Ecdyonurus aurasius Dambri, Benhadji & Sartori, 2022

Dambri, Besma M., Benhadji, Nadhira, Vuataz, Laurent & Sartori, Michel, 2022, Ecdyonurus aurasius sp. nov. (Insecta, Ephemeroptera, Heptageniidae, Ecdyonurinae), a new micro-endemic mayfly species from Aures Mountains (north-eastern Algeria), ZooKeys 1121, pp. 17-37 : 17

Ecdyonurus aurasius Dambri, Benhadji & Sartori sp. nov.

Material.

Holotype. Algeria • male imago in ethanol, with its corresponding nymphal and subimaginal exuviae, Wilaya de Batna, Charchar , 35°24'22"N, 6°23'21"E, 1340 m. a.s.l., 09 Nov. 2021, B. Dambri coll. (GBIFCH01128855) [MZL] • Paratypes. 1 male imago, with its nymphal and subimaginal exuviae (GBIFCH01128846), 1 female imago, with its nymphal and subimaginal exuviae (GBIFCH01128858), [MZL]; 6 female imagos [IB-US], same data as holotype ; 1 male imago, 1 male subimago [IB-US], 2 female imagos, 7 male subimagos [FEEL-UB2], 06 Nov. 2021; 1 male imago [IB-US], 1 male imago [FEEL-UB2], 20 Oct. 2021; 1 male imago, with its nymphal and subimaginal exuviae (GBIFCH01119304), 1 female imago, with its nymphal and subimaginal exuviae (GBIFCH01128861) [MZL], 17 Oct. 2021; 1 female imago with its subimaginal exuvia, 1 female subimago (GBIFCH01128849) [MZL], 15 Oct. 2021; 1 female subimago, 1 male subimago [IB-US], 1 male subimago (GBIFCH01128853) [MZL], 2 nymphs [FEEL-UB2], 10 Oct. 2021; 3 nymphs [IB-US], 2 nymphs (GBIFCH01128857), 1 nymph on slide (GBIFCH01119301) [MZL], 09 Oct. 2021; 7 nymphs [IB-US], 15 nymphs [FEEL-UB2], 18 Jun. 2020; 15 nymphs [IB-US], 18 nymphs [FEEL-UB2], 5 nymphs (GBIFCH01128850) [MZL], 3 Mar. 2020; same locality, B. Dambri coll; 10 nymphs (GBIFCH00832138), 2 nymphs on slide (GBIFCH00673191-GBIFCH00673192) , 1 male imago (GBIFCH00673193), 1 male imago, 1 female imago, 2 female subimagos (GBIFCH00832125), 23 Jun. 2019, same locality, L. Kechemir coll. et leg. [MZL]

Other paratypes. Algeria • Wilaya de Batna, Berbaga , 35°24'01N, 6°24'31"E, 1445 m. a.s.l., 1 male imago, with its nymphal and subimaginal exuviae (GBIFCH01119302), 1 female subimago with its nymphal exuvia (GBIFCH01128848) [MZL], 5 Nov. 2021 ; 1 male imago (GBIFCH01128852), 2 nymphs (GBIFCH01128847), 1 nymph on slide (GBIFCH01119303) [MZL], 13 nymphs [IB-US], 5 nymphs [FEEL-UB2], 4 Nov. 2021; 1 male imago [IB-US], 12 nymphs [FEEL-UB2], 30 Nov. 2020; 1 nymph [IB-US], 16 nymphs [FEEL-UB2], 03 May 2020; 1 male imago [IB-US], 10 nymphs [FEEL-UB2], 02 Mar. 2020, B. Dambri coll. Algeria • Wilaya de Khenchela, Yabous , 35°21'11"N, 6°38'35"E, 1420 m. a.s.l., 2 female imagos [IB-US], 2 female subimagos, 3 nymphs [FEEL-UB2], 22 Oct. 2021 ; 1 female subimago [IB-US], 2 nymphs [FEEL-UB2], 1 female imago with its subimaginal exuvia, 1 female subimago (GBIFCH01128854) [MZL], 13-14 Oct. 2021; 1 male imago with its subimaginal exuvia GBIFCH01128851), 1 female imago with is subimaginal exuvia (GBIFCH01128845) [MZL], 12 Oct. 2021; 5 nymphs [IB-US], 1 female imago, 2 male subimagos, 6 nymphs [FEEL-UB2], 09 Oct. 2021; 4 nymphs [IB-US], 2 nymphs [FEEL-UB2], 1 nymph (GBIFCH01128859) [MZL], 20 Jul. 2020; 2 nymphs [IB-US], 19 nymphs [FEEL-UB2], 1 nymph (GBIFCH01128856) [MZL], 02 Jun. 2020; 1 female subimago with its nymphal exuvia [IB-US], 8 nymphs [FEEL-UB2], 09 May 2020; 1 female subimago [IB-US], 15 nymphs [FEEL-UB2], 08 Mar. 2020; 1 female subimago with its nymphal exuvia [IB-US], 3 nymphs [FEEL-UB2], 23 Feb. 2020, B. Dambri coll. Algeria • Wilaya de Batna, Inoughissen , 35°16'42"N, 6°32'34"E, 1670 m. a.s.l., 1 nymph (GBIFCH01128863) [MZL], 07 Jul. 2020 ; 1 nymph (GBIFCH01128865) [MZL], 18 Apr. 2020, B. Dambri coll.

