Oligoneuriopsis skhounate Dakki & Giudicelli, 1980

Barber-James, Helen M., Zrelli, Sonia, Yanai, Zohar & Sartori, Michel, 2020, A reassessment of the genus Oligoneuriopsis Crass, 1947 (Ephemeroptera, Oligoneuriidae, Oligoneuriellini), ZooKeys 985, pp. 15-47 : 15

Oligoneuriopsis skhounate Dakki & Giudicelli, 1980 Figures 9A , 10A , 11A-C , 12A , 14E , 15E

Oligoneuriopsis skhounate Dakki & Giudicelli, 1980: 19, figs 14-29 (male imago, nymph).

Material examined.

Algeria • 1N (sequenced GBIFCH00763571); Oued Cherf, Medjez Amar; 36.44306°N, 7.31083°E; alt. 205 m a.s.l.; 3 Oct. 2018; B. Samraoui leg.; MZL • 2N (sequenced GBIFCH00763569-GBIFCH00763570); Oued Cherf, Dbabcha; 36.2166°N, 7.3181°E; alt. 610 m a.s.l.; 18 Oct. 2019; B. Samraoui leg.; MZL • Morocco • 3N; Marrakech, Palmeraie, Oued Tensift; 31.6619°N, 7.9694°W (estimated); alt. 443 m a.s.l.; 27 Apr. 1960; J. Aubert leg.; MZL • Spain • 4N; Pyrénées, Barbastro (Huesca), Rio Vero; 42.2400°N, 0.1278°W (estimated); alt. 1000 m a.s.l.; 24 Jun. 1956; H. Bertrand leg.; MZL • 1N; Sierra Morena, Venta de Cardenas; 38.4006°N, 3.5119°W (estimated); alt. 650 m a.s.l.; 2 Aug. 1960; J. Aubert leg.; MZL • 3N; Valladolid, Cabezon, Rio Pisuerga; 41.4650°N, 5.2297°W (estimated); alt. 650 m a.s.l.; 17 Aug. 1988; D. Studemann & P. Landolt leg.; MZL • 41N; Malaga, Cortes de la Frontera, Rio Guadairo; 36.5483°N, 5.3675°W (estimated); alt. 250 m a.s.l.; 21 Aug. 1988; D. Studemann & P. Landolt leg.; MZL • 4N, 10s♀, 17♂; same locality; 15 Sep. 1988; P. Landolt leg.; MZL • Tunisia • 1N; Bizerte, Mateur, Oued Joumine, upstream Lake Ichkeul dam; 36.9628°N, 9.5244°E; alt. 105 m a.s.l.; 20 Nov. 2004; S. Zrelli leg.; LBE • 22N, 1s♀; same locality; 26 Jun. 2005; S. Zrelli leg.; LBE • 20N, 2s♀; same locality; 18 Jul. 2005; S. Zrelli leg.; LBE • 40N; same locality; 28 Aug. 2005; S. Zrelli leg.; LBE • 40N; same locality; 6 Sep. 2005; S. Zrelli leg.; 39 LBE, 1 MZL • 40N; same locality; 24 Oct. 2005; S. Zrelli leg.; LBE • 35N; same locality; 26 Jun. 2006; S. Zrelli leg.; 24 LBE, 11 MZL • 11N; same locality; 31 Jul. 2006; S. Zrelli leg.; LBE • 2N, 1s♀; same locality; 6 Apr. 2009; S. Zrelli leg.; MZL • 2N; same locality; 17 May 2010; S. Zrelli leg.; LBE • 5N; Tabarka, Oued Bouterfes; 36.953°N, 8.9125°E; alt. 100 m a.s.l.; 4 Jan. 2005; S. Zrelli leg.; LBE • 6N; Jandouba, Fernana, Oued Ellil; 36.7203°N, 8.7339°E; alt. 237 m a.s.l.; 28 Jul. 2005; S. Zrelli leg.; LBE • 2N; same locality; 12 Sep. 2005; S. Zrelli leg.; LBE • 4N; same locality; 29 Jul. 2006; S. Zrelli leg.; LBE • 9N; same locality; 30 Aug. 2006; S. Zrelli leg.; LBE • 10N; same locality; 26 Jun. 2008; S. Zrelli leg.; LBE • 7N; Oued Ghezala; 36.6431°N, 8.6986°E; alt. 229 m a.s.l.; 30 Aug. 2006; S. Zrelli; LBE • 5N; same locality; 21 Nov. 2009; S. Zrelli; LBE.

Male imago.

Adequately described and illustrated by Dakki and Giudicelli (1980). The most important character is on the genitalia where the shape of the lateral longitudinal lobe of the penis ends in a rounded sclerite a little bit larger than the lateral lobe (Fig. 9A ).

Nymph

(Fig. 10A ). Adequately described and illustrated by Dakki and Giudicelli (1980), with the following complements: setae on the outer margin of hind femora well developed and reaching the apex; outer margin of hind tibiae covered by a dense row of long and thin setae; lamella of gill I minute, fibrillae much longer than the lamella length; setae on distal inner margin of gills II-VII short and thin; posteromedially sternal patch of long setae present on segments (II)III-V, most developed on segments III-IV.

Eggs.

General shape rhomboid, ca. 280 µm long and 250 µm wide, (Fig. 11A ) chorionic surface rather smooth, micropyle tagenoform, smooth, sperm guide well apparent (Fig. 11B ), KCT’s rather regularly arranged, ca. 10 µm of diameter, formed by coil-thread ending in a leaf-like and flat structure (Fig. 11C ).

Affinities.

At the male adult stage, O. skhounate is distinguished from O. lawrencei by the presence of crossveins in the proximal part of the subcostal area, and from O. lawrencei and O. dobbsi by the shape of the apex of the lateral longitudinal lobe of penis sclerite which is only slightly enlarged. In the nymphal stage, O. skhounate differs from O. jessicae by the absence of abdominal carina and from O. lawrencei and O. elisabethae by the setation of the dorsal margin of hind femora with much longer setae; it also differs from O. dobbsi by the size of gill I lamella, much longer in the latter.

The ecology of the nymph in North Africa is described by Bouhala et al. (2020).

Known distribution.

Algeria, Morocco, Spain, Tunisia.

Figures

Figure 9. Genitalia of Oligoneuriopsis in ventral view A O. skhounate B O. orontensis. Black arrows: Apex of the lateral longitudinal lobe of penis. White arrows: Proximal process of penis. Scale bar: 1 mm.

Figure 10. Habitus of Oligoneuriopsis nymphs in dorsal view A O. skhounate B O. orontensis. Scale bar: 5 mm.

Figure 11. O. skhounate (A-C) and O. orontensis (D-F) A, D shape of the egg B, E micropyle C, F KCT's.

Figure 12. Hind legs of Oligoneuriopsis in dorsal view, showing femoral and tibial setation A O. skhounate B O. orontensis. Scale bar: 1 mm.

Figure 14. Hind femora of representative Oligoneuriella (A-C) and Oligoneuriopsis (D-F) species A Oligoneuriella rhenana B Oligoneuriella pallida C Oligoneuriella skoura D Oligoneuriopsis lawrencei E Oligoneuriopsis skhounate F Oligoneuriopsis orontensis.

Figure 15. Outline of gill plate III of representative Oligoneuriella (A-C) and Oligoneuriopsis (D-F) species A Oligoneuriella rhenana B Oligoneuriella pallida C Oligoneuriella skoura D Oligoneuriopsis lawrencei E Oligoneuriopsis skhounate F Oligoneuriopsis villosus.