Protonemura jurassica Reding, Bolard & Vinçon, 2017

Reding, Jean-Paul G., Bolard, Audrey & Vinçon, Gilles, 2017, A new species of Protonemura Kempny, 1898 (Plecoptera: Nemouridae) from the French and Swiss Jura Mountains, Zootaxa 4276 (4), pp. 554-568 : 555-567

Protonemura jurassica Reding, Bolard & Vinçon sp. n.

( Figs. 1 –16)

Protonemura brevistyla ( Ris, 1902) pro parte

Morphological diagnosis. A medium-sized Protonemura species. Males and females macropterous. Body length of males 5 to 6 mm, females 7 to 8 mm. Cervical gills medium-sized, with one slight pre-apical constriction of the two central gills. Sclerotized stem of the median lobe of the paraprocts of adult males ( Figs. 1 , 2 and 3) ciliated on both sides and much longer and slender than that of P. brevistyla , whose name aptly refers to this aspect (Figs. 17 and 19; Ris 1902: 432, fig. 3). Paraprocts of adult females acuminated at apex (Fig. 7).

Type material. Holotype male: FRANCE: Jura Mountains, Doubs Department, Karstic spring of Loue River , Ouhans (25), 47° 0.645115' N, 6° 17.97486' E, 529 m a.s.l., 21.03.2013, leg. Audrey Bolard, deposited in the MZL (catalogue number: GBIFCH00284217).

Paratypes: same locality, same date, 4m, 4f, leg. A. Bolard, deposited in the MZL (catalogue number: GBIFCH00284216).

Additional specimens are stored in the collections of Jean-Paul G. Reding (RC), Gilles Vinçon (GVC), Audrey Bolard (BC) and the Museum of Zoology, Lausanne ( MZL).

L=mature larvae or nymphs; m=adult male; f=adult female

1. SWITZERLAND, Jura Mountains, Chasseron Region, Areuse River Basin, Canton of Neuchâtel, Rhine

tributaries:

1.1 Karstic spring of Fleurier Brook, Raisse, 46° 53.467116' N, 6° 34.650005' E, 760 m 0 7.09.1996, 1m; 0 6.08.2010, 1f (voucher specimen; two legs used for molecular studies); 0 3.08.2011, 22L; 12.08.2011, 5L; 0 7.07.2016, 12L (leg. J.-P. G. Reding; RC; 6L deposited in the MZL, catalogue number: GBIFCH00284225)

27.9.2001, 1m, 30f (leg. P. Stucki; MZL)

1.2 Karstic spring of Areuse River, La Doux, Saint-Sulpice, 46° 54.696' N, 6° 32.926' E, 805 m 0 8.07.1984, 1m (leg. W. Matthey; RC)

18.07.1997, 1m; 26.07.1998, 1f; 0 6.07.2004, 1m (voucher specimen; two legs used for molecular studies); 23.07.2010, 1f; 0 6.08.2010, 4m, 1f (leg. J.-P. G. Reding; RC; 2m, 1f deposited in the MZL, catalogue number: GBIFCH00284218)

2. SWITZERLAND, Jura Mountains, Lake of Neuchâtel region , Canton of Vaud, Rhine tributaries: 2.1 Karstic spring of La Raisse , near Concise , 46° 51.786533' N, 6° 45.046069' E, 430 m 29.9.2001, 1f (leg. P. Stucki; MZL)

3. SWITZERLAND, Jura Mountains, Canton of Jura, Doubs drainage basin, Rhône tributaries: 3.1 Karstic spring of Côte au Bouvier , near Soubey , 47° 18.065225' N, 7° 18.065225' E, 570 m 28.05.2013, 1f (leg. J.- P. G. Reding; RC)

4. SWITZERLAND, Jura Mountains, Canton of Bern, Suze Drainage Basin , Rhine tributaries: 4.1 Karstic spring of La Dou , near Cormoret , 47° 10.084454' N, 7° 2.474492' E, 739 m 21.04.2016, 2L; 20.04.2017, 2m, 3f, 1L (leg. J.- P. G. Reding; RC)

