Messapus tigris, Haddad, Charles R. & Mbo, Zingisile, 2015

Haddad, Charles R. & Mbo, Zingisile, 2015, Five new species of the Afrotropical dark sac spider genus Messapus Simon, 1898 (Araneae: Corinnidae), Zootaxa 4057 (3), pp. 385-398 : 395

Messapus tigris sp. n.

Figs 1–3, 8 , 23–31 , 35 , 49, 50

Type material. Holotype ♀: NAMIBIA: Caprivi strip, 34 km East of Divungu, 18°02.944'S, 21°54.611'E, leg. C. Haddad, 30.XI.2006 (under bark) (NCA 2007/916).

Paratypes: BOTSWANA: Okavango Delta, Near Shakawe, Lesideng Research Camp, 18°25.822'S, 21°53.771'E, leg. L. van As, XII.2008 (in house), 1♀ (NCA 2014/1774); Same locality, leg. C. Haddad, 26– 29.XI.2006 (night collecting), 1♀ (NCA 2014/1775); Same locality, leg. C. Haddad, 11.XII.2006 (pitfall traps, riverine forest), 1♀ (NCA 2014/1775).

Etymology. The species name is taken from the Latin tigris (tiger), for the conspicuous bands on the legs.

Diagnosis. Females are easily recognized by the broad epigyne with two oblique incomplete oval ridges directed posterolaterally, which differs from M. megae sp. n. and M. natalis , in which they are orientated anterolaterally. Males unknown.

Female (holotype, Caprivi Strip, NCA 2007/916). Measurements: CL 3.78, CW 3.20, AL 5.75, AW 4.10, TL 9.90, FL 0.45, SL 1.90, SW 1.95, CH 0.15, AME–AME 0.14, AME–ALE 0.03, ALE–ALE 0.67, PME–PME 0.26, PME–PLE 0.17, PLE–PLE 0.96, PERW 1.25, MOQAW 0.62, MOQPW 0.66, MOQL 0.68.

Length of leg segments (sequence from femur to tarsus, and total): I 3.39 + 1.75 + 2.65 + 2.43 + 1.25 = 11.47; II 2.98 + 1.50 + 2.16 + 2.23 + 1.15 = 10.02; III 2.75 + 1.35 + 2.05 + 2.40 + 1.05 = 9.60; IV 4.00 + 1.60 + 3.25 + 3.80 + 1.35 = 14.00.

General appearance as in Figs 1, 2 , 8 . Carapace orange-brown medially, yellow-brown laterally, with broad black median stripe, absent along midline behind PER, around fovea to posterior margin; narrow pale oblique streak behind PLE; black lateral spots at coxae I–III; markings covered with black SSB, area between median eyes and areas without markings covered in silver-white SSB. All eyes surrounded by black rings; clypeus height equal to distance 0.63 times AME diameter; AER slightly procurved; AME slightly larger than ALE; AME separated by distance 0.60 times their diameter; AME separated from ALE by distance 0.13 times AME diameter; PER slightly procurved; PME slightly larger than PLE; PME separated by distance 1.18 times their diameter; PME separated from PLE by distance 0.79 times PME diameter. Chelicerae deep orange-brown, with several longitudinal black streaks; long black setae on paturon; CPPM present; promargin with three teeth, proximal tooth largest, distal tooth smallest; retromargin with five teeth, proximal tooth large, slightly separated from second tooth, remaining teeth smaller and adjacent, decreasing slightly in size distally. Endites yellow-brown, cream distally, with distinct serrula; labium slightly broader than long, yellow-brown, yellow distally; sternum shield-shaped, broader than long, cream-yellow, darker around margins, without markings, with scattered short straight setae. Legs creamyyellow, with black markings comprising SSB; femora with broad black band in distal half, small black mottled markings in proximal half; patellae with black band in proximal two-thirds; tibiae and metatarsi with broad black band, absent at proximal and distal ends; tarsi black with orange tips. Leg spination: femora: I pl 1 do 2, II pl 1 do 2, III pl 2 do 3 rl 2, IV do 1-3 rl 1-2; tibiae: I plv 3 rlv 3, II spineless, III pl 2 rl 2 plv 2 rlv 1 vt 2, IV pl 2 rl 2 plv 2 vt 2; metatarsi: I plv 2 rlv 2 vt 3, II plv 2 rlv 2 vt 2, III pl 1 rl 1 plv 1 rlv 2 vt 3, IV pl 1 rl 2 plv 2 rlv 2 vt 3. Palpal spination: femora: pl 1 do 2; patellae: pl 1 spine do 2 thickened setae; tibiae: pl 3; tarsi: pl 1 plv 1. Dorsum and sides of abdomen covered in black SSB, with scattered tiny patches of cream SSB; venter creamy-grey, covered in creamy-brown SSB and scattered short straight brown setae, with scattered small patches of black SSB. Epigyne broad, with two oblique oval ridges directed anterolaterally, with copulatory openings in anterior corner of ridges ( Figs 35 , 49 ); ST massive, suboval, situated laterally, with small anterior lobe ( Fig. 50 ).

