Nemesia almoravida, Zonstein, 2019

Zonstein, Sergei L., 2019, New data on the spider genus Nemesia in Algeria (Araneae: Nemesiidae), Israel Journal of Entomology (Oxford, England) 49 (1), pp. 69-130 : 82-88

Nemesia almoravida n. sp.

( Figs 32–48)

LSID: urn:lsid:zoobank.org:act:A0971620-09D2-408B-AEB7-175CD24671AB .

Etymology: The species name is a Latinized adjective referring to the period of the medieval Maghreb (a part of North Africa, including Algeria) under the authority of the Almoravid dYnastY (XII–XIII centuries CE).

Diagnosis: Due to the presence of the retroventral preening combs on metatarsi IV, the new species appears to be similar to N. dido n. sp., N. tanit n. sp. and to several South European species related to N. bristowei (see the diagnosis of the previously listed species). However, representatives of N. almoravida n. sp. differ from all these species in possessing normally developed (i.e., not reduced) PMS. A peculiar shape of the bent and curved embolus distinguishes N. almoravida n. sp. from the congeners that possess comparable long emboli: N. decaei n. sp. and two undescribed Tunisian species ( Figs 37–39 cf. Figs 72, 73, 148–150). In addition, the only known male of N. almoravida n. sp. has only one dorsodistal spine on the palpal tibia ( Fig. 40), while males of other Nemesia species usually possess 3–4 or even more similarly located spines. Females of N. almoravida n. sp. resemble those of N. didieri in possessing the similarly shaped/arranged eye group, spinnerets and spermathecae. They differ, however, in details of ornamentation on the dorsal abdomen ( Figs 42 and 90), proportions of the sternum (wider in N. didieri ; Fig. 45 cf. Fig. 94) and in the structure of the spermathecae (with shorter stalks in N. almoravida n. sp. vs. longer ones in N. didieri ; Fig. 46, 47 cf. Fig. 94).

Description: Male (holotype MNHN 6896; Fig. 32): Body length 10.55.

Colour in alcohol: carapace dull brownish orange (darker stellate pattern of carapace almost faded); chelicerae light brownish red; eye tubercle brownish black; palpal and leg segments medium to pale yellowish orange; sternum, labium, maxillae, and leg coxae light brownish yellow; ventral surface of abdomen and spinnerets very pale brownish yellow; dorsal abdomen with faded brown pattern consisting of large vague spot in anterior part and several pairs of weak and diffuse chevrons posteriorly.

Cephalothorax dorsally and ventrally as in Figs 33 and 35, respectively. Carapace 4.43 long, 3.62 wide. Eye tubercle as in Fig. 34. Eye diameters and interdistances: AME 0.14(0.21), ALE 0.22, PLE 0.19, PME 0.12, AME–AME 0.13(0.06), ALE– AME 0.10(0.06), ALE–PLE 0.06, PLE–PME 0.04, PME–PME 0.35. Chelicerae: each furrow with 6 promarginal teeth and about 15 mesobasal denticles; rastellum with 6 heavy and about 10 smaller cone teeth in front of cheliceral fang. Labium 0.41 long, 0.92 wide. Sternum 2.23 long, 1.92 wide. Each maxilla with 2–3 thin rod-like cuspules confined to inner maxillary heel.

Palp and leg structures. Tibia and metatarsus I as in Fig. 36. Spines (tarsi I–IV aspinose). Palp: femur d1–1–2; patella p1; tibia with only one short dorsoapical spine; cymbium with about 12 short dorsal spines. Leg I: femur d1–1–1–1–2, pd1–1–1, rd1–1–1; patella p1–1; tibia p1–1, r1–1, pv1–1–M; rv1–1–1; metatarsus p1–1–1, r1–1–1, v1–1–2. Leg II: femur d1–1–1–1–2, pd1–1–1, rd1–1–1; patella p1–1, r1; tibia p1–1, r0–1, v2–2–3; metatarsus d1–1, p1–1–1, r1–1–1, v2–2(1)– 1(0)–3. Leg III: femur d 1–1–1–1–2, pd1–1–1, rd1–1–1; patella p1(0)–1–1, r1(0); tibia d2–1–0, p1–1, r1–1, v2–2–3; metatarsus d1–1, p1–1–1, r1–1–1, v2–2–3; Leg IV: femur d 1–1–1–1–2, pd1–1–1, rd1–1–1; patella r1; tibia p1–1–1, r2–1–1, v3(2)–2–3; metatarsus d1–1, p1–1–1, r1–1–1, v2–2–3. Metatarsal preening comb present on apical retroventral edge of metatarsus IV. Scopula entire and distal on metatarsi I and II, entire on tarsus I, narrowly divided on tarsus II, elsewhere absent. Trichobothria: 2 rows of 9–10 in each row on tibiae, 10–11 on metatarsi, 10–14 on tarsi, 9 on cymbium. Paired claws on tarsi I–IV with 8–9 teeth on each margin.

