Dictyogenus jurassicum Reding, Launay, Le Doaré, Ruffoni & Vinçon, 2019

Reding, Jean-Paul G., Launay, Bertrand, Doaré, Jacques Le, Ruffoni, Alexandre & Vinçon, Gilles, 2019, Two New Species Of Dictyogenus Klapálek, 1904 (Plecoptera: Perlodidae) From The Jura Mountains Of France And Switzerland, And From The French Vercors And Chartreuse Massifs, Illiesia 15 (2), pp. 27-64 : 31-40

publication ID

https://doi.org/10.5281/zenodo.4761285

publication LSID

lsid:zoobank.org:pub:C9602772-1A3A-4C43-AA2D-534DF8D79AEB

DOI

https://doi.org/10.5281/zenodo.4764635

persistent identifier

https://treatment.plazi.org/id/352C87AB-0064-FFC4-F595-F8F85B147BB1

treatment provided by

Felipe

scientific name

Dictyogenus jurassicum Reding, Launay, Le Doaré, Ruffoni & Vinçon
status

sp. n.

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

http://lsid.speciesfile.org/urn:lsid: Plecoptera   .speciesfile.org:

TaxonName:506375 ( Figs. 1–25 View Fig View Figs View Figs View Figs View Fig View Fig View Fig View Figs View Figs )

Dictyogenus (Besdolus) ventralis   – Verneaux, J. (1973). Annales scientifiques de l’Université de Besançon, Zoologie, Physiologie et Biologie Animale, 3ème Série, 9:98.

Dictyogenus fontium   – Reding, J.-P.G. (1998). Bulletin romand d’entomologie, 16:42.

Dictyogenus alpinum   – Verneaux et al. (2003). Hydrobiologia, 490:71.

Dictyogenus fontium   gr sp 5-GV sensu Gilles Vinçon (early-release DNA sequence on: www.boldsystems.org, unpublished)

Materials examined. Holotype male: SWITZERLAND, Jura Mountains , Doubs Valley , canton of Jura , Karstic spring of Côte au Bouvier , near Soubey, 47° 18.028074'N, 7° 3.595063'E, 570m a.s.l., 05.05.2009, leg. Gilles Vinçon, deposited in the MZL (catalogue number: GBIFCH00652518 ). GoogleMaps   Paratypes: same locality, 16.06.2009, 2♂, 2♀, leg. G. Vinçon, deposited in the MZL (catalogue number: GBIFCH00652530 , GBIFCH00652524 ). GoogleMaps   Jura Mountains , canton of Jura , Karstic spring near river Sorne, Blanches-Fontaines , 47° 17.338724'N, 7° 13.36608'E, 585m a.s.l., 06.04.2017, 1L, leg. J.-P.G. Reding, deposited in the MZL (catalogue number GBIFCH00652527 ). GoogleMaps  

Additional specimens. We examined many other specimens. These are stored in the collections of Jean-Paul G. Reding (RC), Bertrand Launay (BLC), Natural History Museum of Hungary (NHMH), Gilles Vinçon (GVC), Jacques Le Doaré ( JLDC), Alexandre Ruffoni ( ARC) and MZL.

SWITZERLAND

Jura Mountains

Chasseron region, Areuse river basin, canton of Vaud, Rhine tributaries:

 Small spring at Dénériaz coomb, 46° 51.180076'N, 6° 31.639395'E, 1135m, 20.09.1993, 3L; 31.07.1996, 1L   ; 13.10.1996, 1L   ; 30.08.2000, 1L   ; 10.05.2002, 1L   ; 18.07.2006, 4L   ; 29.06.2010, 1L (used for molecular studies by A. Reding), 1E; 04.05.2011,   1L (used for molecular studies by A. Reding);   18.05.2011, 1L   ; 04.07.2011, 1L   ; 13.12.2013, 1L   ; 27.08.2014, 1L (leg. J.-P.G. Reding; RC).  

 Dénériaz torrent, Noirvaux, 46° 51.228685'N, 6° 30.969797'E, 1000 m, 31.03.2005, 6L (leg. J.-P.G. Reding; RC);   13.08.2017, 1L, (leg. J. Le Doaré; JLDC).  

