Cybaeus minor Chyzer, 1897

Isaia, Marco & Chiarle, Alberto, 2015, Taxonomic notes on Cybaeus vignai Brignoli, 1977 (Araneae, Cybaeidae) and Dysdera cribrata Simon, 1882 (Araneae, Dysderidae) from the Italian Maritime Alps, Zoosystema 37 (1), pp. 45-56 : 50-52

Cybaeus minor Chyzer, 1897

( Fig. 4C )

Cybaeus minor Chyzer in Chyzer & Kulczyn’ski, 1897: 153, plate 6, fig. 9. — Loksa 1969: 116, fig. 79C, G. — Brignoli 1978 g: 508, figs 76-78. — Polenec 1985: 103, figs 5-7. — Maurer 1992: 151, figs 9-12, 15, 17.

MATERIAL EXAMINED. — Italy. Lombardia (BG): 2♂, 1♀, moraine, road to Passo Campelli, Schilpario, 1750 m, 28.VII-18.X.2005, leg.

Museo di Scienze BG (coll. MI). Veneto ( TV): 1♀, Monte Grappa, Bassano, 28.IX.1977, leg. K. Thaler ( IZUI A7115) [sub C. intermedius in Maurer (1992)].

REMARKS

Considering the genital morphology of males and females of the minor group, the match between male and female of C. vignai suggested by Maurer & Thaler (1988) seems highly questionable. The hypothesis of a misidentification is supported by the co-occurrence of the newly collected males with females of C. vignai . Additionally, we found at the same localities females of C. intermedius and males corresponding to that illustrated in Maurer & Thaler (1988) as C. vignai . When examining material from Maritime Alps and comparing it to C. intermedius from different Italian localities, it became clear that the previous “doubtful male” (and part of the males found in our samplings), belongs in reality to C. intermedius . The same is the case for the male illustrated in Isaia et al. (2011: 92, 152, figs A, B, C) and wrongly attributed to C. vignai .

Concerning the identification of females, the borders and the upper vertices of the atrium are the most diagnostic characters allowing the separation of the species. In C. intermedius the upper border is thickened at the vertices and the lateral borders are clearly visible. In C. montanus the upper vertices are similar to those of C. intermedius , but the lateral borders are only weakly visible. In C. minor the upper border of the atrium is strongly thickened, the vertices are rounded and the lateral borders are clearly visible ( Fig. 4 ).

Similarly, examination of the females from the Maritime Alps identified as C. montanus by in Maurer (1992) revealed that they belong instead to C. intermedius . Consequently, it seems reasonable to assume that all previous records of C. montanus from the Maritime Alps as well as from the western Alps, including the two females of C. angustiarum from the Maritime Alps cited by Brignoli (1977: 30, fig. 6) and cited in Isaia et al. (2007), belong to C. intermedius . The presence of C. montanus in the western Alps is thus not supported anymore.

Concerning C. minor , we examined material of this species from Veneto that was wrongly reported in Maurer (1992) as C. intermedius . Hence we question the presence of C. intermedius in the eastern Alps.

According to the morphology of the palp and female internal genitalia, C. vignai seems more closely related to C. raymondi (Simon, 1916) (endemic to French Pyrenees) and C. tetricus (C. L. Koch, 1839) (central Europe) than to the species of the minor group discussed by Maurer (1992: 153, figs 25-26, 29-30).

In their recent revision of the Nearctic species of Cybaeus, Copley et al. (2009) groups the Holarctic and Nearctic species in eight species group, which are partially supported by molecular evidence. According to the in-line position of the spermathecal heads in respect to the rest of the vulval ducting, and according to the presence of a relatively large epyginal atrium, the species of the minor group, as well as C. vignai , are assigned to the tetricus group.

DISTRIBUTION ( FIG. 5 )

Records of C. vignai are so far restricted to a few localities in the Italian and French Maritime Alps. Males have been found at two Italian localities (Valle Gesso: Palanfrè and Bousset), while previous records of females are given by Isaia et al. (2011) and citations therein (Valle Pesio: Certosa di Pesio; Valle Vermenagna: Vernante), and by Maurer and Thaler (1988) ( France: Forêt de Turini: Le Moulinet). According to our interpretation, previous records of males have to be referred to C. intermedius . However, it is likely that the species is more widespread in the SW Alps. According to the new records, the distribution of C. intermedius extends from Tessin and Bergamo Prealps, across the western Alps and down to the French and Italian Maritime Alps (where it occurs sympatrically with C. vignai ), the Ligurian Apennines and, according to Pesarini (2003), down to the Tuscan-Emilian Apennines. C. intermedius is here recorded for the first time in France.

According to our findings, C. montanus seems to be restricted to the Prealps of Lugano and Bergamo. Records from Veneto ( Ballarin et al. 2011) and Toscana ( Maurer 1992) remain to be verified.

HABITAT AND PHENOLOGY

The three species of Cybaeus dealt with here occur predominantly in the litter of broad-leaved forest, especially beech, although C. vignai , is also found in caves ( Isaia et al. 2011). Adults are generally collected in summer.

Figures

FIG. 4. — Epigynal atrium, ventral view: A, Cybaeus intermedius Maurer, 1992,, from Trinità di Entracque; B, C. montanus Maurer, 1992, from Monte Generoso, Poma; C, C. minor Chyzer, 1897, from Passo Campelli, Schilpario. Scale bar: 0.2 mm.

FIG. 5. — Distributions of Cybaeus intermedius Maurer, 1992, C. montanus Maurer, 1992, C. minor Chyzer, 1897, C. tetricus C. L. Koch, 1839 and C. vignai Brignoli, 1977. Black symbols refer to literature data, white symbols refer to material examined here.