Distribution. Known only from two localities in Botswana and Namibia ( Fig. 55 ).

Figures

FIGURE 55. Distribution of Messapus megae sp. n. (black circle), M. meridionalis sp. n. (black star), M. seiugatus sp. n. (black square), M. tigris sp. n. (open circles) and M. tropicus sp. n. (open squares) in the Afrotropical Region.

FIGURES 1 – 2. Habitus photographs of female Messapus tigris sp. n. from Okavango Delta in Botswana: 1 Hiding in a crevice on Vachellia tortilis bark; 2 On the soil surface. Photographs by C. Haddad.

FIGURES 3 – 10. Digital microscope photographs of Messapus species, female right chelicerae in posterior view (3) and dorsal habitus (4 – 10): 3, 8 M. tigris sp. n., female; 4 M. megae sp. n., female; 5 Same, male; 6 M. meridionalis sp. n., female; 7 M. seiugatus sp. n., female; 9 M. tropicus sp. n., female; 10 Same, male. Scale bars: 3 = 1 mm, 4 – 10 = 2 mm. Abbreviations: CPPM—cheliceral promarginal pronounced mound; F—fang; P—paturon; PMT—promarginal teeth; RMT—retromarginal teeth.

FIGURES 23 – 31. Scanning electron micrographs of Messapus tigris sp. n. female, leg III: 23 Femur, spine, elongate striate scales (ESS) and squamose setae with brachia (SSB); 24 Patella, SSB, ESS and rugose longitudinal dorsal lines (RL); 25 Tibia, spine, SSB and ESS; 26 Metatarsus, SSB and ESS; 27 Distal part of tarsus, indicating trichobothriae (TR), tarsal pores (TP), tarsal slit sensillum (TS), tactile setae (TaS) and chemosensory seta (CS); note the much longer brachia and narrower shafts of the SSB in this part of tarsus; 28 Tarsal claw; 29 Proximal tarsal trichobothrium; 30 Tarsal pore; 31 Tarsal slit sensillum.

FIGURES 32 – 40. Digital microscope photographs of Messapus species, cleared female epigynes in ventral view (32 – 36) and male palps in ventral (37, 39) and retrolateral views (38, 40): 32, 37, 38 M. megae sp. n.; 33 M. meridionalis sp. n.; 34 M. seiugatus sp. n.; 35 M. tigris sp. n.; 36, 39, 40 M. tropicus sp. n.. Scale bars: 0.5 mm.

FIGURES 45 – 50. Female genitalic morphology of Messapus meridionalis sp. n. (45, 46), M. seiugatus sp. n. (47, 48) and M. tigris sp. n. (49, 50): 45, 47, 49 Epigyne, ventral view; 46, 48, 50 Same, dorsal view. Scale bars: 0.5 mm.