Protonemura gevi, Figueroa, José Manuel Tierno De & López-Rodríguez, Manuel Jesús, 2010

Figueroa, José Manuel Tierno De & López-Rodríguez, Manuel Jesús, 2010, Protonemura gevi sp. n., a cavernicolous new species of stonefly (Insecta: Plecoptera), Zootaxa 2365, pp. 48-54 : 48-53

publication ID	https://doi.org/ 10.5281/zenodo.275760
DOI	https://doi.org/10.5281/zenodo.6195999
persistent identifier	https://treatment.plazi.org/id/714787DE-FFA1-FFAF-FF07-645D35EF1919
treatment provided by	Plazi
scientific name	Protonemura gevi
status	sp. nov.

Treatment

Protonemura gevi View in CoL sp. n. Tierno de Figueroa & López-Rodríguez

Figs. 1–4 View FIGURE 1 View FIGURE 2 View FIGURE 3 .

Type Material: Holotype: Spain, Jaén, Siles, Cueva del Nacimiento del Arroyo de San Blas (cave of the San Blas stream source), 1000 m a.s.l., coordinates: 38º23’12.94’’ N, 2º32’06.10’’ W, 60 m deep in the cave, 19- VII-2009, 1 male, G.E.V. leg. Paratypes: same locality, date and collectors, 5 males, 6 females, 10 nymphs (5 males and 5 females).

The holotype and some paratypes (2 males, 3 females, 2 male nymphs and 2 female nymphs) are deposited in the Collection of the Museo Nacional de Ciencias Naturales (Madrid, Spain) with the identification codes: Nº Cat. TIPOS MNCN 1937. The remaining paratypes (3 males, 3 females, 3 male nymphs and 3 female nymphs) are deposited in the Tierno de Figueroa’s collection in the Departamento de Biología Animal, Universidad de Granada ( Granada, Spain).

Other material examined: same locality, date and collectors, 9 nymphs.

Type locality: Cueva del Nacimiento del Arroyo de San Blas (cave of the San Blas stream source) (Siles, Jaén, Spain).

Etymology: The specific name of this taxon is in honour of the speleological group of Villacarrillo (G.E.V., Grupo Espeleológico de Villacarillo) that collected the specimens.

Diagnosis. Body length: males 6.1–8.0 mm (holotype 8.0 mm), females 6.9–8.4 mm. Forewing length: males 4.2–4.7 mm (holotype 4.4 mm), females 5.0– 5.9 mm.

Habitus. Head ( Fig. 1 View FIGURE 1 A) brown and yellow: yellowish background, with a dark brown triangular zone among the ocelli, a central dark brown zone in the occiput, two light brown rounded areas between the occiput and the posterior ocelli, dark brown areas rounding the antennae bases and extending along the clypeuslabrum area with a small yellow zone at the frons. Compound eyes scarcely prominent. Antennae very dark except in the basal area (yellow) and very long, longer than the body length ( Fig. 4). Prosternal gill remnants white, slender and short, without narrowing. Pronotum dark brown, with a yellow triangle posteriorly and light brown anterolaterally ( Fig. 1 View FIGURE 1 A). Meso- and metanotum yellowish at the prescutum, and brown at the scutum and scutellum. Legs yellow with brown transversal bands in the femur. Wings brachypterous in both sexes. Abdomen yellowish with the last segments brown, from the eighth segment in males and from the ninth segment in females. Cerci cylindrical with the apex narrower than the base, particularly long in some males in comparison with others.

Male: Eighth abdominal tergum with one or two small black setae at each side of the central line. Ninth abdominal tergum with two posteriorly protruding lobes covered with many black setae. Hypoproct subpentagonal with its posterior apex long, finger-shaped ( Fig. 2 View FIGURE 2 A). Vesicle long, as long as the length of the ninth sternite. Epiproct: laterally unique, with a pronounced white hump midway on the dorsal sclerite ( Fig. 2 View FIGURE 2 C), apex pointed and slightly curved upwards, ventral sclerites with a rounded, spine-bearing projection; dorsally, the epiproct is long and rounded distally ( Fig. 2 View FIGURE 2 B); apical tubelike projection absent. Paraproct ( Fig. 2 View FIGURE 2 D): inner lobes not hidden by the hypoproct ( Fig. 2 View FIGURE 2 A); sclerotized base of median lobes subtriangular, inner branch darkly sclerotized, short and enlarged in its apex, membranous portion bulbous and covered with small hairs; outer lobes sclerotized, hammer-shaped (notably enlarged apically), slightly curved across the top of the median lobe and bearing black thick setae in the apex.

Female: Pregenital plate (seventh sternum) slightly protruding over the eighth sternum and slightly sclerotized in its central part ( Fig. 2 View FIGURE 2 E). Subgenital plate trapezoidal, widest anteriorly, the posterior margin having a shallow emargination; the vaginal lobes well visible, extending from the corners of the subgenital plate. Paraproct rounded, slightly wider than long.