 Small spring, Poëta Raisse gorges, 46° 52.910488'N, 6° 36.307303'E, 1131m, 18.07.1997, 1E;   03.08.2011, 2L; 23.06.2012, 2L (leg. J.-P.G. Reding; RC). Orbe River Basin, canton of Vaud, Rhine tributaries:  

 Karstic spring Les Fontannets, La Mothe, 46° 49.165452'N, 6° 33.889242'E, 548m, 09.05.2014, 1L (leg. J.-P.G. Reding; MZL under catalogue number GBIFCH00284213, used for molecular studies by SwissBOL). Doubs Valley, canton of Jura, Rhône tributaries:  

 Karstic spring of Côte au Bouvier, near Soubey, 47° 18.028074'N, 7° 3.595063'E, 570m,   26.05.1997, 1♂, 2♀, 1E; 05.05.2009, 3♂;   16.06.2009, 2♂, 10♀, 2E; 20.06.2012, 4♀, 4E (leg. G. Vinçon; GVC);   12.06.2007, 3♂, 1E; 24.06.2007, 1♂, 1E (leg. R. Rupprecht; GVC);   29.05.2010, 5L (used for molecular studies by A. Reding);   14.07.2010, 1L (leg. A. Reding; RC);   20.09.2010, 11L; 23.09.2014, 2L (leg. J.-P.G. Reding; RC). Canton of Jura, Rhine tributaries:  

View Figure View Figure

 Karstic spring near river Sorne, Blanches- Fontaines, 47° 17.338724'N, 7° 13.36608'E, 585m, 10.03.2015, 1L (leg. J.-P.G. Reding; MZL under catalogue number GBIFCH00284212, used for molecular studies by SwissBOL); 06.04.2017, 1L (leg. J.-P.G. Reding; RC). FRANCE Jura Mountains Doubs Department (25) Doubs drainage basin, Rhône tributaries:    Spring of Doubs River, Mouthe, 46° 42.295779'N, 6° 12.548421'E, 946m, 18.04.1991, 2L; 15.09.1991, 1E (leg. J. Aubert; GVC);   14.07.1996, 1♀, 7E (leg. G. Vinçon; GVC);   13.06.2007, 1L (used for molecular studies by A. Reding);   10.05.2017, 1L (leg. J.-P.G. Reding; RC). Loue drainage basin, Rhône tributaries:  

 Spring of Loue River, Ouhans, 47° 0.645115'N, 6° 17.97486'E, 529m, 10.04.2013, 1L (leg. J.-P.G. Reding; RC).  

 Spring of Moulin Miguet, Nouailles Gorges, Ouhans, 47° 1.326046'N, 6° 17.934465'E, 456m, 14.05.2013, 1L;   01.04.2014, 5L; 14.04.2015, 2L (leg. J.-P.G. Reding; RC). Ain (01) and Jura (39) Departments, Ain drainage basin, Rhône tributaries:  

 Karstic spring near Albarine river, Charabotte Mill (01), 45° 57.308924'N, 5° 33.286347'E, 476m, 09.06.2013, 2♂, 3♀ (leg B. Launay; JLDC);   15.06.2013, 3♀;   16.02.2014, 2L; 06.05.2014, 1♂, 3♀, 1E (leg. B. Launay; RC); 13.05. 2015, 4m, 1L, 2E (leg. B. Launay; BLC; used for molecular studies by IRSTEA, numbers B116 and B117).  

View Figure

 Valouse river near Cornod (39), bridge over road D 202, 46° 18.536086'N, 5° 32.227764'E, 310m, 12.09.2007, 1L (leg. J. Le Doaré; JLDC).  

 Spring of Flumen river, near Les Moulins, Septmoncel (39), 46° 21.204252'N, 5° 54.395038'E, 800m, 24.07.2007, 9L; 28.04.2011, 1L (leg. J. Le Doaré; JLDC).  

 Spring of Ravin de la Gaillarde, Tenay (01), 45° 56,078220'N, 5° 32,239020'E, 651m, 13.04.2018, 1L (leg. B. Launay; BLC). Ain Department (01), Valserine drainage basin, Rhône tributaries:  

 Karstic spring at Creux-Godet, 46° 16.114284'N, 5° 54.894414'E, 879m, 13.04.1991, 1L (leg. J. Aubert; GVC);   17.03.2014, 2L;   30.05.2014, 1E (leg. B. Launay; BLC);   25.08.2014, 8L (leg. J. Le Doaré; JLDC).  

