Centromerus tongiorgii, Ballarin & Pantini, 2020

Ballarin, Francesco & Pantini, Paolo, 2020, Three new species and new records of the genus Centromerus (Araneae, Linyphiidae) from Italy, European Journal of Taxonomy 660 (660), pp. 1-23 : 3-7

Centromerus tongiorgii sp. nov.

urn:lsid:zoobank.org:act:19C54F31-6D19-4624-8A63-82FA97B9E620

Figs 1–2 , 10

Diagnosis

The new species is morphologically closely related to Centromerus isaiai , C. hanseni sp. nov. and C. sylvaticus . Male C. tongiorgii sp. nov. can be distinguished from male C. isaiai by the slimmer, thread-like second radical apophysis (RA-II), which appear thicker and sturdier in the latter species, and by the larger, more rounded median tubercle of the cymbium (MT) which is smaller and more pointed in C. isaiai ( Figs 1 A–B, 2A–C vs Bosmans & Colombo 2015: figs 4–6, 10). Males of the new species are separated from male C. hanseni sp. nov. by the triangular shape of the dorsal hump (DT), which appears flatter and more squared in C. hanseni sp. nov., and by the presence of a median tubercle (MT), lacking in C. hanseni sp. nov. ( Figs 1 A–B, 2A–B vs Figs 3 A–B, 4A–B). In addition, the two species can be separated by the shorter and poorly visible radical apophysis I (RA-I) in C. tongiorgii sp. nov., which is always clearly visible in C. hanseni sp. nov. when the palp is observed prolaterally or retrolaterally, and by the lack of any apophysis on the distal part of the paracymbium (APC), present instead in C. hanseni sp. nov. ( Figs 1 A–C, 2A–C vs Figs 3 A–C, 4A–C). Male C. tongiorgii sp. nov. can easily be distinguished from male C. sylvaticus by the smaller size (1.69–2.25 vs 2.2–4.0), by the lack of teeth on the lateral margin of the paracymbium (P), which is armed with teeth in C. sylvaticus , and by the slimmer and more curved radical apophysis II (RA-II) in contrast to the thicker and straighter RA-II in C. sylvaticus (see Figs 1A , 2A vs Roberts 1987: fig. 64a). Females of the new species are separated from those of C. isaiai and C. sylvaticus by the shorter anterior wall (AW) with a wider base and ending with a sharp point, instead of a long lobe as in the latter two species (see Figs 1E , 2D vs Bosmans & Colombo 2015: figs 7, 8, 12 and Roberts 1987: fig. 64a). The different shape of the posterior median plate (PMP) further distinguishes these species, as the PMP is rectangular in C. tongiorgii sp. nov., in contrast with a squared PMP in C. hanseni sp. nov., a triangular PMP in C. isaiai and a trapezoid PMP in C. sylvaticus (see Figs 1G , 2E vs Fig. 3G, E vs Bosmans & Colombo 2015: fig. 13 and Wiehle 1956: fig. 55). In addition, female C. tongiorgii sp. nov. are easily distinguished from female C. sylvaticus by their smaller size (1.8–2.1 vs 3.5–4). Female C. tongiorgii sp. nov. are distinguished from female C. hanseni sp. nov. by the sharp tip of the anterior wall (AW), lacking a truncated ending as in C. hanseni sp. nov., and by the narrower posterior median plate (PMP), which is larger in C. hanseni sp. nov. ( Figs 1E, G , 2 D–E vs Figs 3E, G , 4 D–E).

Etymology

The specific name is a patronym in honour of Prof. Paolo Tongiorgi, a well-known Italian zoologist who passed away in 2018. Tongiorgi extensively contributed to the study of the taxonomy and biology of European spiders of the family Lycosidae .

Material examined

Holotype

ITALY • ♂; Veneto Region, Verona, Negrar, Val Borago , SW of Montecchio village; ~ 45.5188° N, 10.9816° E; 463 m a.s.l.; 8 Jan.–12 Feb. 2004; submesophilic meadow and common hornbeam ( Carpinus betulus ) deciduous forest, in the litter; pitfall traps; L. Reich leg.; MSNV.

