Simothraulopsis inaequalis, Do, Jeane M. C., Salles, Frederico F. & Hamada, Neusa, 2017

Do, Jeane M. C., Salles, Frederico F. & Hamada, Neusa, 2017, Systematics of Simothraulopsis Demoulin, 1966 (Ephemeroptera: Leptophlebiidae), Zootaxa 4285 (1), pp. 1-81 : 65-74

Simothraulopsis inaequalis sp. nov.

( Figs 44–48 )

Diagnosis. Male imago: 1) general coloration: orangish, abdomen washed with light brown ( Figs 44 A, B); 2) hind wing with costal projection almost forming a right angle, located approximately 2/3 distance from base to apex of wing ( Figs 45 B, C); 3) abdominal segments with color pattern different from the other species of the genus, without whitish bands on basal region ( Figs 44 A–C); 4) tergum IX almost completely black; 5) penis projection lanceolate, narrowing towards apex, short (less than the half of total length of penis lobes) and laterally directed ( Figs 44 D, 45D); 6) penis lobes fused on basal 1/3 ( Fig. 45 D); 7) ventral region of penis lobes with a well-marked sclerotized region ( Fig. 44 D). Mature nymph: 1) with a yellowish stripe extending from median ocellus to labrum ( Figs 46 A, C); 2) abdominal tergum IX almost completely black ( Figs 46 A, C); 3) femur III robust, about two times longer than wide ( Fig. 48 C); 4) posterolateral projections presents on abdominal segments V–IX ( Fig. 46 D); 5) gills violet with dark gray margin ( Fig. 46 E).

Male imago. Length: body: 7.2 mm; forewing: 7.6 mm; hind wing: 0.9 mm.

Head. Dorsal region orangish, with irregular dark gray marks; ventral region yellowish orange, with gray marks. Upper portion of compound eyes reddish brown, lower portion dark gray; ocelli whitish gray, surrounded by dark gray ( Figs 44 A, B). Scape of antenna orangish, pedicel orange washed with brown, flagellum translucent yellow.

Thorax. Pronotum orangish, surrounded by grayish brown; with medial and submedial brown stripes. Mesonotum yellowish orange; medial longitudinal suture whitish yellow; anterolateral scutal, lateroparapsidal and medioparapsidal sutures brown; posterior scutal protuberance slightly washed with yellowish brown; scutoscutellar impression dark brown. Pleura brownish orange, irregularly washed with grayish brown. Sterna yellowish white ( Figs 44 A, B). Wings membrane translucent yellow ( Figs 45 A–C). Forewing with longitudinal veins brownish yellow and cross veins brown; costal arm and base of veins C, Sc and R1 dark brown; fork of vein MP asymmetric ( Fig. 45 A). Hind wing with costal projection developed, almost forming a right angle, located approximately 2/3 distance from base to apex of wing ( Figs 45 B, C); longitudinal and cross veins brown, except base of vein C to costal projection dark brownish orange; costal region grayish yellow and almost the entire lower portion of hind wing black, except basal area translucent. Legs. Coxae and trochanters brownish orange. Leg I: femur orange washed with brown; tibia orangish brown; tarsus whitish, with distal region of tarsomeres grayish. Legs II and III: femora orangish washed with brown; tibiae whitish. Femur II with basal region whitish yellow. Tarsi white.

Abdomen. Terga orangish, washed with light brown; posterior margins grayish brown ( Figs 44 A, B). Tergum I almost completely brown, except submedial region yellowish; terga II and III with submedial region dark gray; tergum VIII with a submedial black mark near posterior margin; tergum IX almost completely black, except medial region, posterior and lateral margins orangish; tergum X with an anterolateral rounded black mark. Sterna orangish, with anterior margins translucent; sternum I whitish; sternum IX washed with brown. Genitalia ( Figs 44 D, 45D). Styliger plate brownish orange. Forceps segment I brownish orange, with inner margin dark brown, segments II and III whitish yellow. Segment II 0.10 length of segment I, 1.9 length of segment III. Penis lobes whitish brown, fused on basal 1/3, inner margins divergent; each lobe rounded apically, with a short (less than the half of total length of penis lobes), lanceolate projection, laterally directed and narrowing towards apex; ventral region of penis lobes with a well-marked sclerotized region ( Fig. 44 D). Caudal filaments whitish, except basal region brown and apical margin of each segment light brown.

