Myrmarachne ramunni Narayan, 1915

Benjamin, Suresh P., 2015, Model mimics: antlike jumping spiders of the genus Myrmarachne from Sri Lanka, Journal of Natural History 49 (43), pp. 2609-2666 : 2651

Myrmarachne ramunni Narayan, 1915

( Figures 2E, F , 3E, F )

Myrmarachne ramunni Narayan, 1915: 400–402 , figure 4a–c.

Identification

Types have not been examined. Narayan (1915) illustrates and describes the unique chelicerae of this species, aiding positive identification.

Material examined

Sri Lanka, Eastern Province, 1 male, Ampara District, Inginiagala, 250 ff, Samudra gardens, 22–23 November 1976, G.F. Havel, R.E. Dietz IV, S. Karunaratne, USNM .

Diagnosis

Very similar to M. bicurvata , however, males are easily separated by the chelicerae. The distal half of the chelicerae of M. ramunni is wider than the proximal half ( Figure 2E ). The inner and outer sides of the proximal half are parallel, whereas the distal half has convex outer sides and parallel inner sides. M. bicurvata has parallel inner and outer sides ( Figure 2A, C ). The RTA of the male palp is broad base and tapered to a point in one corner. In M. bicurvata the RTA is hook-shaped with a constriction at the base ( Figure 3B, E ).

Description

Male: total length: 6.8; prosoma length: 4.4, width: 1.2. Leg I: femur 1.6, patella 0.6, tibia 1.6, metatarsus 0.8, tarsus 0.4. The cephalic part of the prosoma is elevated and rounded on all sides. The thoracic part is lower than the cephalic, the highest point being the centre ( Figure 2E, F ). Opisthosoma oval, almost as wide as long, with no clear constriction ( Figure 2E, F ). Dorsally sclerotized, ventrally softer. Chelicerae are characteristically long and stout, distal half is wider than the proximal half ( Figure 2E, F ). The distal half is hammer-shaped. The inner and outer sides of the proximal half are parallel, whereas the distal half has convex outer sides and parallel inner sides. Chelicerae dentition not examined. Leg formula 4132. Leg spination not examined. Palps as in Figure 3E, F . Female: remains unknown, but see Dyal (1935) for a description of a female attributed to this species.

Natural history

Borges et al. (2007) associated the ant Myrmicaria brunnea with this species (spiders identified as Myrmarachne morphospecies 3).

Distribution

India, Pakistan, Sri Lanka.

Figures

Figure 2. (A–D) Myrmarachne bicurvata. (A,B) male from Lahugala; (C,D) holotype, Sri Lanka, OUMNH. (E,F) Myrmarachne ramunni from Inginiyagala. (A,C,F) dorsal view; (B,D,E) retrolateral view.

Figure 3. (A–D) Myrmarachne bicurvata. (A,B) male from Lahugala; (C,D) holotype, Sri Lanka (OUMNH); (E,F) Myrmarachne ramunni from Inginiyagala; (A,C,F) ventral view; (B,D,E) retrolateral view. Scale bars = 0.2 mm.