Leg and palp measurements:

Palp I II III IV Femur 2.44 3.61 3.39 3.08 3.83 Patella 1.12 1.98 1.60 1.57 1.98 Tibia 1.68 2.23 2.12 2.04 3.99 Metatarsus – 2.49 2.45 2.83 3.95 Tarsus 0.85 1.84 1.49 1.76 2.01 Total 6.09 12.15 11.05 11.28 15.76

Copulatory organs. Palpal tibia moderately short, with single dorsoapical spine ( Figs 37, 40). Palpal organ with thin, curved and gradually tapering embolus ( Figs 38, 39).

Spinnerets as in Fig. 41. PMS: length 0.35; diameter 0.19. PLS: maximum diameter 0.47; length of basal, medial and apical segments 0.79, 0.22, 0.11, respectively; total length 1.12; apical segment domed.

Female (paratype MNHN 12671/AR4428; Fig. 42): Body length 16.10.

Colour in alcohol: carapace, chelicerae, palps and legs medium brownish orange, with darker brown clypeus, H-shaped area on carapace and all femora; eye tubercle brownish black; sternum brownish yellow; labium, maxillae, leg coxae and PLS light brownish orange; most part of abdomen and PMS light brownish grey; darker dorsal abdominal pattern consisting of narrow median stripe fused with several paired lateral chevrons medium brown.

Cephalothorax dorsally and ventrally as in Figs 43 and 45, respectively. Carapace 6.24 long, 4.79 wide. Eye tubercle as in Fig. 44. Eye diameters and interdistances: AME 0.15(0.27), ALE 0.28, PLE 0.22, PME 0.14, AME–AME 0.22(0.10), ALE– AME 0.16(0.10), ALE–PLE 0.07, PLE–PME 0.03, PME–PME 0.52. Chelicerae: each furrow with 6 promarginal teeth and ca. 20 mesobasal denticles; rastellum: 4 large and about 15 smaller spines in front of cheliceral fang base. Labium 0.66 long, 1.14 wide. Sternum 3.43 long, 2.43 wide. Each maxilla with 2 or 3 cuspules confined to inner maxillary heel.

Palp and leg structures. Spines: femora I–IV dorsally with 6–7 very thin bristle-like spines; palpal tarsus and tarsi I and II each with 15–20 short and small ventroapical spines; patella IV and tarsi III–IV aspinose. Palp: femur d1–1–2, pd1; patella p1; tibia v2(1)–2–4; tarsus v2. Leg I: femur pd1, patella p2(0); tibia v1–1–1–2; metatarsus v2–1–3. Leg II: femur pd1; patella p1–1; tibia v1–1–3(2); metatarsus v2–1–3. Leg III: femur pd1–1–1, rd1–1–1; patella p1–1–1, r1; tibia p1–1, r1–1, v2–2–2; metatarsus d1, p1–1–1–1, r1–1–1, v2–2–3. Leg IV: femur rd1; tibia r1–1, v2–2(1)–2; metatarsus p1–1, v2–2–3. Metatarsal preening combs present on metatarsus IV (absent in some paratype females). Scopula entire on and distal on metatarsi I and II; narrowly divided on palpal tarsus and tarsus I; widely divided on tarsus II; elsewhere absent. Trichobothria: 2 rows of 10–11 in each row on tibiae, 14–15 on metatarsi, 13–16 on tarsi, 11 on palpal tarsus. Paired claws on tarsi I and II with 3–4/7–8 teeth in inner/outer rows, paired claws on tarsi III and IV with 3–4/6 and 2/4 teeth in these rows, respectively. Palpal claw with 3 teeth on promargin.

Leg and palp measurements:

Palp I II III IV Femur 2.91 4.04 3.75 3.18 4.26 Patella 1.62 2.52 2.37 1.87 3.19 Tibia 1.79 2.48 2.21 1.91 4.46 Metatarsus – 2.20 2.13 2.59 3.70 Tarsus 1.95 1.59 1.51 1.34 1.67 Total 8.27 12.83 11.97 10.89 17.28

Copulatory organs. Spermathecae relatively long, gently twisted and tapered, with only slightly dilated heads ( Figs 46, 47).

Spinnerets as in Fig. 48. PMS: length 0.56; diameter 0.35. PLS: maximum diameter 0.75; length of basal, medial and apical segments 0.96, 0.34, 0.17, respectively; total length 1.47; apical segment domed.

Variation: Carapace length in females varies from 5.8 to 6.2 mm.

Holotype: ♂ Algeria: Algiers Province: surroundings of Algiers (36°45′N 03°33′E), no other data (MNHN 6896).

Paratypes: Algeria: Blida Province: 1♀, Chiffa (labelled as ” La Choffa ”; 36°28′N 2°45′E), iv.1882, E. Simon (MNHN 2190/AR4446) ; 3♀, same localitY (labelled as ”La Chiffa”), iv.1882, E. Simon (MNHN 12671/AR4428).

Distribution: Known only from the surrounding of Algiers.