Female imago. Length: body: 7.5–8 mm; forewing: 7.9–8.1 mm; hind wing: 0.9–1 mm. Color pattern similar to male imago, except by coloration more yellowish. Sterna IX with lateral margins dark brown ( Fig. 44 C).

Mature nymph. Length: body, 9.3–10.2 mm; antenna, 3.9–4.2 mm; cerci, 10.8–11 mm; caudal filament, 11.1– 11.3 mm. General coloration yellowish brown ( Figs 46 ).

Head. Brown, with a yellowish stripe extending from median ocellus to labrum; with a rounded, whitish yellow mark located between lateral ocelli and compound eyes. Upper portion of male compound eyes reddish brown, lower portion black. Eyes of female black. Ocelli gray, surrounded with black ( Figs 46 A–C). Scape and pedicel of antenna whitish, flagellum brownish yellow. Maximum width of labrum 1.22 times maximum width of clypeus. Labrum ( Fig. 47 A) grayish brown, medial region with a yellow stripe; anteromedial emargination broad, with five denticles of equal size; with a pair of submedial, well defined black marks on basal region. Mandible ( Fig. 47 B) orangish brown, translucent near to basal articulation and apical region (except incisors and molar area orangish); with a rounded, white mark medially located; outer margin slightly curved, with 9–12 filiform, long, thick setae medially located. Maxilla ( Fig. 47 C) yellowish translucent, outer margin brown, with dark gray marks. Segment II of maxillary palpi 1.2 length of segment I, 2.1 length of segment III. Hypopharynx as in figure 47D. Labium as in figure 47E.

Thorax. Terga orangish brown, irregularly washed with dark gray; pronotum with an anterosubmedial mark and anterolateral region whitish, anterior margin with 6–7 spines; pleura yellowish, washed with brown; sterna whitish yellow ( Figs 46 A–C). Legs. General coloration yellowish; coxae and trochanters brown; femora with a medial and submedial brown bands; tibiae slightly washed with brown, with a subapical dark brown band; tarsi with a sub-basal brown band. Femur III robust, about two times longer than wide ( Fig. 48 C). Leg I ( Fig. 48 A).

Coxa with filiform setae. Trochanter with pectinate setae near inner margin. Femur: outer margin with basal half with short stout setae, apical half with long, stout setae; inner margin with lanceolate setae; dorsal surface with pectinate, filiform and spatulate setae. Tibia: inner margin with short stout setae. Tarsus with few filiform thick setae along inner margin. Leg II ( Fig. 48 B). Coxa bare. Trochanter with short lanceolate setae. Femur: outer margin with basal half with short stout setae, apical half with long stout setae; inner margin with stout setae; dorsal surface with lanceolate, spatulate and stout setae. Tibia: inner margin with stout setae, outer margin with filiform setae. Tarsi with few stout setae along inner margin and filiform setae along outer margin. Leg III ( Fig. 48 C). Coxa bare. Trochanter with lanceolate setae. Femur: outer margin with basal half with stout setae, apical half with long stout setae; inner margin with short stout setae; dorsal surface with spatulate, lanceolate and stout setae. Tibia: inner margin with stout setae, outer margin with long, spatulate setae slightly acute at apex. Tarsus with few stout setae along inner and outer margin.

Abdomen. Terga orangish brown slightly washed with yellow; terga III, IV and VI–VIII with medial region yellowish; posterior margin of tergum VIII black; tergum IX almost completely black, except medial region and posterior margin whitish yellow; tergum X with an anterolateral rounded gray mark. Sterna whitish yellow ( Figs 46 A–C). Gill violet, with dark gray margins; tracheal region grayish ( Fig. 46 E). Posterolateral projections present on abdominal segments V–IX, VII–IX more developed ( Fig. 46 D). Caudal filaments yellowish, basal area brown.

Life cycle association. Reared.

Etymology. From the Latin word inaequalis , different; a reference to the body color pattern very different from the general color pattern of the genus.

Comments. Simothraulopsis inaequalis sp. nov. seems to be restricted to the Amazon biome ( Fig. 49 ). The nymphs were collected in small streams and most often found in submerged logs and are camouflaged by their color.