Paratypes

ITALY – Veneto Region • 2 ♂♂; same collection data as for holotype; 12 Feb.–18 Mar. 2004; L. Reich leg.; MSNV • 1 ♂; Verona, Grezzana, Val Galina , Le Volpare; ~ 45.5229° N, 10.9916° E; 520 m a.s.l.; 28 Nov. 2003 – 8 Jan. 2004; submesophilic meadow, in the litter; pitfall traps; L. Reich leg.; MSNB • 1 ♂, 2 ♀♀; same locality as for preceding; 8 Jan.–12 Feb. 2004; L. Reich leg.; MSNB • 2 ♂♂, 1 ♀; same locality as for preceding; 12 Feb.–18 Mar. 2004; L. Reich leg.; MSNV • 1 ♂, 1 ♀; same locality as for preceding; 18 Mar.–28 Apr. 2004; L. Reich leg.; MSNB .

Other material

ITALY – Lombardia Region • 4 ♂♂, 1 ♀; Bergamo, Endine Gaiano , Lago di Gaiano ; 340 m a.s.l.; 2 Apr.–9 May 1996; pitfall traps; P. Pantini leg.; MSNB • 1 ♀; Bergamo, Solto Collina , San Defendente ; 670 m a.s.l.; 9 May–19 Jun. 1996; pitfall traps; P. Pantini leg.; MSNB. – Liguria Region • 1 ♂; La Spezia, Varese Ligure , Passo Cento Croci ; 1000 m a.s.l.; Sep. 1991 – May 1992; pitfall traps; G. Buttarelli, R. Cerbino, P. Pantini and M. Valle leg.; MSNB. – Veneto Region • 1 ♂; Padova, Teolo , Monte Venda ; 450 m a.s.l.; 8 Oct. 2002 – 27 Mar. 2003; Castanea sativa wood; pitfall traps; Museo BG staff leg.; MSNB • 5 ♀♀; Verona, Custoza , along Valle Molini road; 45.3727° N, 10.7909° E; 120 m a.s.l.; 29 Mar. 2010; in the litter; sieving; A. Sette leg.; MSNV • 1 ♀; Verona, Grezzana, Case Vecie ; 45.5243° N, 10.9989° E; 500 m a.s.l.; 16 May 1970; G. Osella leg.; MSNV • 2 ♂♂; Verona, Grezzana, SW of Guardini village; 250 m a.s.l.; 12 Feb.–18 Mar. 2004; uncultivated meadow with sparse arboreal vegetation, in the litter; pitfall traps; L. Reich leg.; MSNV • 1 ♀; Verona, Grezzana, Val Galina , Spigolo ; 290 m a.s.l.; 18 Mar.– 28 Apr. 2004; dry meadow, in the litter; pitfall traps; L. Reich leg.; MSNB • 1 ♂; Verona, Grezzana, Val Galina , Vajo dei Casotti ; 500 m a.s.l.; 28 Nov. 2003 – 8 Jan. 2004; deciduous forest; pitfall traps; L. Reich leg.; MSNB • 1 ♂; Verona, Grezzana, Val Galina , W of the “Cave di Pietra” locality; 175 m a.s.l.; 12 Feb.–18 Mar. 2004; mixed forest, in the litter; pitfall traps; L. Reich leg.; MSNV • 1 ♂, 3 ♀♀; Verona, Illasi , park of Villa Sagramoso Perez Pompei ; 45.4703° N, 11.1865° E; 195 m a.s.l.; 7 Apr. 2010; in the litter; sieving; A. Sette leg.; MSNV • 1 ♂, 4 ♀♀; same locality as for preceding; 45.4683° N, 11.1904° E; 230 m a.s.l.; 6 Mar. 2010; sieving; A. Sette leg.; MSNV • 1 ♀; Verona, Velo Veronese , Camposilvano , outside the Covolo di Camposilvano cave; 1180 m a.s.l.; 45.6256° N, 11.0911° E; 30 Aug. 2018; in the litter of a deciduous wood, sieving; F. Ballarin leg.; MSNV • 1 ♂; Vicenza, Castelgomberto ; 300 m a.s.l.; 8 Oct. 2002 – 27 Mar. 2003; Castanea sativa wood; pitfall traps; Museo BG staff leg.; MSNB • 1 ♀; Vicenza, Montecchio Maggiore ; 87 m a.s.l.; 2–8 Apr. 2018; forest; pitfall traps; D. Nardi leg.; MSNB • 1 ♂; Vicenza, Montecchio Maggiore , Monte Nero ; 4–14 Feb. 2019; pitfall traps; D. Nardi leg.; MSNB • 1 ♀; Vicenza, Schio , San Rocco ; 650 m a.s.l.; 8 Oct. 2002 – 27 Mar. 2003; beechwood; pitfall traps; Museo BG staff leg.; MSNB. – Emilia-Romagna Region • 19 ♂♂; Piacenza, Bobbio , near Passo Penice; 1100 m a.s.l.; 19 Sep. 2001 – 20 Mar. 2002; forest; pitfall traps; P. Pantini leg.; MSNB • 8 ♂♂, 2 ♀♀; same locality as for preceding; 20 Mar.