 Brion waterfall, near Chézery-Forens, 46° 15.311212'N, 5° 54.032052'E, 810m, 03.02.2014, 3L;   14.02.2014, 3L;   17.03.2014, 24L (leg. B. Launay; BLC; 2L in RC);   04.05.2014, 3L;   30.05.2014, 2♂, 2E;   19.07.2014, 1♀, 1E; 22.12.2014, 2L;   11.04.2015, 1L; 22.05.2015, 2L;   13.06.2015, 2♂, 1♀, 1E;   08.06.2016, 1♀ (leg. B. Launay; BLC);   27.01.2015, 3L (leg. J.-P.G. Reding; RC).  

 Karstic spring near Perissode farm, 46° 22.128147'N, 6° 0.361369'E, 1030m, 05.05.2014, 1L;   20.07.2014, 2♀; 25.08.2014, 11L (leg. J. Le Doaré; JLDC);   26.04.2015, 1L; 01.08.2015, 4L 1E (leg. B. Launay; BLC).  

 Forens river tributary, Chézery-Forens, 46° 13.389054'N, 5° 51.127375'E, 700m, 03.02.2014, 1L;   14.02.2014, 2L; 30.05.2014, 1♂, 1♀, 1E; 13.06.2015, 1E (leg. B. Launay; BLC).  

 Septfontaine river at Mijoux, 46° 19.277761'N, 5° 57.467904'E, 950m, 03.07.2015, 1L;   01.08.2015, 1♂, 1♀;   05.09.2015, 3L;   02.04.2016, 1L (leg. B. Launay; BLC).  

Diagnosis. General color dark brown with tawny and yellow spots ( Figs. 1 View Fig , 2 View Figs ). Males and females macropterous ( Figs. 1 View Fig , 8 View Fig ). Apex of the frontal sclerite of the epiproct of adult males slightly bent downwards, in lateral view ( Figs. 5 View Figs , 6 View Figs ). Female subgenital plate covering half of the ninth sternum and exhibiting a deep median arch-shaped notch ( Fig. 9 View Fig ). Body length of males 14–18 mm; females 15–23 mm. Anterior wings of males 15.9–17.6 mm; females 10–20.7 mm. Posterior

View Figure View Figure

wings of males 13.2–15.5 mm; females 13.9–20.5 mm.

Adults ( Figs. 1–9 View Fig View Figs View Figs View Figs View Fig View Fig ). Head mostly brown, with two large lateral yellow circular spots on both sides of the clypeus and a wide, symmetric, yellow patch on the M-line, above the anterior ocellus ( Fig. 2 View Figs ). Between the lateral ocelli, a large, tawny area delimitated posteriorly by the epicranial suture. Area between the lateral ocelli and the compound eyes pale yellow ( Fig. 2 View Figs ). Pronotum dark brown ( Fig. 2 View Figs ). Anterior and posterior angles of pronotum almost rectangular ( Fig. 2 View Figs ). Presence of a yellow median band extending from the anterior margin of the pronotum to its posterior margin, widened in its middle section and gradually narrowing toward the posterior margin of pronotum ( Fig. 2 View Figs ). A tawny area on each side of the pronotum, with dark, sculpted rugosities ( Fig. 2 View Figs ). Abdominal sterna pale brown, with symmetrical, hyphen-like patches. Proximal part of tibiae with a dark band. Antennae and cerci blackish to dark brown ( Figs. 1 View Fig , 4 View Figs ). Wing venation as typical for the genus ( Ris 1896: 308, Fig. 3 View Figs ). Forewing ( Fig. 8 View Fig ) and hindwing (cf. Fig. 31 View Fig ) with the two cross-veins “ra- rp” and “rp- ma” nearly aligned. Numerous cross- veins forming a reticulated area between RA and RP ( Fig. 8 View Fig ). Cross-vein “ra- rp” and subcostal area of forewing faintly infuscate ( Fig. 8 View Fig ).

