Nemesia didieri Simon, 1892

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 : 100-105

Nemesia didieri Simon, 1892

( Figs 82–95)

Nemesia didieri Simon, 1892: 114 (♀); Reimoser 1919: 7; Roewer 1942: 181; Bonnet 1955: 1040.

Diagnosis: Females of N. didieri resemble those of N. almoravida n. sp. in possessing the similarly shaped/arranged eye group, spinnerets and spermathecae. However, they differ in details of ornamentation on the dorsal abdomen ( Figs 59 and 90), proportions of the sternum (wider in N. didieri ; Fig. 62 cf. Fig. 93) and in the structure of the spermathecae (shorter stalks in N. almoravida n. sp. vs. longer ones in N. didieri ; Figs 63, 64 cf. Fig. 94). The only known conspecific male differs from males of other Nemesia species by the structure of the palpal organ which displays a moderately long funnel-shaped embolus curved sideways ( Figs 87–89).

Redescription: Male (MNHN 797/AR4474; Fig. 82): Body length 9.10.

Colour in alcohol: carapace, femora and patellae I–IV dull yellowish orange; entire palp and other leg segments brownish yellow; clypeus medium brown; eye tubercle brownish black; chelicerae and palpal organs medium brownish orange; sternum, labium, maxillae, most part of abdomen and PLS light brownish yellow. Abdomen with brown dorsal pattern consisting of fairly discernible narrow median strip and several paired lateral chevrons located posteriorly.

Cephalothorax dorsally and ventrally as in Figs 83 and 85, respectively. Carapace 3.69 long, 2.88 wide. Eye tubercle as in Fig. 84. Eye diameters and interdistances: AME 0.13(0.18), ALE 0.28, PLE 0.16, PME 0.14, AME–AME 0.16(0.11), ALE– AME 0.08(0.06), ALE–PLE 0.03, PLE–PME 0.04, PME–PME 0.33. Chelicerae: each furrow with 6 promarginal teeth and about 15 mesobasal denticles; rastellum with 3 to 4 heavy cone teeth in front of cheliceral fang, and with a few smaller teeth in front of cone teeth row. Labium 0.38 long, 0.74 wide. Sternum 2.23 long, 1.67 wide. Maxillae without cuspules.

Palp and leg structures. Tibia and metatarsus I as in Fig. 86. Spines (palpal patella and tarsi I–IV aspinose). Palp: femur d1–1–2; tibia with 5 (4 apical and 1 subapical) dorsal spines; cymbium with 12(11) short dorsal spines. Leg I: femur d1–1–1–2, pd1; patella p1; tibia p1(0)–1, pv0–0–M; rv1–1–1; metatarsus pd1–1–1–2, pv1, r1–1, rv1–1–1–1. Leg II: femur d1–1–1–1–2, pd1–1–1, rd1–1–1; patella p1(0)–1; tibia p1–1, r1–1, v1–2–2; metatarsus pd1–1–1(2)–2, r1–1, v2–1–2. Leg III: femur d 1–1–1–1–2, pd1–1–1, rd1–1–1; patella p1–1, r1; tibia p1–1, r1–1, v2–1–3(2); metatarsus d1–1, p1–1–1–1, r1–1–1, v2(1)–2(1)–2. Leg IV: femur d 1–1–1–1–2, pd1–1–0, rd1–1–1–1; patella r1; tibia p1–1, r1–1, v2–1–3(2); metatarsus d1, pd1– 1–1, rd1–1–1, v2(0)–2(1)–3(2). Metatarsal preening combs absent. Scopula entire and distal on metatarsi I and II; entire on tarsi I and II; very sparse and mixed with setae on tarsi III and IV. Trichobothria: 2 rows of 8–9 in each row on tibiae, 12–14 on metatarsi, 13–15 on tarsi, 8–9 on cymbium. Paired claws on tarsi I–IV with 7–9 teeth in each row. Unpaired tarsal claw small and sharply curved.

Leg and palp measurements:

Palp

I II III IV

Femur 1.89 3.23 3.07 2.81 3.55

Patella 0.89 1.71 1.65 1.43 1.86

Tibia 1.50 2.18 2.12 1.94 3.50

Metatarsus – 2.37 2.31 2.60 3.31

Tarsus 0.78 1.77 1.63 1.62 1.55

Total 5.06 11.26 10.78 10.40 13.77

Copulatory organs. Palpal tibia moderately swollen with few dorsal spines ( Figs 87, 88). Embolus relatively short, tapering and slightly curved subapically ( Figs 87, 89).

