucent, forks of MA and MP veins asymmetrics, ICu1 basally free (Fig. 2A). Hind wing with hyaline membrane, brown at base, costal projection well-developed, forming acute angle, veins translucent (Figs 2B, C). Legs. Forecoxa dark brown, median and posterior yellowish-brown. Trochanters yellowish-brown. Foreleg with femur yellowish-brown with small brown band, washed with black at apex; tarsus yellowish-brown. Mid and hind legs: femora yellowish-brown with dark brown band washed with black at apex; tarsi yellowish-brown.
Abdomen. Tergum I dark brown, washed with black, terga II–VI translucent, posterior margin of terga III–IX with transversal dark brown band, laterally interrupted; terga VII–X light brown, tergum X darker (Figs 1A, C). Sterna I–VI translucent, segments VII–IX light brown. Genitalia (Figs 1D, E; 2D, E). Styliger plate yellowishbrown, with small, median projection; lateral projections sharpening toward at apex and with cavity from inner base to apex of forceps, covering penes lobes almost entirely when observed in ventral view (Figs 1D, 2D). Forceps yellowish-white, segment II 0.16× length of segment I (Figs 1D, 2D). Penes dark brown, broad at base and apically rounded, with lobes fused at basal ¼ and ventral projection at apex, ventrally projected at apex; subapical spines light brown with broad base, tapering toward apex and medially curved and inserted in groove into each penes lobe (Fig. 2E). Caudal filaments whitish with apical margin of each segment black.
Mature Nymph. Length: body, 5.9–6.6 mm; antenna, 3.6– 3.5 mm; cerci, 7.1–7.3 mm; terminal filament, 8.2– 8.7 mm. General coloration brown (Figs 3–5).
Head. Light brown, washed with gray. Upper portion of male compound eye reddish brown, lower portion black. Antenna whitish yellow. Clypeus without anteromedial projection (Fig. 4A), lateral margin strongly concave, maximum width of labrum 1.3× maximum width of clypeus. Mouthparts (Figs 4 A–E). Labrum (Fig. 4A) dark brown, U-shaped with anteromedial emargination; dorsal proximal row with 13–15 long setae, interrupted medially; numerous ventral setae directed obliquely to sagittal plane; maximum width 2.5× maximum length. Mandible (Fig. 4D) translucent, dark brown near to incisors and molars, with median brownish rounded area on inner margin; outer margin basally curved; without dorsal row of setae and with thick and long setae near to basal articulation. Maxilla (Fig. 4E). Galea-lacinia with prominent tusk on inner apical angle (nearly half of apical width of galea-lacinia). Hypopharynx as in figure 4B. Labium as in figure 4C.
Thorax. Terga yellowish brown, irregularly washed with dark gray; pronotum with submedial stripe and lateral margin dark gray; pleura brownish, washed with dark gray; sterna whitish yellow (Fig. 3B). Legs. Whitish; coxae washed with dark gray. Leg I (Fig. 5A). Femur with subapical band and dorsal blackish mark. Legs II and III (Figs 5B, D) similar to leg I slightly washed with light brown. Femora with long setae and spine-like setae along external margin; dorsal surface covered with long spine-like setae, absent in femur I. Tibia I (Fig. 5A) with few short spinelike setae along inner margin and long spine-like setae on dorsal surface, long and thin setae along outer margin; tibia II (Fig. 5B) with long and thin setae along outer margin and row of spine-like setae on dorsal surface; tibia III (Fig. 5C) with spine-like setae and long setae in external margin and long spine-like setae on dorsal surface and inner and apical margins. Tarsal claws strongly hooked (Fig. 5E) with minute denticles basally and 6–7 median denticles subequal in size, without accessory denticles.
Abdomen. Terga brown, segments VI–X darker; segment I washed with gray. Sterna whitish, segments VII–X darker (Fig. 3B). Gills grayish, present on segments I–VII tapering gradually, with no lateral tracheation (Fig. 5C); inner margin with 6–8 filaments along entire length of gill and outer margin apically with 3–4 filaments. Caudal filaments yellowish.
Female imago. Unknown.
Life cycle association. Nymphs reared.
Biology. The nymphs were captured inhabiting leaves and rocks about 1 m below the water surface, on the banks of Rio Itapecuru. The river flows through highly impacted agricultural land and pasture. The river receives the wastewaters from Caxias municipality and all communities upstream, and many people use the river for laundry, bathing, and fishing.
Etymology. In memory of the famous comic book writer, Stanley Martin Lieber ‘Stan Lee’ (1922–2018), whose expression “Excelsior!” (word of Latin origin meaning something illustrious, grandiose, majestic) found special popularity.
Material examined. Holotype: ♂ imago (reared), exuviae mounted on slides, Brazil, Maranhão State, Cax- ias municipality, Pé da Serra, Rio Itapecuru, S05°07’28.51”, W43°33’02.26”, 68 m a.s.l., 06.xii.2019, Nascimento, SRS; Jesus, JIS cols. (UFVB–EP00193). Paratypes: Brazil, Maranhão State, 3 ♂ imagos (UFVB–EP00194), same data as holotype, except 31.i.2014, Nascimento, SRS; Gomes, GRD; Diego, DC cols, light trap; 1 ♂ imago (MZUESC–eph0700), same data as holotype, except 06.vii.2014, Nascimento, SRS; Gomes, GRD; Diego, DC cols, light trap; 3 ♂ imagos (MZUESC–eph0701), same data as holotype, except 08.iii.2018, Nascimento, SRS; Jesus, JIS cols, light trap; 5 ♂ nymphs (UFVB–EP00195), same data as holotype, except 02.ii.2014, Nascimento, SRS; Gomes, GRD; Diego, DC cols; 1 ♂ nymph (MZUESC–eph0702), same data as holotype, except 06.xii.2019, Nascimento, SRS; Jesus, JIS cols.
Discussion. The male imago of T. excelsior sp. nov. is similar to T. (Zonda) calingastensis from Western Argen- tina by sharing the same pattern of coloration on body and wings, and styliger plate with broad and paired projections. However, the new species differs from it by having a styliger plate very unusual for the genus, with lateral projections apically pointed and laterally curved, and a small medial projection posteriorly projected. The subapical spine of penes lobe is also uncommon with broad base, tapering toward the apex and medially curved and inserted in a groove into each penes lobe. The nymphal stage is similar to T. insolita by the presence of a prominent tusk on galea-lacinia and a row of spine-like setae on the foretibia, and absence of a frontoclypeal projection. They can be distinguished from each other by the ratio of width/length of labrum: 2.8× in T. insolita and 2.5× in T. excelsior sp. nov.
description: Published as part of Nascimento, Stênio R. S., Lima, Lucas R. C., Mariano, Rodolfo & Azevêdo, Carlos A. S., 2020, New species and stages description of Traverella Edmunds, 1948 (Ephemeroptera Leptophlebiidae) from Northeast Brazil, pp. 411-422 in Zootaxa 4861 (3) on pages 412-417, DOI: 10.11646/zootaxa.4861.3.7, http://zenodo.org/record/4416461