5. FRANCE, Jura Mountains, Doubs Department, Doubs drainage basin, Rhône tributaries:

5.1 Karstic spring of Doubs River, Mouthe (25), 46° 42.295' N, 6° 12.545' E, 945 m 18.07.1991, 2m (leg. J. Aubert; GVC)

14.07.1996, 11m, 14f; 22.07.1996, 4m, 5f; 27.08.1996, 12m, 15f; 15.10.1996, 1m, 4f; 0 4.05.2009, 8m, 1f (leg. G. Vinçon; GVC)

14.07.1996, 3m; 21.09.2009, 2m, 1f; 20.07.2010, 1f; 19.05.2016, 4m; 10.06.2016, 1L (leg. J.-P. G. Reding; RC)

5.2 Karstic spring of Dessoubre River, Consolation-Maisonnettes (25), 47° 9.181275' N, 6° 36.051564' E, 623 m 30.08.1996, 2f (leg. G. Vinçon; GVC)

5.3 Karstic spring of Le Val River, Pierrefontaine-les-Varans (25), 47° 12.730003' N, 6° 33.163793' E, 669 m 30.08.1996, 2f (leg. G. Vinçon; GVC)

5.4 Karstic spring of Cusançin River, Cusance (25), 47° 19.312213' N, 6° 26.254235' E, 333 m 21.07.2010, 1f (leg. J.- P. G. Reding; RC)

6. FRANCE, Jura Mountains, Doubs and Jura Department, Loue Drainage Basin, Rhône tributaries:

6.1 Karstic spring of Loue River, Ouhans (25), 47° 0.645115' N, 6° 17.97486' E, 529 m 10.09.2012, 3m, 1f, 13L; 22.10.2012, 1m (leg. A. Bolard; RC)

21.03.2013, 23m, 12f (2m, 1f deposited in the MZL, catalogue number: GBIFCH00284224); 16.04.2013, 6m, 5f; 0 2.05.2013, 3m, 4f; 22.05.2013, 3m; 30.09.2013, 1m, 6f; 25.10.2013, 1m (leg. A. Bolard; BC) 10.04.2013, 2m, 3f (leg. J.-P. G. Reding; RC)

6.2 Karstic spring of Moulin Miguet, Ouhans (25), 47° 1.326046' N, 6° 17.934465' E, 456 m 0 1.04.2014, 1L; 14.05.2013, 1L (leg. J.-P. G. Reding; RC)

6.3 Karstic spring of Lison River, near Nans-sous-Sainte-Anne (25), 46° 57.909686' N, 6° 0.68981' E, 432 m 22.05.2013, 1m, 2f (leg. A. Bolard; BC)

21.06.2016, 1f (leg. J.-P. G. Reding; RC)

6.4 Karstic spring of Furieuse River, La Doye (39), 46° 52.785549' N, 5° 54.197315' E, 572 m Verneaux 1973, sub nom. Protonemura brevistyla , not confirmed.

Description of Protonemura jurassica sp. n. Males ( Figs. 1 –6). Tergites 6, 7 and 8 with a row of spines on the central posterior margins (Fig. 6). Hypoproct bearing at its base a long and narrow vesicle with nearly parallel edges (Fig. 3). Inner lobe of paraprocts hidden by hypoproct. Median lobe with sclerotized base; the rest membranous ( Figs. 1 and 2). Upper part of sclerotized base of median lobe large, with two branches, the one on the dorsal side ending in a narrow tip and the one on the ventral side in a blunt tip ( Figs. 1 and 2). Sclerotized stem arising from the base of the median lobe very long, nearly reaching the apex of the membranous part of the outer lobe ( Figs. 1 , 2 and 3). Sclerotized stem slender, ciliated on both sides and ending in a single, long, thorn ( Figs. 1 , 2 and 3). Outer lobe of paraprocts with a well-developed membranous field flanked by a heavily sclerotized area ( Figs. 1 and 2). Sclerotized part nearly straight, with an outward pointing hammer-like extension at its apex and a smaller knob in its middle (Fig. 2). Apical extension of outer lobe with three to six spines pointing inwards ( Figs. 1 and 2). Epiproct long and slender in lateral view, hardly enlarged in the apical portion (Figs. 4 and 5). Lateral sclerites of epiproct thin (Fig. 5). Ventral sclerite of epiproct supporting a nearly triangular-shaped projection with a few short spines (Fig. 5). Apex of epiproct concave in lateral view (Fig. 5). Cerci well developed, voluminous and rounded, slightly shorter than the paraprocts ( Figs. 1 , 2 and 3). In males and females, head without contrasting colours, uniformly dark in mature specimens and reddish brown in freshly emerged specimens. Femur of hind legs distally with a dark band in both sexes.