Spinnerets. PMS: length 0.23; diameter 0.11. PLS: maximum diameter 0.34; length of basal, medial and apical segments 0.65, 0.22, 0.09, respectively; total length 0.96; apical segment domed.

Female (MNHN 797/AR4474; Fig. 90): Body length 13.05.

Colour in alcohol: as in male, with slightly darker and more contrast dorsal pattern on carapace and abdomen (clypeus otherwise somewhat lighter than in male).

Cephalothorax dorsally and ventrally as in Figs 91 and 93, respectively. Carapace 4.88 long, 3.59 wide. Eye tubercle as in Fig. 92. Eye diameters and interdistances: AME 0.15(0.21), ALE 0.23, PLE 0.18, PME 0.13, AME–AME 0.18(0.12), ALE– AME 0.12(0.09), ALE–PLE 0.07, PLE–PME 0.02, PME–PME 0.44. Chelicerae: each furrow with 6 promarginal teeth and about 20 mesobasal denticles. Rastellum: 4–5 strong and about 15 smaller spines in front of cheliceral fang base. Labium 0.45 long, 0.92 wide. Sternum 2.68 long, 1.94 wide. Each maxilla with 4 stout cuspules confined to inner maxillary heel.

Palp and leg structures. Spines: palpal patella, patella IV and tarsi III–IV aspinose. Palp: femur d1–1–2, pd1; tibia p1, v2–2–5; tarsus v1–1–2–2–2. Leg I: femur d1–1– 1–1–2, pd1, patella p1; tibia p1–1, v1–1–2; metatarsus v1–1–3; tarsus 1–1–2–2. Leg II: femur d1–1–1–1–2, pd1; patella p1; tibia p1–1, v1–1–2; metatarsus v1–1–3(4); tarsus: ca. v10 small in one row. Leg III: femur d1–1–1–1–2, pd1–1–1, rd1(0)–1–0; patella p1–1, r1–1; tibia p1–1, r1–1, v2–2–3; metatarsus p1–1–1, pd1–1–1, r1–1–1, v2–2(1)–3. Leg IV: femur d1–1–1–1–2, rd1(0)–1(0); tibia r1–1, v2–2–3; metatarsus p1–1–1, pd1–1, rd1–1–1–1, v2–2–1–3. Metatarsal preening combs absent. Scopula entire on and distal on metatarsi I and II; widely divided on palpal tarsus and tarsi I–II; elsewhere absent. Trichobothria: 2 rows of 9–11 in each row on tibiae, 11–14 on metatarsi, 12–14 on tarsi, 11 on palpal tarsus. Paired claws on tarsi I–III with 5–6 teeth in each row, on tarsus IV – with 2–3 teeth only in outer row (inner row absent). Palpal tarsal claw with 6 teeth on promargin.

Leg and palp measurements:

Palp I II III IV Femur 2.15 3.48 3.03 2.75 3.74 Patella 1.11 2.09 1.77 1.67 2.49 Tibia 1.48 2.21 1.78 1.57 3.94 Metatarsus – 1.85 1.80 2.07 3.45 Tarsus 1.69 1.18 1.15 1.33 1.58 Total 6.43 10.81 9.53 9.39 15.20

Copulatory organs. Spermathecae relatively long, gently twisted and tapered, with only slightly dilated heads ( Fig. 94).

Spinnerets as in Fig. 95. PMS: length 0.39; diameter 0.16. PLS: maximum diameter 0.49; length of basal, medial and apical segments 0.61, 0.22, 0.10, respectively; total length 0.93; apical segment domed.

Variation: Carapace length in females varies from 4.1–5.4 mm. Darker dorsal pattern of the abdomen in some paralectotypes appears to be bleached during storage.

Lectotype: ♀ (designated here) Algeria: M’Sila Province: Bou Saâda (« B. Sauda », as labelled; 35°13′N 4°10′E) and surroundings, no other data (MNHN 9954/AR4439).

Paralectotypes: Algeria: 2♀ (designated here), same collecting data and depositorY number as in holotYpe ; 4♀, same collecting data (MNHN 9954/AR4431).

Other material examined: Algeria: M’Sila Province: 1♂ 1♀ 2 juv., Bou Saâda 245 km S Algiers (« B. Saada », as labelled), no other data (MNHN 797/AR4474) .

Distribution: Known only from the type locality.