Perla pyrenaica, Reding, 2023

Reding, Jean-Paul G., 2023, Steps towards a revision of the Perla bipunctata Pictet, 1833 species complex (Plecoptera: Perlidae), Fragmenta entomologica (Frag. Entomol., Roma) 55 (2), pp. 221-262 : 229

Perla pyrenaica sp. n.

( Figs E.1–E .15) urn:lsid:zoobank.org:act:7F837839-7A51-475E-9CC7-A4D528F09E6E

Perla maxima ; Despax 1951: 190; Bertrand & Aubert 1952: 96; 1955; Aubert 1963: 79.

Perla grandis ; Berthélemy & Laur 1975: 278; Oscoz & Durán 2004: 188; Tierno de Figueroa et al. (2003: 112; 2015b; 2018)

Morphological diagnosis. Males and females macropterous. Body length of males 18–26 mm; of females 20–36 mm. Body colour dark brown. Head mostly yellow with tawny markings; M-line clearly delineated ( Fig. E.1 ). Pronotum pale yellow, with a large dark central band flanked with a symmetrical darker design ( Fig. E.1 ). Inner half of the two lower ocelli circled by a narrow black band ( Fig. E.1 ) on most, and by a large black band (Fig. E.2) on some specimens. This type corresponds to putative Perla grandis from the Pyrenees.

Type material. Holotype male: FRANCE. Occitania. Hautes-Pyrénées; tributary to Estaragne , cote 2193, 2240 m, 21 Jun 2022, 1♂, leg. B. Launay ( MZL).

Paratypes: FRANCE. Occitania. Ariège, Albiès , Gargante brook, 790 m, 21 Jul 1986, 1♂ with separat- ed aedeagus, leg. J. Aubert ( MZL, catalogue number: GBIFCH00913253) . SPAIN. Lleida. Bono, Noguera Ribagorzana , 1100 m, Jul 1951, 1♂ microscopic prepa- ration, leg. H. Bertrand ( MZL, catalogue number: GBIFCH00913240) .

Additional material is listed in the Appendix 1, under type E.

Male adults. Sclerotized apex of aedeagus slightly bulging out in its middle section ( Fig. E.3 ). Proximal part of aedeagus with a strong row of aligned brush-like setae ( Fig. E.3 ); distal part terminated by two narrow blunt ends, medially interrupted ( Fig. E.3 ). Length of aedeagus: 0.65 mm; width: 0.30 mm. Aedeagal tube with parallel sides ( Fig. E.4 ) and covered by a dense grid of short setae ( Fig. E.5 ). Mesal field on tergite IX short and narrow, with few spiny projections, and shallow distal division (Figs E.6, E.7). Distal side of hemitergal lobes of tergite X apically enlarged, in lateral view (Fig. E.8). Apex of hemitergal lobes with very strong spines (Fig. E.8).

Morphological affinities. Adult males of types E and F are separable by the shape of the sclerotized apex of their aedeagus. Whereas the one of Perla pyrenaica sp. n. ends into two blunt extensions ( Fig. E.3 ), putative specimens of Perla bipunctata from the Pyrenees (type F) have a much shorter, and distally indented aedeagus ( Fig. F.1 ). Perla pyrenaica sp. n. ( Fig. E.3 ) differs from alpine P. grandis ( Figs. A.4 , A.8) by its much shorter and medially enlarged apex of its aedeagus.

Female adults. Subgenital plate with two distinct triangular extensions (Fig. E.9).

Nymphs. Length: 24 to 36 mm. Pronotum with a large, dark, central stripe flanked by two irregularly shaped dark bands loosely connected to the upper and to the lower edges of the pronotum ( Figs. E.10 , E. 11 ). Rim of pronotum with a wide, half-circled dark band ( Fig. E.10 ). Lateral edges of pronotum yellow ( Fig. E.10 ). Yellow markings on tergites III to V dot-like, medially separated by a dark stripe ( Fig. E.12 ). Dorsal faces of femora of middle and hind legs with an indistinct dark area connected to the dorsal edge of the femora ( Fig. E.13 ). Cerci with separated bunches of basal mediodorsal setae (Fig. E.14). Tergites with long mediodorsal flexible setae, in lateral view. Paraprocts with conical apex (Fig. E.15).

