Dictyogenus muranyii Vinçon, Launay, Le Doaré, Ruffoni & Reding, sp. n.

http://lsid.speciesfile.org/urn:lsid: Plecoptera .speciesfile.org: TaxonName:506376 (Figs. 27–51)

Dictyogenus fontium – Despax, R. (1940). Bulletin de la Société d’Histoire Naturelle de Toulouse, 75:296.

Dictyogenus fontium – Vinçon, G. (1996). Bulletin de la Société Entomologique Suisse, 69:72.

Dictyogenus fontium gr sp 3-GV sensu Gilles Vinçon (early-release DNA sequence on: www.boldsystems.org, unpublished)

Materials examined. Holotype male: FRANCE, Vercors Massif, Isère department (38), Karstic Spring of Bruyant river, above Engins, Lans-en- Vercors (38250), 45° 8.798123'N, 5° 37.049358'E, 982m a.s.l., 09.06.2017, leg. G. Vinçon, deposited in the MZL (catalogue number: GBIFCH00652534) . Paratypes: same locality, same date, 3♂, 1♀, leg. G. Vinçon, deposited in the MZL (catalogue number: GBIFCH00652525, GBIFCH00652519); same locality, same date, 3L, leg. J.-P.G. Reding, deposited in the MZL (catalogue number: GBIFCH00652514) .

Additional specimens. We examined many other specimens. These are stored in the collections of Bertrand Launay (BLC), Gilles Vinçon (GVC), Jean-Paul G. Reding (RC), Dávid Murányi (MC),

Jacques Le Doaré (JLDC), Alexandre Ruffoni (ARC) and MZL.

FRANCE

Vercors Massif

Drôme department (26):

 Archiane torrent, Drôme tributary, NE Châtillon-en-Diois, Menée, Cirque d’Archiane, 44° 44.770828'N, 5° 30.214097'E, 760m, 31.07.1990, 1♂; 16.09.1990, 2♀ (leg. G. Vinçon; GVC) .

 Spring at Brudour cave, Brudour River, Bourne tributary, Bouvante (26190), 44° 55.67493'N, 5° 19.257459'E, 1182m, 13.04.2016, 3L; 02.06.2016, 2♂, 2♀, 1L, 7E (leg. B. Launay; BLC; used for molecular studies by IRSTEA, numbers B079 and B080); 21.05.2017, 1E (leg. G. Vinçon; GVC) ; 09.06.2017, 9E (leg. J.-P.G. Reding; RC) .

 Adouin river, near its spring, Vernaison and Bourne tributary, Tourtre, Saint-Martin-en- Vercors (26420), 45° 0.120928'N, 5° 27.550379'E, 793m, 21.05.2017, 1♂, 1♀ (leg. G. Vinçon, GVC) ; 09.06.2017, 11♀, 1E (leg. G. Vinçon; RC; 1♀ used for molecular studies by SwissBOL, MZL, catalogue number GBIFCH00280854); 2♂, 17♀ (leg. G. Vinçon; GVC) .

 Cholet river, Lyonne and Bourne tributary, Combe Laval, Saint-Laurent-en-Royans (26190), 44° 59.859883'N, 5° 20.75296'E, 355m, 21.05.2017, 2♂, 6E (leg. G. Vinçon; GVC) .

Isère department (38):

 Bruyant river, Furon and Isère tributary, above Engins, Lans-en-Vercors (38250), 45° 8.798123'N, 5° 37.049358'E, 982m, 06.10.1991, 1E; 25.06.1995, 7♂, 4♀; 10.05.1998, 1♂; 10.06.2007, 1♂; 22.06.2008, 1♂; 22.06.2009, 32♂, 6♀ (1♂ used for molecular studies by A. Reding) ; 07.07.2012, 7♂, 2♀, 1L (leg. G. Vinçon; GVC); 07.06.2015, 3♂, 2♀, 6L, 5E (leg. B. Launay; BLC); 09.06.2017, 2♂, 1♀, 17E (leg. G. Vinçon; GVC); 7♂, 1♀, 7L, 3E (leg. J.-P.G. Reding; RC; 1♂ used for molecular studies by SwissBOL, MZL, catalogue number GBIFCH00280811) .

 Cuves de Sassenage strong rheocrene spring, Germe brook, Furon and Isère tributary, Sassenage (38474), 45° 12.516243'N, 5° 39.078175'E, 330m, 15.06.1991, 1♂, 2♀ strongly brachypterous (leg. G. Vinçon; MC) .

 Drevenne river, Isère tributary, Pont Chabert, Saint-Gervais (38470), 45° 10.643943'N, 5° 29.885486'E, 885m, 15.06.1991, 1L (leg. G. Vinçon; GVC); 31.05.2012, 2♂; 17.07.2012, 2L; 11.07.2015, 3L (leg. J. Le Doaré; JLDC); 06.06.2015, 1E (leg. B. Launay; BLC) .