Other material.

Algeria • Wilaya de Batna, oued Chaâba, 35°33'03"N, 6°00'22"E, 1262 m. a.s.l.,1 nymph [IB-US], 17 Jun. 2020 ; 3 nymphs [IB-US], 10 nymphs [FEEL-UB2], 1 nymph (GBIFCH01128860) [MZL], 20 Apr. 2020, B. Dambri coll. Algeria • Wilaya de Batna, Bouailef , 35°37'01"N, 6°11'17"E, 1060 m, 1 nymph [IB-US], 08 Mar. 2020, B. Dambri coll.

Etymology.

Aurès mountains were coined by the Berber people as Awras, meaning tawny; translated by the Romans as Aurasius mons ; Ecdyonurus aurasius is a noun in apposition.

Description.

Male imago Size: body length: 9.0-9.8 mm; forewing length 9.1-10.9 mm; cerci broken. General body color distinctly brown to reddish-brown (Fig. 3A ).

Head. Light brown, clypeal plate with blackish maculations; eyes grayish blue separated by a distance equal to the diameter of the frontal ocellus; a brownish lateral stripe present at one third of the ventral side; ocelli apically whitish-yellow, dark brown basally; antennae with scapus medium brown, flagellum grayish brown.

Thorax. Pronotum medium brown; mesonotum dorsally dark brown; ventrally with basisternum and furcasternum also dark brown, laterally with spiracles and pleura yellowish-brown. Wings. Forewings hyaline, C, Sc and R1 longitudinal veins medium brown with transverse veins fringed with brown; first transversal vein in the costal field surrounded by a dark brown maculation; others longitudinal veins dark brown, as transversal veins; pterostigmatic area milky, with 15-20 medium brown, simple and forked cross veins. Hind wings same color as forewings. Legs. Fore legs markedly darker than middle and hind ones, brown to reddish-brown; fore femora only slightly darker than tibiae and tarsi; fore legs 8.25-9.4 mm; femur:tibia:tarsi proportion: femur 2.11-2.54 mm; tibia 2.46-2.68 mm; tarsal segments 2.68-4.18 mm; T1 = 0.66-0.73 mm; T2 = 0.99-1.08 mm; T3 = 0.87-1.06 mm; T4 = 0.67-0.77 mm; T5 = 0.49-0.54 mm; gradation of tarsal segments: 2> 3>4> 1>5. Middle and hind legs yellowish-brown; dorsal face of femora washed with gray; distal part of femora and proximal part of tibiae dark brown; tarsi darker than tibiae; middle legs 5.16-5.49 mm; femur:tibia:tarsi proportions: femur 2.39-2.49 mm; tibia 1.87-1.91 mm; tarsal segments 0.9-1.09 mm; hind legs 4.97-5.71 mm; femur:tibia:tarsi proportions: femur 2.53-2.82 mm; tibia 1.65-1.93 mm; tarsal segments 0.79-0.96 mm.