This is the most distinctive species of the genus and can be separated from the others species by the following combination of characters: large size of nymphs and imagos (about 8 mm and 10 mm, respectively); body color pattern ( Figs 44 ; 36); hind wing with distal margin truncated ( Fig. 45 C), and nymphs with large and wide gills ( Figs 46 A, B, E). S. inaequalis sp. nov. is somewhat similar to S. plesius and S. caliginosus sp. nov. Nymphs of these species have posterolateral projections present on abdominal segments V-IX ( Figs 11 E; 31D; 46D), labrum with a pair of submedial well defined marks ( Figs 12 A; 32D; 47D), hind femur robust (about two times longer than wide) ( Figs 13 A; 33D; 48D), and pronotum with a broad whitish distal mark ( Figs 11 A; 31D; 46D). In male imagos, the projection of the penis lobes is lanceolate, narrowing towards apex ( Fig. 45 D) while in S. plesius and S. caliginosus sp. nov. this projection has practically the same width throughout most of its length ( Figs 10 D; 30D).

Material examined. Holotype: Male imago (light trap), BRAZIL, Pará State, Santarém, Jutuaranã stream (S 02°32'04.5"; W 54°54'33.0"; 30m) 07-08/x/2012, Nascimento, JMC col. ( INPA) . Paratypes: five female subimagos and five male subimagos (reared), two nymphs, same date as holotype, except: 03/x/2012; two male subimagos (reared). Eight nymphs: Recanto das Acácias stream (S 02°29'30"; W 54°49'55.7"; 60m) 05/x/2012, Nascimento, JMC col; nine nymphs, Floresta Nacional do Rio Tapajós, Tauari river (S 03°06'15.4"; W 55°05'20.0"; 8m) 03/x/ 2012, Nascimento, JMC col. (three male subimagos, two female imagos and seven nymphs at INPA; two male subimagos, two females and five nymphs at CZNC; two male subimagos, one female and five nymphs at IBN).

Additional material. BRAZIL: Amazonas State: Manaus : Reserva Ducke , Igarapé do Ipiranga (acampamento) (S 02°59'36.2"; W 59°53'25"; 66m), Pes AMO & Barcelos-Silva, P cols: 1 S I ♂, 1 S I ♀ . Pará State: Santarém : Córrego Cupari (S 04°10'25.8"; W 55°25'24.7"; 8m) 05/xii/2012, Nascimento JMC & Fernandes AS cols: 3 N; Igarapé Jutuaranã (S 02°32'04.5"; W 54°54'33.0"; 30m) 09/xii/2012, Nascimento JMC col: 3 N; Floresta Nacional do Tapajós , Rio Jaramaquá (S 02°49'37.7"; W 55°01'42.5"; 34m) 03/x/2012, Nascimemto JMC & Fernandes AS cols: 2 N; Alter do Chão, Igarapé Porto Novo (S 02°37'48"; W 54°58'54.6"; 36m) 01/x/2010, Nascimento JMC col: 1 N ( INPA).

Figures

FIGURE 10. Simothraulopsis plesius, male imago. A) forewing; B) hind wing; C) enlarged hind wing; D) genitalia, ventral view.

FIGURE 11. Simothraulopsis plesius, nymph. A) male, dorsal view; B) male, lateral view; C) female, dorsal view; D) gill IV; E) abdomen, ventral view.

FIGURE 12. Simothraulopsis plesius, nymph, mouthparts. A) labrum, dorsal view; B) left mandible; C) maxilla; D) hypopharynx; E) labium.

FIGURE 13. Simothraulopsis plesius, nymph. A) foreleg; B) middle leg; C) hind leg.

FIGURE 44. Simothraulopsis inaequalis sp. nov., imago. A) male, dorsal view; B) male, lateral view; C) female, dorsal view; D) male genitalia, ventral view.

FIGURE 45. Simothraulopsis inaequalis sp. nov., male imago. A) forewing; B) hind wind; C) enlarged hind wing; D) genitalia, ventral view.

FIGURE 46. Simothraulopsis inaequalis sp. nov., nymph. A) male, dorsal view; B) male, lateral view; C) female, dorsal view; D) abdomen, ventral view; E) gill IV.

FIGURE 47. Simothraulopsis inaequalis sp. nov., nymph mouthparts. A) labrum, dorsal view; B) left mandible; C) maxilla; D) hypopharynx; E) labium.

FIGURE 48. Simothraulopsis inaequalis sp. nov., nymph. A) foreleg; B) middle leg; C) hind leg.

FIGURE 49. Map of South America showing the distribution of Simothraulopsis species. Red color represents previous records. Other colors represent new records.