Male terminalia ( Figs. 3–6 View Figs View Figs View Figs ). Presence of distinctly separated hemiterga ( Figs. 3 View Figs , 4 View Figs ) and an epiproct with a frontal apical sclerite ending in a single long spine and with two shorter dorso-lateral spines ( Figs. 5 View Figs , 6 View Figs ). Epiproct flanked by flat and spatulate lateral stylets ( Figs. 5 View Figs , 6 View Figs ). Tergum 10 divided into hemiterga whose lobes are covered with 20 to 25 pale long setae in which 2 to 9 darker, stronger and longer spines (half of the length of the hemitergal lobes) are embedded ( Fig. 3 View Figs ). Hemitergal lobes long and slender, bent obliquely upwards ( Fig. 3 View Figs ) and rearwards ( Fig. 4 View Figs ). Apex of frontal sclerite of epiproct slightly bent downwards, in lateral view ( Figs. 5 View Figs and 6 View Figs ). Lateral stylets large and clubshaped, widening near apex, in lateral view ( Figs. 5 View Figs and 6 View Figs ). Abdominal sternum 7 composed of multiple plates ( Fig. 7 View Figs ).

Females ( Fig. 9 View Fig ). Females of Dictyogenus   not formally identifiable to species level, except those of D. alpinum   , whose subgenital plate covers the majority of the sternum 9 ( Figs. 60, 61 View Figs ). Female subgenital plate of D. jurassicum   sp. n. covering half of the ninth sternum and exhibiting a deep median arch-shaped notch ( Fig. 9 View Fig ).

View Figure View Figure

Mature larvae ( Figs. 10–19 View Fig View Figs ). Larvae <8 mm not identifiable to species-level. Immature larvae are characterized by a very dense setation on abdominal segments, legs, paragenital plates as well as cerci and live in interstitial habitats composed of loose sandy gravels. Mature larvae, on the contrary, are petricolous and this habitat shift also coincides with important chaetotactic changes, notably the reduction of length and number of setae on abdominal segments, paragenital plates and cerci.

Length of mature larvae, measured from head to end of abdomen: 9–19 mm. First two abdominal segments with abdominal terga and sterna clearly separated by a small membranous area ( Fig. 19 View Figs ). Interocellar area with a narrow yellow patch not reaching lateral ocelli ( Figs. 10 View Fig , 11 View Figs ). Lateral ocelli without circum-ocellar yellow patch ( Figs. 10 View Fig , 11 View Figs ). A narrow elongated yellow patch above each lateral ocellus ( Figs. 10 View Fig , 11 View Figs ). M-line indistinct ( Figs. 10 View Fig , 11 View Figs ). Occipital fold and lower rim of the eyes with a conspicuous row of spines ( Fig. 11 View Figs ; cf. also Fig. 66 View Figs ). Lacinia with apical and subapical tooth; marginal setae of the lacinia in a single long row ( Fig. 12 View Figs ). Lacinia, below subapical tooth, with a shoulder-like angle ( Fig. 12 View Figs ; cf. also Fig. 64 View Figs ). Shape of pronotum ovoid ( Fig. 11 View Figs ). Medio-dorsal setae on pronotum short and scattered, arranged as several, loosely demarcated rows ( Fig. 13 View Figs ). Medio-dorsal row of setae long and continuous on mesonotum and metanotum ( Fig. 14 View Figs ). Medio-dorsal row of setae on abdominal terga short and sparse ( Fig. 15 View Figs ). Posterior margins of median abdominal terga with setae of unequal lengths ( Fig. 18 View Figs ). Tip of paragenital plates blunt, in ventral view ( Fig. 17 View Figs ). Paragenital plates, in ventral view, with at most two unpaired spines at or near apex; generally, there is only 1 spine on one of the paragenital plates while the other is devoid of spines ( Fig. 17 View Figs ). Numerous empty spine insertion points on the paragenital plates, in ventral view ( Fig. 17 View Figs ). Mediodorsal row of swimming-hairs of caudal setae sparse, with interruptions, and as long as or not much longer than the diameter of the cerci ( Fig. 16 View Figs ). General aspect as in Fig. 10 View Fig .

Egg characteristics ( Figs. 20–25 View Figs ). General shape oblong, cross-section trilateral, smoothed ( Figs. 20–22 View Figs ). Posterior pole of egg regularly rounded; ridges only slightly protruding ( Figs. 20–22 View Figs ). Chorionic surface with granulose follicle cell impressions ( Fig. 23 View Figs ). Collar short, flared apically with few ridges of different length (fig. 24). Anchor flat ( Fig. 25 View Figs ). Micropyles protruding and arranged singularly near posterior ⅓ of egg ( Fig. 23 View Figs ). Eclosion line absent.