Mature nymph: Body length: males 5.9–7.0 mm, females 8.2–10.0 mm. General colour yellowish-brown. Legs, antennae and cerci also yellowish brown but lighter. Body nearly without setae, except in the legs and the cerci, where small setae are present. Head (including eyes) approximately as wide as the pronotum ( Fig. 3 View FIGURE 3 A). Prosternal gills ( Fig. 3 View FIGURE 3 B), as in adults, white, slender and short, without narrowing. Pronotum almost rectangular, widest anteriorly ( Fig. 3 View FIGURE 3 A). Pronotum marginal setae continuous and short, longest at corners. Mesonotum with hairs in the proximal corners longer than those of the pronotum. Legs with dorsolateral dark setae on the femur that are 1/3 femur width, shorter dark setae on the tibiae mainly found on distolateral margin ( Fig. 3 View FIGURE 3 A&B). Abdominal segments 1–6 divided into tergum and sternum. Abdominal terga sparsely populated by small, short setae throughout the tergum, a close set row of setae at the posterior margin of each segment, paired spines lacking ( Fig. 3 View FIGURE 3 C). Paraprocts with sparse pilosity, triangular in ventral view, proportionally longer in the female nymph, with tip rounded in the female, truncate in the male ( Fig. 3 View FIGURE 3 E&D). Cerci longer than the abdomen, with short hairs in the distal margin of each article, with the first articles wider than longer (approximately until the tenth), becoming progressively longer in relation to width distally.

Affinities. Morphologically, P. gevi sp. n. is clearly different from the remaining Iberian Protonemura species, and cannot be included in currently recognized groups ( Vincon & Muranyi, 2009). The most similar Iberian species is P. culmenis Zwick & Vinçon, 1993 which is isolated in the Pyrenees ( Vincon & Muranyi, 2009). The female pregenital plate is similar in both species, but wider in P. gevi sp. n. The epiproct of P. gevi sp. n. has a characteristic hump formed by the distal third of the ventral sclerite, not so prominent in P. culmenis . The paraprocts of males of the two species differ mainly in the shape of the inner branch of the median lobes. In P. culmenis the branch is finger-shaped, while in P. g e v i it is enlarged in its apex. The general pilosity is much scarcer in P. g e v i sp. n. than in P. culmenis .

Regarding additional Protonemura species, some similarities can be found in the shape of the male paraprocts and the female subgenital plate with the North African talboti subgroup of the corsicana group (especially to P. b e r b e r i c a Vinçon & Sánchez-Ortega, 1999), but the absence of the apical tubelike projection in the epiproct of P. g e v i sp. n. indicates that this species does not belong to the corsicana group.

Particularly similar to P. g e v i sp. n. is P. hassankifi Aubert, 1964 from Iran, mainly by the paraproct shape, although the epiproct does not present a hump so prominent. The subgenital plate of the P. hassankifi female is similar but without the median depression.

P. gevi has scarcely prominent compound eyes in comparison with the only two other Protonemura species from Southern Iberian Peninsula [ P. alcazaba (Aubert, 1954) and P. meyeri (Pictet, 1841) ] ( Fig. 1 View FIGURE 1 ) and also in comparison with other Palearctic Protonemura species that we could study [ P. angelieri Berthélmy, 1963 , P. aroania Tierno de Figueroa & Fochetti, 2001, P. auberti Illies, 1954 , P. beatensis (Despax, 1929) , P. berberica , P. canigolensis Zwick & Vinçon, 1993, P. caprai (Aubert, 1954) , P. consiglioi (Aubert, 1953) , P. culmenis , P. globosa Berthélemy & Whytton, 1980, P. hiberiaca Aubert, 1963 , P. hispanica (Aubert, 1956) , P. intricata (Ris, 1902) , P. lateralis (Pictet, 1835) , P. navacerrada (Aubert, 1954) , P. praecox (Morton, 1894) , P. pyrenaica Mosely, 1930 , P. ruffoi Consiglio, 1961 , P. salfii (Aubert, 1954) , P. talboti (Navás, 1929) , P. tuberculata (Despax, 1929) and P. vandeli Berthélemy, 1963 ].

The P. gevi sp. n. nymph does not present, as P. nimborum (Ris, 1902) , paired spines in the abdomen terga frequently found in some other Protonemura species, but the lack of many Protonemura nymph descriptions does not let us to discuss this character further.

Ecological remarks. This species, both adults and nymphs, was collected at 60 m depth from the exit of the cave of the San Blas stream source ( Fig. 5 View FIGURE 5 ), an unusual habitat for a stonefly. The abiotic characteristics were: 67% humidity, 7ºC water temperature, 9ºC air temperature, total absence of light, clear oligotrophic water, and substrate composed mainly by cobble and gravel, but also of sand and lime precipitate.

Protonemura gevi sp. n. is abundant but probably localized in the study area. In 2002, M. Baena and A. Pérez Ruiz collected some stonefly individuals in the same cave. Unfortunately, this material was lost in the mail. After the collection of the typical series in July 2009, a new visit to this area in August 2009 by T. Pérez Fernández led to the observation of many nymphs and adults. A visit on 7 September, 2009 resulted in the observation of 4 adults and 2 mature nymphs in the cave, but these were not collected. No further collections were made because we did not know the status of the population and its restricted distribution area probably makes it threatened. The presence of mature nymphs and adults in July, August and September indicates a summer flight period for this species, but given the potentially stenothermic nature of the stream habitat, it is possible that emergence extends to other seasons.

No individuals were found out of the cave and, although more samplings are needed to completely confirm it, it is possible that the distribution area of this species is limited to this cave and, perhaps, to some nearby cavities. Thus, considering the relatively good taxonomic knowledge of the stonefly fauna of the Southern Iberian Peninsula, this species could be considered a microendemic.

It is usually accepted that aquatic insects inhabiting caves do not exhibit discernible modifications from a hypogean existence ( Ward 1992). Nevertheless, P. g e v i sp. n. has relatively small eyes in comparison with other Protonemura species, antennae in adults are considerably long, longer than the body length, and both sexes present a notable degree of wing reduction. This last character is usually associated with populations living in high mountains or to only one of the sexes, not both. We think that this wing reduction in both sexes of P. g e v i sp. n., and small compound eyes and specially the long antennae, are probably a consequence of environmental pressures of this particular habitat.