Abdomen. General color brown to rusty tawny. Terga light tawny to rusty tawny. Tergum I dark brown, terga II-VII reddish-brown with two median pairs of light markings, proximal pair elongated and slightly divergent, distal pair subparallel to body axis (Fig. 4A ). Segments II-VIII with rusty-brown lateral stripes stretching from anterior to posterior margin of the segment (Fig. 3A ) and connected dorso-posteriorly (Fig. 4A ); terga VII-X slightly darker that other ones; tergum X reddish-brown, yellowish-brown posteriorly. Abdominal sterna yellowish to light brown, with two pairs of light markings, the proximal pair elongated, and divergent, distal pair rounded (Fig. 4B ). Sterna VIII-IX darker. Nervous ganglia well visible and tinted with purple on sterna II-VII. Cerci brown, with joints of segments blackish.

Genitalia. Styliger plate medium brown, lighter in the middle, strongly convex, with two small bumps near gonostyli base; first segment of gonostyli dark brown, second and third lighter (Fig. 4D ). Penis lobes yellowish-brown to brown moderately expanded laterally, outer margin rather quadratic (Fig. 4D, E ). Basal and lateral sclerites brown, darker than apical sclerite (Fig. 4E ). Lateral sclerite rather quadratic slightly larger on inner side; apical sclerite with few medium sized teeth on inner margin (Fig. 5A ); basal sclerite outer margin smooth, without teeth. Titillators straight, yellowish-brown, darker on outer margin, with two spines on the dorsal face.

Female imago. Size: body length: 9.9-13.3 mm; forewings length: 10.5-12.9 mm; cerci length: 17.9-21.3 mm. General color of body similar to that in male imago, markedly paler. Head. yellowish-brown; eyes grayish. Thorax. Prothorax yellowish gray to brown. Mesothorax dorsally pale, yellow to yellowish-brown, basisternum and furcasterum medium brown. Abdomen. Terga yellowish laterally and tawny to rusty tawny dorsally. Terga I-VIII with central longitudinal rusty tawny parallel bands and lateral stripes (Fig. 3B ). Abdominal sterna yellowish to light brown, especially VIII-IX, segments I-VII generally with two central light short strokes; nervous ganglia strongly tinted with purple on sterna II-VII. Subgenital plate large, whitish and angular, reaching two third of sternum VIII length; subanal plate acutely rounded (Fig. 4C ). Cerci brown, with joints blackish.

Female subimago. Size: body length: 12.0-12.4 mm; forewings length: 12.3 mm; cerci length: 14.0-14.8 mm. Measurements and body color similar to female imago; thorax and abdomen slightly paler. Wings dull grey.

Male subimago. Size: body length: 9.8-10.5 mm; forewings length: 10.5-11.4 mm; cerci length: 13.3-26.9 mm. Head brown to reddish-brown. Eyes grayish blue. Ocelli as in male imago. Antennae yellowish, brown basally, same than in male imago. Fore legs darker than middle and hind ones. Fore femora intensively brown distally. Middle and hind legs uniformly yellowish gray to yellow. Wings dark gray. Abdominal terga similar to male imago. Sterna slightly lighter than terga. Protuberances of styliger plate well marked, slightly yellowish, gonostyli intensively brown, yellow to whitish-yellow apically. Typical shape of penis already well apparent. Cerci brown.

Mature nymph. Size: body length: up to 7.12 mm for male and 9.6 mm for female; cerci slightly longer than body length. General body color yellowish-brown with pale yellowish markings.

Head. Mean width/length ratio 1.4-1.6, yellowish-brown to brown, with two central light spots near fore margin, and two whitish stripes along the dehiscence line (Fig. 6A ). Eyes blackish grey; ocelli whitish grey, antennae with scape and pedicel medium brown; flagellum yellowish-brown.