 Font Noire river, Bourne tributary, Villard-de- Lans (38250), 45° 4.472474'N, 5° 33.970966'E, 1010m, 01.06.2016, 1♂, 1E (leg. B. Launay; BLC; used for molecular studies by IRSTEA, number B120) .

 Fauge river, Bourne tributary, Villard-de-Lans (38250), 45° 3.373805'N, 5° 34.664105'E, 1230m, 01.06.2016, 1E (leg. B. Launay; BLC) .

 Spring of Furon river, Lans-en-Vercors (38250), 45° 6.304551'N, 5° 36.221224'E, 1294m, 12.07.2015, 6L (leg. J. Le Doaré; JLDC) .

Chartreuse Massif

Isère (38) and Savoie (73) departments:

 Sarcenas river at Sarcenas, Isère tributary, (38700), 45° 16.829887'N, 5° 45.251584'E, 1093m, 20.04.1986, 5L; 01.06.1986, 4L; 05.10.1986, 1♂ (leg. G. Vinçon; GVC) .

 Spring of Guiers-Vif river, Rhône tributary, Cirque de Saint-Même, Saint-Pierre-D’Entremont (73670), 45° 23.491629'N, 5° 53.464859'E, 1050m, 21.06.1992, 3♀; 12.09.1992, 4♀, 1E; 21.06.1992, 3♀ (leg. G. Vinçon; GVC) .

 Karstic spring of Guiers Mort, Rhône tributary, Saint-Pierre-de-Chartreuse (38380), 45° 19.571976'N, 5° 51.452039'E, 1360m, 11.09.1938, stage and numbers not specified (leg. Ms. Daudin, fide Despax 1940).

Diagnosis. General color dark brown with tawny and yellow spots (Figs. 27, 28). Males and females macropterous; only two females were found strongly brachypterous. Apex of the frontal sclerite of the epiproct of adult males very slightly turned downwards, in lateral view (Fig. 33). Female subgenital plate covering half of the abdominal sternum 9 (Fig. 36). Body length of males 17.2 to 20.9 mm; females 18 to 23.6 mm. Anterior wings of males 15 to 19.3 mm; females 17.7 to 21.5 mm. Posterior wings of males 12.5 to 15.8 mm; females 15.3 to 17.4 mm.

Adults (Figs. 27–36). Upper side of the head brown, with large yellow spots (Fig. 28). M-line yellow, not interrupted in its middle (Fig. 28). Between the lateral ocelli, a large, ovoid, yellow area delimitated posteriorly by the epicranial suture (Fig. 28). Presence of a large, yellow, median band extending from the anterior margin of the pronotum to its posterior margin (Fig. 28). Band slightly constricted in the middle and then steadily widening toward the posterior margin (Fig. 28). A tawny area on each side of the pronotum, with dark, sculpted rugosities (Fig. 28). Anterior and posterior angles of pronotum almost rectangular (Fig. 28). Abdominal sterna 1 to 6 pale yellow, with two dark patches. Antennae dark brown; cerci light brown with basal part pale yellow (Figs. 29, 30). Wing venation as typical for the genus (Fig. 31; cf. Fig. 8). Forewing with the two cross-veins “ra- rp” and “rp- ma”

nearly aligned (like in Fig. 8). Numerous crossveins forming a reticulated area between RA and RP (Fig. 31; cf. Fig. 8). Cross-vein “ra- rp” and subcostal area faintly infuscate (as in Fig. 8).

Male terminalia (Figs. 29, 30, 32–35). Epiproct flanked by flat and spatulate lateral stylets (Figs. 33, 34). Abdominal tergum 10 divided into hemiterga whose lobes are covered with a bunch of 20 to 25 long setae in which 3 to 6 stronger and longer spines (half of the length of the hemitergal lobes) are embedded (Figs. 29, 32). Hemitergal lobes bulb-shaped with a slight distal knob (Fig. 30), both pointing rearwards (Fig. 30) and almost horizontally toward each other (Figs. 29, 32). Apex of frontal sclerite of epiproct slightly turned downwards, in lateral view (Fig. 33). Lateral stylets long, only slightly enlarged at apex, in lateral view (Figs. 33, 34). Abdominal sternum 7 composed of multiple plates (as in Figs. 7, 59, 82).

Females (Fig. 36). Females not formally identifiable to species level. Female subgenital plate (Fig. 36) covering at most half of sternum 9. Its general shape is semi-circular with a shallow Vshaped median notch.

