Messapus megae, 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 : 390-393

Messapus megae sp. n.

Figs 4, 5 , 32, 37, 38 , 41–44

Type material. Holotype ♀: ZIMBABWE: Harare, Highlands, Walmer drive, 17°49'S, 31°05'E, leg. M. Cumming, 28.V.1999 (in tree) (NCA 2014/1857).

Paratype: Same data as holotype, 1♂ (NCA 2014/1858).

Etymology. Named after the collector of the type specimens, Meg Cumming.

Diagnosis. Messapus megae sp. n. can be recognised by the females having oblique-oval epigynal ridges that are posterolaterally situated and two spermathecae that are widely separated and anteriorly positioned in the epigyne ( Figs 32 , 41 ). Males have a very distinctive palp, with a long embolus originating prolaterally, curving distally and ending medially along the retrolateral margin of the tegulum. They also possess a characteristic very fine, weakly sclerotised prolateral conductor, and a very long narrow RTA ( Figs 37 , 43 ).

Female (holotype, Harare, NCA 2014/1857). Measurements: CL 2.85, CW 2.65, AL 4.45, AW 2.85, TL 7.10, FL 0.25, SL 1.45, SW 1.69, CH 0.08, AME–AME 0.10, AME–ALE 0.03, ALE–ALE 0.56, PME–PME 0.15, PME–PLE 0.14, PLE–PLE 0.76, PERW 0.98, MOQAW 0.52, MOQPW 0.51, MOQL 0.54.

Length of leg segments (sequence from femur to tarsus, and total): I 2.75 + 1.25 + 2.05 + 1.92 + 1.17 = 9.14; II 2.55 + 1.10 + 1.80 + 1.78 + 1.05 = 8.28; III 2.50 + 1.00 + 1.75 + 2.08 + 1.15 = 8.48; IV 2.90 + 1.10 + 2.30 + 2.50 + 1.20 = 10.00.

General appearance as in Fig. 4 . Carapace yellow-brown, paler laterally, with broad mediolateral black markings, black marking in front of fovea; markings covered in black FS, silver-white FS between them. All eyes surrounded by black rings; clypeus height equal to distance 0.37 times AME diameter; AER slightly procurved; AME larger than ALE; AME separated by distance 0.44 times their diameter; AME separated from ALE by distance 0.15 times AME diameter; PER slightly procurved; PME slightly larger than PLE; PME separated by distance 0.86 times their diameter; PME separated from PLE by distance 0.82 times PME diameter. Chelicerae orange-brown with black mottled markings, with dark brown setae on paturon; CPPM present; promargin with three teeth, median tooth largest, slightly larger than proximal tooth, distal tooth tiny, median and distal teeth closest together; retromargin with four teeth, proximal largest, separate from remaining teeth that are adjacent, decreasing in size distally. Endites creamy-brown, cream distally; serrula distinct; labium yellow-brown, cream distally; sternum shield-shaped, broader than long, cream, with scattered straight brown setae. Legs creamy-yellow, distal segments slightly darker; markings covered in black FS; femora with broad black band at 2/3 their length, scattered small black spots in proximal half; patellae with lateral black marking, proximal median stripe; tibiae with broad median black band; metatarsi with proximal black band, faint narrow distal ring; tarsi without markings. Leg spination: femora: I pl 1 do 3, II pl 2 do 2 rl 1, III pl 2 do 1 rl 2, IV do 1 rl 1; tibiae: I plv 2 rlv 1, II and III spineless, IV plv 1; metatarsi: I plv 2 rlv 2 vt 2, II spineless, III vt 2, IV vt 2. Palpal spination: femora: pl 1 do 2; patellae: do 1; tibiae: pl 3 plv 2. Abdomen cream dorsally and laterally, with black patches anteriorly and chevrons in posterior half; markings covered in black FS, silver-white FS between them; venter cream, covered in short straight brown setae and cream FS. Epigyne with slightly separated posterolaterally situated oblique-oval epigynal ridges ( Figs 32 , 41 ); copulatory openings entering spermathecae posteromedially; spermathecae widely separated and positioned anterolaterally in epigyne ( Fig. 42 ).

Male (paratype, Harare, NCA 2014/1858). Measurements: CL 2.79, CW 2.43, AL 4.30, AW 2.40, TL 7.05, FL 0.11, SL 1.37, SW 1.49, CH 0.11, AME–AME 0.13, AME–ALE 0.02, ALE–ALE 0.49, PME–PME 0.13, PME–PLE 0.09, PLE–PLE 0.63, PERW 0.87, MOQAW 0.50, MOQPW 0.47, MOQL 0.54.

Length of leg segments (sequence from femur to tarsus, and total): I 2.92 + 1.10 + 2.28 + 2.55 + 1.35 = 10.20; II 2.60 + 1.00 + 1.90 + 1.85 + 1.20 = 8.55; III 2.55 + 1.02 + 1.92 + 2.10 + 1.25 = 8.84; IV 2.85 + 1.10 + 2.30 + 2.50 + 1.35 = 10.10.

General appearance as in Fig. 5 ; colouration, markings and cheliceral morphology as for female, except male slightly darker. Clypeus height equal to distance 0.48 times AME diameter; AER slightly procurved; AME larger than ALE; AME separated by distance 0.34 times their diameter; AME separated from ALE by distance 0.10 times AME diameter; PER slightly procurved; PME very slightly smaller than PLE; PME separated by distance 0.57 times their diameter; PME separated from PLE by distance 0.38 times PME diameter. Leg spination: femora: I pl 1 do 2, II pl 1 do 2, III pl 2 do 1 rl 2, IV pl 1 do 1; tibiae: I plv 2 rlv 1, II spineless, III plv 1, IV plv 1; metatarsi: I plv 2 rlv 2 vt 2, II spineless, III vt 2, IV vt 2. Palpal spination: femora: pl 1 do 1; patellae: pl 1; tibiae: pl 1 plv 1. Abdomen with yellow-brown anterior scutum extending abdomen length. Palps yellow-brown, embolus long, originating prolaterally, curving distally in broad arc, ending medially along retrolateral margin of tegulum, distal end forming a loop; conductor very fine, weakly sclerotised, situated prolaterally at embolus base, extending approximately 1/3 of embolus length ( Figs 37 , 43 ); RTA very long and narrow, slightly curved in retrolateral view ( Figs 38 , 44 ).

Distribution. Known only from the type locality ( 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 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 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 41 – 44. Genitalic morphology of Messapus megae sp. n.: 41 Female epigyne, ventral view; 42 Same, dorsal view; 43 Male palp, ventral view; 44 Same, retrolateral view. Scale bars: 0.5 mm.