Mouthparts. Labrum. Mean length /labrum insertion length ratio 1.58; tips slightly turned backwards (Fig. 7A ); anterior margin with a median single row of stout setae (Fig. 7B ). Right mandible with prostheca composed of 8-11 feathered bristles; kinetodontium (inner incisor) much shorter than (outer) incisor (Fig. 7D ). Left mandible with prostheca composed of 9-11 feathered setae, kinetodontium subequal in length to incisor. Hypopharynx with lingua quadratic with dorsal margin slightly concave in the middle; superlingua well developed, with long hair-like setae on outer margin becoming shorter and less dense near apex (Fig. 7E ). Labium typical of the genus; glossae markedly rhomboid, with inner margin straight or slightly concave (Fig. 7F ). Crown of the galea-lacinia of maxilla with 16-22 comb-shaped setae; median setae with ca 15-17 teeth (Fig. 7G ). Maxillary palps 3-segmented, second segment slightly longer than third one.

Thorax. Pronotum. Mean width/length ratio 4.2-5.0, yellowish-brown to brown; lateral projections ca as long as the length of the pronotum; with lateral margin regularly convex, and tip slightly pointed (Fig. 6A ). Mesonotum medium brown with yellowish markings.

Legs. Yellowish-brown to brown; dorsal surface of femora yellowish-brown washed with grayish brown; uniformly yellowish white ventrally. Tibiae yellowish-brown. Tarsi brownish. Middle and hind legs coloration similar to fore legs. Fore femora 2.0-2.2 times longer than wide; fore tibiae subequal in length to femora. Middle femora 2.2-2.3 times longer than wide; tibiae 0.8-0.9 times femora length. Hind femora 2.3-2.4 longer than wide; tibiae 0.80-0.85 times femora length. Mid- and hind femora length 1.1-1.3 times fore-femora length. Stout setae on dorsal surface of femora similar on all legs, elongated with subparallel margins, tip truncate or slightly rounded (Fig. 8A ); claws elongated and hooked with 2-4 small denticles (Fig. 8B ).

Abdomen. Terga brownish gray; on terga II-VIII two centrally elongated yellowish spots increasing in size posteriorly and fused on tergum IX; tergum X uniformly medium brown (Fig. 6A ). Abdominal sterna yellowish white, nervous ganglia tinted with purple. Posterior margin of terga with large pointed marginal teeth alternating with medium and short ones, and several rows of microdenticles above the margin (Fig. 8C ). Posterolateral projections short, weakly sclerotized, reaching from slightly above 1/7 to 1/5 of the length of the following segment (Fig. 6C ). Gills grayish brown with distinct brown and developed tracheation; gill I tongue-shaped, gills II-VII leaf-shaped, asymmetrical, gills III-IV slightly longer than wide (Fig. 8D-J ). Cerci and paracercus yellowish-brown; each segment with a row of pointed stout setae.

Egg. Length 165-175 µm; width 120-130 µm; numerous KCT’s densely arranged at one pole (Fig. 5B ); chorionic surface covered with micro granulations.

Figures

Figure 3. Ecdyonurus aurasius sp. nov., adults in lateral view A male B female. Scale bar: 1 mm.

Figure 4. Ecdyonurus aurasius sp. nov., abdomen of adults A male in dorsal view B male in ventral view C female in ventral view D male genitalia in ventral view E male genitalia in dorsal view. Scale bar: 1 mm.

Figure 5. Ecdyonurus aurasius sp. nov. A penes in dorsal view B egg. Scale bar: 0.05 mm.

Figure 6. Ecdyonurus aurasius sp. nov., nymphal habitus A dorsal view B ventral view C posterolateral expansions of the abdomen. Scale bar: 1 mm.

Figure 7. Ecdyonurus aurasius sp. nov., nymphal mouthparts: A hemi-labrum B detail of anteromedial part of labrum in ventral view C left mandible D right mandible E left half of hypopharynx F left half of labium G comb-shaped setae at the crown of the galea-lacinia. Scale bars: 0.2 mm (A, F); 0.1 mm (B-E, G).

Figure 8. Ecdyonurus aurasius sp. nov., nymphal structures A stout setae on the dorsal surface of femora B claw C posterior margin of tergum IV D-J Gill I to VII. Scale bars: 0.05 mm (A); 0.1 mm (B-J); 0.5 mm (E-G same bar as H).