Females (Figs. 7 and 8). Pregenital plate of sternite 7 with a small median sclerotized area, that extends only marginally over sternite 8 (Figs. 7 and 8). Subgenital plate with a nearly rectilinear central posterior margin (Figs. 7 and 8). Lobes of the subgenital plate protruding and rounded at their lateral margins (Fig. 8). The two lobes of the subgenital plate nearly parallel and separated by a deep median depression (Figs. 7 and 8). Vaginal lobes on each side of the subgenital plate large and well visible (Figs. 7 and 8). Paraprocts medium-sized and pointed at apex (Fig. 7).

Mature larvae and nymphs ( Figs. 9 –16). General colour brown. Cervical gills of medium length, with a slight pre-apical constriction of the two central gills ( Fig. 9). Dorso-lateral pair of bristles on tergites short ( Figs. 10 and 11 ), generally present only on tergites 1 to 7 ( Fig. 10). Tergites and sternites of first six abdominal segments separated by a small membranous area ( Fig. 11 ). Paraprocts of male larvae flattened at apex ( Figs. 11 and 12). Sternite 9 of male larvae triangular-shaped with a rounded tip (Fig. 13). Paraprocts of female larvae mid-sized, narrowing towards apex (Fig. 14). Subgenital plate of female larvae shaped as two small symmetrically arranged triangles with stretched tip at outer base (Fig. 15). Head dark or reddish brown, with no areas contrasting in colour (Fig. 16).

Morphological affinities. Protonemura jurassica is morphologically similar to P. lateralis ( Pictet, 1836) and P. brevistyla (widely distributed in the Alps, Prealps and Carpathians), P. zhiltzovae Vinçon & Ravizza, 2005 (endemic to the Pyrenees), P. austriaca Theischinger, 1976 (eastern Austria and Germany) and P. julia Nicolai, 1983 (Julian Alps, Carinthia, Karawanken ( Graf & Hutter 2002), Slovenia and Croatia (Popijač & Sivec 2009)). Since the latter three species are unlikely to occur in the Jura Mountains, we provide a differential diagnosis only for P. lateralis , P. brevistyla and P. jurassica .

Adult males. Protonemura jurassica and P. brevistyla . Ventral vesicle on the hypoproct of P. jurassica long and narrow, with nearly parallel edges (Fig. 3), whereas it is shorter and wider, apically with an outward bulge, in P. brevistyla (Fig. 17). Median lobe of the paraprocts of P. jurassica with a long and slender sclerotized stem ( Figs. 1 , 2 and 3), whereas this stem is much shorter and thicker in P. brevistyla (Figs. 17, 19 and 20; Ris 1902: 432, fig. 3; Aubert 1959: 38, fig. 75). Sclerotized part of outer lobe of the paraprocts of P. jurassica with a marked lateral extension at its apex ( Figs. 1 and 2), whereas there is no such extension in P. brevistyla (Figs. 18 and 19). Apex of the epiproct medially with a slight concave curvature in P. jurassica (Figs. 4 and 5), whereas that of P. brevistyla is nearly straight (Fig. 20; Vinçon & Ravizza 2005, fig. 5o).

Protonemura jurassica and P. lateralis . In males and females, head below the ocelli light reddish brown, dark above, with a well-marked separation line in Protonemura lateralis (Fig. 23), whereas the head is uniformly dark or red brown in P. jurassica . Ventral vesicle on the hypoproct of P. jurassica long and narrow, with nearly parallel edges (Fig. 3), whereas it is shorter and wider, apically with an outward bulge, in P. lateralis ( Fig. 24 ). Sclerotized base of median lobe large, with two branches, in P. jurassica ( Figs. 1 and 2), whereas this base is narrow in P. lateralis (Fig. 26; Vinçon & Ravizza 2005, Fig. 6f). Sclerotized part of outer lobe of the paraprocts of P. jurassica with a marked lateral extension at its apex ( Figs. 1 and 2), whereas this extension is situated below the apex in P. lateralis (Figs. 25 and 26; Vinçon & Ravizza 2005, fig. 6f). Sclerotized stem arising from the base of the median lobe ciliated in P. jurassica ( Figs. 1 , 2 and 3), whereas there is no ciliation on the stem of P. lateralis (Figs. 25 and 26; Vinçon & Ravizza 2005, fig. 6f). Apex of the epiproct medially with a slight concave curvature in P. jurassica (Figs. 4 and 5), whereas the apex of the epiproct of P. lateralis is narrow and acute (Fig. 25; Vinçon & Ravizza 2005, fig. 6g). Ventral sclerite of epiproct of P. jurassica with a nearly triangular-shaped projection (Figs. 4 and 5), whereas there is no such projection in P. lateralis (Fig. 25).