–26 Apr. 2002; P. Pantini leg.; MSNB • 4 ♂♂, 2 ♀♀; same locality as for preceding; 26 Apr.–27 Jun. 2002; P. Pantini leg.; MSNB. – Lazio Region • 1 ♀; Roma, Canale Monterano , Guallo ; 179 m a.s.l.; 16 Mar.–18 Apr. 2007; in the litter; pitfall traps; V. Rizzo and A. Vigna Taglianti leg.; MSNV • 1 ♂; same locality as for preceding; 15 Jan.–15 Feb. 2008; V. Rizzo and A. Vigna Taglianti leg.; MSNV • 1 ♂; Roma, Canale Monterano , Mola Ceccarelli ; 250 m a.s.l.; 14 Dec. 2007 – 15 Jan. 2008; beechwood, in the litter; pitfall traps; V. Rizzo and A. Vigna Taglianti leg.; MSNV • 1 ♂; same locality; 15 Jan.–15 Feb. 2008; V. Rizzo and A. Vigna Taglianti leg.; MSNV • 1 ♂, 1 ♀; Roma, Canale Monterano , Regional Natural Reserve of Monterano , Diosilla ; 42.1313° N, 12.0902° E; 255 m a.s.l.; 15 Jan.–15 Feb. 2008; deciduous forest with black alder ( Alnus glutinosa ) and hornbeam ( Carpinus betulus ), in the litter; pitfall traps; V. Rizzo and A. Vigna Taglianti leg.; MSNV. – Marche Region • 1 ♀; Macerata, Visso , Monte La Bandita ; 1350 m a.s.l.; Jun.–Sep. 1992; pitfall traps; P. Pantini and M. Valle leg.; MSNB. – Umbria Region • 2 ♀♀; Perugia, San Giustino , Parnacciano ; 700 m a.s.l.; Jun.–Dec. 1991; pitfall traps; G. Buttarelli, E. Ghilardi, P. Pantini and M. Valle leg.; MSNB • 1 ♂; Perugia, Sigillo , near the village; 550 m a.s.l.; Jan.–Jun. 1991; pitfall traps; P. Pantini and M. Valle leg.; MSNB • 1 ♂, 1 ♀; Perugia, Sigillo , near Monte Cucco; 850 m a.s.l.; Jan.–Jun. 1992; pitfall traps; P. Pantini and M. Valle leg.; MSNB. – Abruzzo Region • 2 ♂♂, 2 ♀♀; Teramo, Torricella Sicura , Monti della Laga , 1 km from Santo Stefano village heading to Rocca Santa Maria; 7 Nov. 2002; O. Marotta and A.M. Zuppa leg.; MSNB. – Basilicata Region • 2 ♂♂, 1 ♀; Potenza, San Severino Lucano , near Santuario; 1500 m a.s.l.; Jun. 1990 – Jun. 1991; pitfall traps; G. Buttarelli, E. Ghilardi, P. Pantini and M. Valle leg.; MSNB.

Description

Male

HABITUS. See Fig. 1H.

MEASUREMENTS. Total length 1.69–2.25. Carapace 1.01 long, 0.78 wide.

PROSOMA. Carapace uniformly yellowish-brown; chelicerae, labium and gnathocoxae of the same colour. Chelicera with stridulatory ridges on the lateral margin. Three teeth at the anterior margin of the fang groove, posterior margin with 4–5 small denticles. Sternum greyish. Paler, yellowish coloration in some specimens.

ABDOMEN. Covered with sparse setae, uniformly greyish with lighter marks barely visible on the dorsal side, distal end with a lighter area.

