Nemesia apenninica, Decae, Arthur, Pantini, Paolo & Isaia, Marco, 2015

Decae, Arthur, Pantini, Paolo & Isaia, Marco, 2015, A new species-complex within the trapdoor spider genus Nemesia Audouin 1826 distributed in northern and central Italy, with descriptions of three new species (Araneae, Mygalomorphae, Nemesiidae), Zootaxa 4059 (3), pp. 525-540 : 528-532

Nemesia apenninica n. sp.

( Figs 4 A, B, 5)

Type material. ITALY: Lombardia: Holotype: nr. NHMB.186, 1(m), Province of Pavia, loc. Retorbido, Murisasco, 44.93°N, 9.07°E, alt. 400m, oak wood, leg. Gentilli, Lodovici & Pantini, 19.X.2011, MCSNB.

Paratypes: ITALY: Lombardia: nr. NHMB.187 1(f). loc. as holotype; nrs NHMB.188, 1(m), and NHMB.189, 1(f), loc. Rocca de’ Giorgi, 44.97°N, 9.25°E, alt. 260m, oak wood, leg. Gentilli, Lodovici & Pantini, 19.X.2011, MCSNB.

Other material examined. ITALY: Lombardia: Province of Pavia, Retorbido, loc. Murisasco, 44.93°N, 9.07°E, alt. 400 m, oak wood, leg. Pantini P., 4(f) 4(j), 1.X.2012, (pt), MCSNB. Liguria: Province of Genova, Montoggio, Fontana Fredda Superiore, 44.51°N, 9.06°E, alt. 500 m, leg. Raineri & Valle, 1(m), 2.XI.2001, NHMR. Emilia-Romagna: Province of Bologna, Imola, Riserva Naturale Bosco della Frattona, 44.35°N, 11.66°E, alt. 80 m, wood, leg. Fabbri, 6(m) 4(j), 13.X–20.XI.2000 (pt), MCSNB; Province of Forlì-Cesena, Premilcuore, Parco Nazionale Foreste Casentinesi, Poggio Cavallaro, 44.18°N, 12.15°E, alt. 720–750 m, leg. Fabbri, 1(m), 19.IX– 29.X.2001 (pt), MCSNB; Meldola, Riserva Naturale Bosco di Scardavilla, alt. 80–120 m, 44.14°N, 12.04°E, wood, leg. Fabbri, 6(m) 5(j), 17.X–18.XI.1998 (pt), NHMR. Toscana: Province of Massa-e-Carrara, Massa, Monte di Pasta, 44.03°N, 10.14°E, leg. Rossi, 1(m), 15.X.2012; 1(f), 20.X.2012, MCSNB.

Diagnosis ( Fig. 5 ). Males differ from other species in the Nemesia apenninica group by the twisting of the embolus starting in the proximal half of the segment ( Fig. 5 A), the strong sigmoid curvature of the embolus best seen in ventral and dorsal view ( Fig. 5 A, B), the sharply narrowing dorsal embolus tip best seen in retrolateral view ( Fig. 5 C), and the distinct narrow proximal origin of the embolus from the central globular part of the bulb best seen in prolateral view ( Fig. 5 D). Spermathecae composed of two slender, centrally twisted receptacles without any conspicuous narrowing or widening ( Fig. 5 E).

Description. Male holotype. Measurements: BL=13.8, CL=5.3, CW=4.3, Ca=3.2, Pa=6.3, L1=13.9, L2=13.3, L3=13.0, L4=18.1. Carapace ( Fig. 4 B): shape slightly more compact than in other species in apenninica group (CL/CW=1.2, CL/Ca=1.7), fovea deep, recurved crescent shaped with distinct central longitudinal groove, clypeus yellow with few distally oriented bristles, narrow, ca. 0.5x length of eye-group, longitudinal row of fine bristles on cephalic crest, irregular groups of bristles around eyes and on caudal thorax, strong pro-curved bristles along posterior edges of carapace, lighter recurved bristles along anterior edges, pubescence cover indistinct, eye-group slightly shorter than in other species of the apenninica group (l/w=1.5), lateral eyes larger than median, ALE slightly larger than PLEs (ALE/PLE=1.1), AER slightly shorter than PER (AER/PER=0.98), light patch between ALEs, POP uniform black. Chelicerae: dorsally uniform warm brown, strongly contrasting with color of carapace, glabrous longitudinal zone over surface bordered on both sides by groups of strong bristles that distally merge with rastellum, ventrally light brown, cheliceral furrow prolateral lined with six conical teeth, retrolateral with dense pinkish scopula, fang sharp, regularly curves with smooth, non-serrated ventral keel, rastellum of few strong teeth placed directly above fang insertion. Maxillae: (l/w=1.7), brown, darker than ventral leg coxae, white anterior edge with dense pinkish scopula, proximal heel rounded, distal anterior process pronounced, ventral surface of segment evenly covered with black bristles, cuspules and serrula absent. Labium: (l/w=0.5), same color as ventral maxillae, separated from sternum by wide glabrous labial furrow, anterior edge concave, curved bristles evenly spread over ventral surface. Sternum: (l/w=1.3) yellowish brown with slightly darker edge, posterior projecting narrow lobe between coxae IV, widest between coxae II, III, evenly set with black bristles, fine hairs along outer edges, weak notch opposite posterior sigilla, sigilla rounded, in three sub-marginal pairs (opposite coxae I, II and III), anterior two pairs small, posterior pair larger. Legs: three distal segments elongated, dorsal femora darker than other segments, further uniform color, prolateral spines on all patellae, retrolateral spines on patellae III, IV, dense cover of dark grey pubescence on all dorsal femora, scopulae present on tarsi and metatarsi of legs I and II, less developed than in females, scopula on ventral metatarsus I modified with dense group of fine spiky hairs, tibia I distally enlarged forming clasping organ with strong curved hook originating from cuticular spur, STC with strongly developed double combs of fine teeth, inner combs on leg IV reduced, AC smooth, well developed on all tarsi. Palps: color and bristle pattern as in legs, tibia proximally inflated (l/w=1.8) with distinct rake of strong curved spines in two rows near dorsal apex, femur dorsally armed with series of distally directed spines in distal half, cymbium distally bi-lobed with series of short distally directed spines in distal half. Trichobothria: as in other Nemesia species, with irregular zigzag pattern on dorsal tarsus, compact distal group followed by a roughly straight longitudinal central dorsal row on metatarsi, and two roughly parallel distally slight diverging longitudinal rows on dorsal tibia, trichobothria on cymbium in compact central group. Palpal organ: see Fig. 5 A, D. Abdomen: dorsal pattern of lighter and darker blotches, ventrally light creamy white. Spinnerets: same color as ventral abdomen, PMS well developed, with numerous apical spigots, PLS three segmented, distal two segments shorter than basal segment, spigots evenly distributed on proximal and medial segment and apically on distal segment.