Morphological affinities. Nymphs of Perla pyrenaica sp. n. are characterized by the presence of separated bunches of basal mediodorsal setae on their cerci (Fig. E.14), whereas P. grandis nymphs exhibit a continuous row of long, mediodorsal setae (Figs. A.14, A.15).

Distribution. This species is known from high altitude brooks and springs on both slopes of the Pyrenees. The material is listed in the Appendix 1, under type E.

Derivation nominis. This species is named after the region which it inhabits. The adjective pyrenaica is to be treated as a feminine Latin adjective in the nominative case combined with Perla .

Figures

Plate I, Figs A.1–A.9 – Type A (Italian Alps and Apennines). A.1, hemitergal lobes, mesal field with sensilla and sclerotized apex of everted aedeagus of an adult ♂ (Soana); A.2, sclerotized apex of everted aedeagus of an adult ♂ (Staffora); A.3, sclerotized apex of extracted aedeagus of an adult ♂ (Stura di Ala); A.4, sclerotized apex of everted aedeagus of an adult ♂ (Soana); A.5, aedeagal tube of adult ♂; A.6, aedeagal tube and hemitergal lobes of adult ♂; A.7, adult ♂, hemitergal lobes and mesal field with sensilla (Southern Apennines); A.8, sclerotized apex of extracted aedeagus of an adult ♂ (Southern Apennines); A.9, adult ♂, hemitergal lobes and mesal field with sensilla, dorsal view (Stura di Demonte).

Plate XV, Figs F.3–F.8 – Type F (putative Perla bipunctata from the foothills of the Pyrenees, Río Aragón). F.3, head and pronotum of nymph; F.4, tergites of nymph, dorsal view; F.5, tergites of nymph, dorsal view; F.6, markings on femora; F.7, paraprocts of nymph, ventral view; F.8, cerci of nymph, lateral view.

Plate III, Figs A.16–A.21 – Type A (French and Swiss Alps). A.16, head and pronotum of nymph (Swiss Alps); A.17, markings on tergites of nymph (Gryonne valley); A.18, markings on tergites of nymph (Sense); A.19, markings on the femora of legs, dorsal view (Gryonne Valley); A.20, sclerotized apex of extracted aedeagus of an adult ♂ (Vercors); A.21, sclerotized apex of aedeagus of Perla grandis, from Aubert 1949: 225, his Fig. 4.

Plate IX, Figs C.13–C.18 – Type C (nymphs, Nure, Rivers Aare and Emme). C.13, head and pronotum of nymph (Nure); C.14, mediodorsal setation on tergites, lateral view (Nure); C.15, paraprocts, ventral view (Aare); C.16, head and pronotum of nymph (Aare); C.17, oval markings on femora (Emme); C.18, sclerotized apex of aedeagus of Perla bipunctata, from Aubert 1949: 225, his Fig. 5.

Plate II, Figs A.10–A.15 – Type A (male and female adults, nymphs). A.10, adult ♂, hemitergal lobes, lateral view (Southern Apennines); A.11, head and pronotum of an adult ♂ (Stura di Demonte); A.12, subgenital plate of adult ♀ (Stura di Demonte); A.13, subgenital plate of adult ♀ (Haute-Savoie); A.14, basal section of cerci of nymph (Staffora); A.15, basal section of cerci of nymph (Gryonne valley).

Plate XIV, Figs F.1–F.2 – Type F (putative Perla bipunctata from the foothills of the French Pyrenees). F.1, illustrations of Despax (1942, his Figs 11, 12. Fig. 11 = adult ♂b with everted aedeagus, lateral view; Fig. 12 = adult ♂b, sclerotized apex of aedeagus); F.2, illustrations of Despax (1951, his Fig. 86, D, E, F. D = adult ♂b, mesal field with sensilla; E = adult ♂b, mesal field; F = adult ♂b, hemitergite).