Mature larvae (Figs. 37–45). Interocellar area with a narrow yellow patch nearly reaching lateral ocelli (Figs. 37–39). Lateral ocelli with small lateral circum-ocellar yellow patch (Fig. 38). A large, elliptical yellow patch above each lateral ocellus (Figs. 37–39). M-line well visible only in its medial, crescent-shaped, section (Figs. 37–39). Pronotum wider than long (Figs. 38, 39). Medio-dorsal setae on pronotum long, but not compacted, sometimes covering only the posterior half of the pronotum (Figs. 40, 41). Medio-dorsal row of setae present on mesonotum and metanotum (Fig. 40). Abdominal terga with a row of short and sparse medio-dorsal setae (Fig. 42). Paragenital plates, in ventral view, without spines, or with only 1 spine on one of the paragenital plates, but with numerous empty spine insertion points (Fig. 44). Medio-dorsal row of swimming-hairs of caudal setae sparse, slightly longer than the diameter of the cerci (Fig. 43). General aspect as in Fig. 37.

Egg characteristics (Figs. 46–51). General shape triangular or trilateral in cross section. Posterior pole of egg regularly rounded; ridges protruding (Figs. 46, 47). Chorionic surface spring of Brudour, Drôme dpt, France. Photo B. Launay. 43. Medio-dorsal setae on cerci. Karstic spring of Brudour, Drôme dpt, France. Photo A. Ruffoni. 44. Paragenital plates, ventral view. Karstic spring of Brudour, Drôme dpt, France. Photo B. Launay. 45. Stipe. Karstic spring of Brudour, Drôme dpt, France. Photo B. Launay.

with polygonal follicle cell impressions (Figs. 48, 50, 51). Anchor papillate, donut shaped apically with central depression (Figs. 48, 49). Micropyles not protruding and arranged regularly in a line in the middle of the egg (Figs. 47, 50). Eclosion line absent (Figs. 46, 47).

Comparison to Congeners.

Adults. In the adult male of Dictyogenus muranyii sp. n., a wide, V-shaped membranous area between the hemitergal lobe and the inner anterior corner of the hemitergum is present (Figs. 29, 32), whereas this area is sclerotized and much narrower in D. alpinum (Fig. 56). The lateral stylets in D. muranyii sp. n. are slightly enlarged apically (Figs. 33, 34), intermediate in form between those of D. alpinum (Fig. 57) and those of the D. fontium species complex (Fig. 80). In the adult female of D. muranyii sp. n., the subgenital plate (Fig. 36) covers at most the upper half of sternum 9, as is also the case for specimens of the D. fontium species complex (Figs. 83, 84), whereas the subgenital plate of D. alpinum covers ¾ of sternum 9 (Figs. 60, 61). The anterior and posterior angles of the pronotum of Dictyogenus muranyii sp. n., D. jurassicum sp. n. and D. fontium are almost rectangular (Figs. 2, 28, 79), whereas those of D. alpinum are rounded (Fig. 54). Adult males and females of Dictyogenus muranyii sp. n. hence have more affinities with those of the D. fontium species complex than with those of D. alpinum .

Mature larvae. Dictyogenus muranyii sp. n. differs from D. fontium by the presence of medio-dorsal setae on the pronotum (Fig. 41 compared to Fig. 86). Medio-dorsal setae on pronotum are long and sparse in D. muranyii sp. n. (Figs. 40, 41), whereas they are long and dense in D. alpinum (Fig. 71), and short and scattered, arranged as two loosely demarcated rows in D. jurassicum sp. n. (Fig. 13).

Distribution and ecology. Dictyogenus muranyii sp. n. inhabits karstic springs (some of them intermittent; Fig. 52) in the French Vercors and Chartreuse massifs (Fig. 92). The localities occurring on the south western part of the Vercors Massif belong to the Drôme watershed (main Rhône tributary); those occurring on the northern and eastern part of the Vercors Massif, and on the southern part of the Chartreuse Massif belong to the Isère watershed (main Rhône tributary), and those occurring on the western

part of the Chartreuse Massif belong to the Guiers watershed (Rhône tributary). The life cycle of Dictyogenus muranyii sp. n. is probably similar to the one of D. jurassicum sp. n. The main emergence period of adults is in May and June, although isolated specimens occur until September. We have noted on one occasion a spectacular upstream flight of females in mid-June on the river Adouin (Fig. 53). Some of the females were ovipositing under large stones right at the spring head. Mature larvae emerge preferentially on small islets located in the middle of the river.

Etymology of Dictyogenus muranyii sp. n. This species is dedicated to Dr. Dávid Murányi, Hungarian Natural History Museum, Budapest, Hungary, in recognition of his outstanding contributions to the plecopteran taxonomy.