Female paratype. Measurements: BL=13.8, CL=5.4, CW=4.4, Ca=3.4, Pa=7.9, L1=11.7, L2=10.8, L3=10.5, L4=16.3. Carapace ( Fig. 4 A): shape slightly more compact than other two species (CL/CW=1.2, CL/Ca=1.6), cephalic part elevated with wide cone shaped light colored CZ gradually narrowing from eye-group to fovea and dark brown flanks, thoracic part as in male, bristles restricted to CZ and clypeus, pubescence indistinct, fovea somewhat irregular recurved, eyes-grouped relatively wide (l/w=1.5), light patch between ALEs, POP deep black connecting all eyes, ALE largest (ALE/PLE=1.7), AER as long as PER (AER/PER=1.00). Chelicerae: more robust than in males, dark brown with some lighter colored zones, darkly contrasting with carapace color, ventrally reddish brown, further as described for male. Maxillae: relatively short (l/w=1.5), with distinct proximal short rows of 5–6 cuspules. Labium: (l/w=0.6) with straight anterior edge further as in male. Sternum: (l/w=1.2) as in male. Legs: without distinct color patterns, almost uniform yellowish brown with slightly darker zones on dorsal femora and around more proximal joints between segments, all segments, except coxae and trochanters, dorsally covered with black bristles, ventrally, pro- and retro-laterally with finer hairs, dense cover of fine pubescent hairs in bristle fields on posterior two leg pairs, few spiny bristles dorsally on all femora. Spines: two strong spines in line on prolateral patella III, slender spines on lateral and ventral faces of all metatarsi and tibiae. Scopulae: dense on lateral and ventral faces of tarsi and metatarsi I & II, not extending on tibia, tiny spines in longitudinal rows within scopulae on ventral tarsi I and II. Palps: largely as legs, tarsi with dense ventral and lateral scopulae, ventral long and slender spines, single pro- and retrolateral proximal spines, single apical claw with single prolateral comb of fine teeth. Trichobothria, claws, abdomen pattern and spinnerets as in male. Abdomen: with dorsal pattern of irregular light and dark colored blotches, ventrally light grayish brown. Spermathecae ( Fig. 5 E): two simple, blindending, three-partite receptacles. The density of glandular tissue is high in twisted medial part of receptacles, moderate in proximal part and light in distal part. Distal, membranous, blindly ending part is slightly inflated.

Variation in type sample. Males (n=2): BL=12.3–13.8, CL=5.0–5.3, Pa=6.1–6.3, L1=13.5–13.9, L2=12.5– 13.3, L3=12.1–13.0, L4=17.6–18.1. Ratio ranges (n=2) CL/CW=1.2–1.3, CL/Ca=1.6–1.7, Eye-group l/w=1.5–1.6, ALE/PLE=1.1–1.7, AER/PER=1.0.

Females (n=2): BL=13.8–15.2, CL=5.3–5.4, Pa=7.6–7.9, L1=11.1–11.7, L2=10.1–10.8, L3=9.7–10.5, L4=14.6–16.3. Ratio ranges (n=2) CL/CW=1.2, CL/Ca=1.6, Eye-group l/w=1.3–1.5, ALE/PLE=1.5–1.7, AER/ PER=1.0.

Etymology. The species is named after its distribution range in the northern Apennine Mountains.

Figures

FIGURE 4. Broadly similar appearance of three Nemesia new species, described below, of the apenninica group: A, N. apenninica (f), CL = 5.4 mm; B, N. apenninica (m), CL = 5.3 mm; C, N. hastensis (f) CL = 5.3 mm; C, N. hastensis (m), CL = 4.7 mm; D, N. pedemontana (f), CL = 5.8 mm; E, N. pedemontana (m), CL = 4.3 mm. Variations in pigment patterns (although generally slightly darker in N. pedemontana), carapace shape seen here have only weak diagnostic value in Nemesia species level taxonomy.

FIGURE 5. Nemesia apenninica n. sp.: camera lucida drawings of right male palpal organ (A – D) and in dorsal view, female spermathecae (E). Asymmetrically shaped palpal organ shown under four rotation angles around longitudinal axis (ax). A = ventral, B = dorsal, C = retrolateral, D = prolateral, the spermathecae are drawn in ventral view.