Myrmarachne ichneumon (Simon, 1886)

Wesolowska, Wanda & Haddad, Charles R., 2009, Jumping spiders (Araneae: Salticidae) of the Ndumo Game Reserve, Maputaland, South Africa, African Invertebrates 50 (1), pp. 13-103 : 58-60

Myrmarachne ichneumon (Simon, 1886)

Figs 105–110

Salticus ichneumon: Simon 1886: 387 ; Peckham & Peckham 1892: 17, pl. 1, fig. 7; 1903: 250.

Myrmarachne ichneumon: Simon 1901 c: 498 ; Roewer 1965: 47, figs 38, 38a; Wanless 1978 b: 56, figs 31a–g,

32a–i.

Redescription:

Measurements (male/female): Carapace length 2.4–2.8/2.3, width 1.2–1.3/1.2, height 0.9/0.9. Abdomen length 3.5–3.8/3.3, width 0.8–0.9/1.0. Eye field length 0.8–1.0/0.8, anterior width 0.8–0.9/0.8, posterior width 1.0–1.1/0.9.

Male.

Body very elongate and slender ( Fig. 105). Carapace orange, eyes with black rings, eye field with silver patch of translucent guanine crystals and pair of darker spots in centre; delicate hairs sparsely cover carapace, some whitish hairs in constriction furrow. Mouthparts orange, clypeus clothed in white hairs; chelicerae very long and slender, fang with small protuberance, 14 teeth on promarginal edge and 12 on retromarginal edge ( Fig. 106); dark line along dorsal inner margins of chelicerae. Abdomen long, thin, orange greyish, with pair of darker spots in midway of posterior dorsal scutum; spinnerets yellow. Legs yellowish, femora slightly darker, tarsus of first pair brownish. One specimen dark, almost black, abdomen shiny; only legs light, yellowish, with dark lines along sides of segments and femora tinged with grey. Pedipalps orange; tibial apophysis distally hooked, with well developed flange, protected by depression in cymbium and tuft of long bristles on proximal edge of cymbium ( Figs 107, 108).

Female.

Shape of body similar to male, but abdomen slightly wider and chelicerae shorter. General colouration orange yellowish, rings surrounding eyes black; silver spots of guanine crystals translucent through integument. Epigyne in Fig. 109, with two large openings separated by septum and smaller paired posteromedian pouches; seminal ducts long, their initial parts membranous and poorly visible, receptacles looped ( Fig. 110).

Material examined: 1ơ Crocodile Farm, 26 ° 54.426'S: 32 ° 19.185'E, broadleaf woodland, beats, short shrubs, 14.xii.2000 ( NCA 2008 /2741); 1ơ Near Vulture Restaurant, 26 ° 53.376'S: 32 ° 18.703'E, subtropical bush, on bush, 7.vii.2000 ( NMSA 21864 ) ; 1^Red Cliffs, 26 ° 51.164'S: 32 ° 12.365'E, subtropical bush, beats, short shrubs, 3.xii.2000 ( NMSA 21865 ) ; 1ơ Southern boundary fence, 26 ° 55.578'S: 32 ° 19.081'E, deep sand forest, beats, short shrubs, 11.i.2007 ( NCA 2007 /3041) ; 1ơ 26 ° 52.464'S: 32 ° 16.050'E, subtropical bush, A.nigrescens woodland, beats, foliage, 8.vii.2000 ( NCA 2008 /2742) .

Distribution: Species recorded in Kenya, Tanzania and South Africa.

Habitat and biology: This species was collected from foliage in BW, SF and ST. Two different colour morphs could be recognised: a black form that appears to mimic Streblognatha or Camponotus ants, and an orange variation that resembles Oecophila ants. The mimicry effect is enforced by the very elongate body with constrictions of the thorax and abdomen, and the gait and movements of the antennae.