Adult females. Protonemura jurassica and P. brevistyla . Paraprocts of medium-length and slightly pointed at apex in P. jurassica (Fig. 7), whereas they are blunt and short in P. brevistyla ( Fig. 21). Subgenital plate with a nearly rectilinear central posterior margin in P. jurassica (Figs. 7 and 8), but it is regularly rounded in P. brevistyla ( Fig. 21; Vinçon & Ravizza 2005, fig. 5p). The two lobes of the subgenital plate are nearly parallel in P. jurassica (Figs. 7 and 8), are diverging in P. brevistyla ( Fig. 21).

Protonemura jurassica and P. lateralis . Lobes of the subgenital plate in P. jurassica parallel with a small but deep median notch (Figs. 7 and 8), whereas they are oblique with a shallow and large median depression in P. lateralis (Fig. 27). In P. jurassica , the pregenital plate of sternite 7 with a small median sclerotized area (Figs. 7 and 8) whereas this area is much larger in P. lateralis (Fig. 27). The paraprocts are characteristically pointed and angular in P. lateralis (Fig. 27), but only slightly pointed in P. jurassica (Fig. 7). Cervical gills short without apical constriction in P. lateralis , whereas they are of medium length and with a slight apical constriction in P. jurassica . Vaginal lobes large and well visible in P. jurassica (Figs. 7 and 8), whereas they are small in P. lateralis (Fig. 27; Vinçon & Ravizza 2005, fig. 6h).

Female specimens of Protonemura jurassica emerging early in spring might also be confused with P. praecox (Morton, 1894) . The vaginal lobes of P. praecox ( Vinçon & Ravizza 2005, fig. 4d) are much longer and more slender than those of P. jurassica (Figs. 7 and 8). The subgenital plate of P. praecox ( Vinçon & Ravizza 2005, fig. 4d) is also much smaller and narrower than that of P. jurassica (Figs. 7 and 8).

Distribution and ecology. Protonemura jurassica is restricted to karstic springs ( Figs. 28 , 29 and 30 ) and their immediate vicinity in the Jura Mountains of France and Switzerland ( Fig. 31 ), between 333 m and 945 m. The flight period of P. jurassica extends from spring to autumn. Adults of both sexes emerge from the end of March until the end of October with a pause during June. The life-cycle is similar to the seasonal univoltine wintersummer type of many Ephemeroptera (Us–Uw, sensu Clifford 1982): one cohort of P. jurassica overwinters as larvae and emerges early in spring, whereas the other cohort overwinters in the egg stage, to emerge later in summer and in autumn. In contrast, P. brevistyla emerges at the end of summer and in autumn ( Aubert 1959; Vinçon & Ravizza 2005; Lubini et al. 2012b), and only very rarely in spring ( Aubert 1949: 353).

Etymology of Protonemura jurassica . This species is named after the region in which it occurs, namely the Jura Mountains of France and Switzerland.

Figures

FIGURE 1. Protonemura jurassica sp. n., male terminalia, lateral view. FIGURE 2. Protonemura jurassica sp. n., male terminalia, lateral view. FIGURE 3. Protonemura jurassica sp. n., male terminalia, dorsal view. FIGURE 4. Protonemura jurassica sp. n., male epiproct, lateral view.

FIGURE 11. Protonemura jurassica sp. n., larva, lateral view.

FIGURE 24. Protonemura lateralis, male, ventral view.

FIGURE 28. The karstic spring of the river Lison, Nans-sous-Sainte-Anne, Doubs department (25), France.

FIGURE 29. The karstic spring of the river Doubs, Mouthe, Doubs department (25), France.

FIGURE 30. The karstic spring of the river Loue, Ouhans, Doubs department (25), France.

FIGURE 31. Distribution map of Protonemura jurassica sp. n. Compiled by A. Bolard.