LEGS. Uniformly yellowish-brown. Femur I with 1 prolateral spine. Tibial spine formula: 2221. TmI: 0.25. Leg measurements as follows: I: 0.77 + 0.27 +0.73 +0.58 +0.41 (2.77), II: 0.70 +0.27 + 0.65 +0.55 +0.39 (2.55), III: 0.61 + 0.23 +0.49 +0.52 +0.33 (2.18), IV: 0.82 +0.28 +0.78 +0.66 +0.40 (2.94).

PALP ( Figs 1 A–D, 2A–C). Patella and tibia bearing 1 robust spine each, tibia with 3 trichobothria. Cymbium with a massive, triangular dorsal hump facing backward followed by a large and stumpy median tubercle. Paracymbium large, bearing several short setae on the basal area, lateral margin covered with several minute wrinkles. Two proximal radical apophyses: radical apophysis I short, robust and spine-like; radical apophysis II long, thin and thread-like, curved outward and downward. Distal radical apophysis bearing one or several robust teeth. Distal suprategular apophysis robust and curved, with a second branch more or less strongly developed depending on the population and individual. Antero-proximal part of median membrane with a row of 8–10 stumpy teeth. Terminal apophysis clearly visible, ending with a wide, wrinkled tip. Embolus curved, ending in a sharp point.

Female

HABITUS. See Fig. 1I.

MEASUREMENTS. Total length 1.87–2.15. Carapace 0.81 long, 0.58 wide.

PROSOMA AND ABDOMEN. As in male. Abdomen usually darker, with marks more visible than in the male.

LEGS. As in male. Leg measurements as follows: I: 0.62 +0.30 +0.60 +0.43 +0.41 (2.35), II: 0.61 + 0.26 + 0.50 + 0.44 + 0.35 (2.17), III: 0.59 + 0.22 + 0.45 + 0.42 + 0.35 (2.03), IV: 0.74 +0.26 + 0.67 +0.54 +0.37 (2.58).

EPIGYNE AND VULVA ( Figs 1 E–G, 2D–E). Anterior wall triangular, strongly wrinkled, covering a large epigynal cavity, ending with a truncated tip and lacking a clear ending lobe. Distal part of scapus wide, lobate, strongly protruding from the epigynal cavity. Posterior median plate small and rectangular, longer than wide. Spermathecae elongated and S-shaped. Copulatory grooves first turning posteriorly and outward before returning to the middle part of the vulva and ending in copulatory openings in the distal part of the scapus.

Distribution

Endemic to Italy. Distributed along the Alpine and Apennine mountain ranges, from the Lessini Mountain Prealps to the Aspromonte massif, see Fig. 10 .

Figures

Fig. 1. Centromerus tongiorgii sp. nov., from Grezzana. A. Male palp, retrolateral view. B. Ditto, prolateral view. C. Ditto, ventral view. D. Ditto, dorsal view. E. Epigyne, ventral view, F. Ditto, lateral view. G. Vulva after maceration, dorsal view. H. Male habitus. I. Female habitus.

Fig. 2. Centromerus tongiorgii sp. nov., from Endine Gaiano. A. Male palp, retrolateral view. B. Ditto, prolateral view. C. Ditto, ventral view. D. Epigyne, ventral view. E. Vulva, dorsal view.

Fig. 10. Distribution in the Italian peninsula of the species C. tongiorgii sp. nov. (= red dots); C. hanseni sp. nov. (= azuretriangles); C. gatoi sp. nov. (= yellow diamonds); C. cf. paradoxus (Simon, 1884) (= green pentagons); C. desmetiBosmans, 1986 (= violetstar); C. succinus (Simon, 1884) (= dark bluesquares).

Fig. 3. Centromerus hanseni sp. nov., from Trifoglietti Lake. A. Male palp, retrolateral view. B. Ditto, prolateral view. C. Ditto, ventral view. D. Ditto, dorsal view. E. Epigyne, ventral view. F. Ditto, lateral view. G. Vulva after maceration, dorsal view. H. Male habitus. I. Female habitus.

Fig. 4. Centromerus hanseni sp. nov., from Trifoglietti Lake. A. Male palp, retrolateral view. B. Ditto, prolateral view. C. Ditto, ventral view. D. Epigyne, ventral view. E. Vulva, dorsal view.