View Figure

Comparison to Congeners.

Adults. In the adult male of Dictyogenus jurassicum   sp. n., the hemitergal lobes are strongly bent upwards ( Fig. 3 View Figs ) and rearwards ( Fig. 4 View Figs ), whereas the hemitergal lobes of D. alpinum   are only slightly bent upwards, pointing almost horizontally toward each other ( Fig. 56 View Fig ). In the adult males of Dictyogenus jurassicum   sp. n. (and also those of D. muranyii   sp. n. and the specimens belonging to the D. fontium   species complex), there is a wide, Vshaped membranous area between the hemitergal lobe and the inner anterior corner of the hemiterga ( Figs. 3 View Figs , 29 View Figs , 32 View Figs , 81 View Figs ). In the adult males of Dictyogenus alpinum   , on the contrary, the area between the hemitergal lobe and the inner anterior corner of the hemiterga is globulous and sclerotized ( Fig. 56 View Fig ). In Dictyogenus jurassicum   sp. n., the lateral stylets are enlarged apically ( Fig. 5 View Figs ), whereas they are getting progressively thinner toward the apex in D. alpinum   ( Fig. 57 View Fig ). In the female of Dictyogenus jurassicum   sp. n., the subgenital plate ( Fig. 9 View Fig ) covers at most the upper half of abdominal sternum 9, as is also the case for specimens of the D. fontium   species complex ( Figs. 83 View Fig , 84 View Fig ), whereas the subgenital plate of D. alpinum   covers ¾ of the sternum 9 ( Figs. 60, 61 View Figs ). Adult females of Dictyogenus jurassicum   sp. n. hence have more affinities with those of the D. fontium   species complex than with those of D. alpinum   , whereas adult males of Dictyogenus jurassicum   sp. n. are closer to those of D. alpinum   than to those of the D. fontium   species complex, from which they differ by the much stronger curvature of the apex of the frontal epiproct sclerite in lateral view ( Figs. 5 View Figs , 6 View Figs , 57 View Fig compared to Fig. 80 View Figs ).

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

Distribution and ecology. Dictyogenus jurassicum   sp. n. is the only species of Dictyogenus   present in the Jura Mountains of France and Switzerland ( Fig. 92 View Fig ) and is distributed over all its different drainage basins. The occurrence of Dictyogenus jurassicum   sp. n. is, however, restricted to karstic springs (some of them intermittent) and the initial section of their outflows in the Jura Mountains of France and Switzerland ( Fig. 26 View Fig ). The flight period of D. jurassicum   sp. n. extends from spring to early summer. Adults of both sexes emerge from the middle of April until the beginning of July. The life cycle is unknown. Our observations in the field are compatible with a semivoltine cycle, since immature larvae (3-4 mm) were generally found together with pre-emergent larvae in spring, at the end of the emergence period of adults. Half-grown larvae (6-8 mm) are present in autumn and in winter. Thus, larval growth of Dictyogenus jurassicum   sp. n. extends over a period of at least two years. A possible egg diapause, as documented for a population of Dictyogenus fontium   by Zwick & Zwick 2010, would extend its life cycle to three years.

View Figure

Etymology of Dictyogenus jurassicum   sp. n. The new species is named after the region where it was collected, the Jura Mountains of France and Switzerland.

MZL

Musee Zoologique

ARC

Atlantic Reference Centre

R

Departamento de Geologia, Universidad de Chile

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Plecoptera

Family

Perlodidae

Genus

Dictyogenus

Loc

Dictyogenus jurassicum Reding, Launay, Le Doaré, Ruffoni & Vinçon

Reding, Jean-Paul G., Launay, Bertrand, Doaré, Jacques Le, Ruffoni, Alexandre & Vinçon, Gilles 2019
2019
Loc

Dictyogenus alpinum

Verneaux et al. 2003: 71
2003
Loc

Reding, J.-P.G. 1998: 42
1998
Loc

Dictyogenus (Besdolus) ventralis

Verneaux, J 1973: 98
1973