Key to the Sri Lankan species of Myrmarachne

1. Tegulum of the male palp cylindrical, embolus is positioned on distal end of the tegulum, spermatheca kidney-shaped, connected by a CD to CO. Proximal half of chelicerae constricted. Generally not found in primary forest (Figures 30A–D, 31A, 35B, 36C, 37B, D) .................................................................... 2

– Tegulum spherical or disk-shaped, embolus is positioned on outer edges of the tegulum, spermatheca elongated tubes or oval. Generally found in primary forest (Figures 3A, F, 4B, 22A) ...................................................................... 3

2(1). Spiders brown in colour, large (7.2–30.0), Figure 29A, B ........ M. plataleoides

– Spiders black in colour, much smaller (6.4–3.6), Figure 33A–D ........ M. spissa

3(1). Spermatheca oval, connected by a CD to CO ................................................ 4

– Spermatheca an elongated tube, no clear distinction of CD ........................... 5

4(3). Adult spiders brownish with thoracic part black .................. M. melanocephala

– Adult spiders black with thoracic part red/brown (Figures 23A–E, 24A–D) ............................................................................................................. M. prava

5(3). Opisthosoma cylindrical, as much as 3× longer than wide, no constriction (Figures 5A–C, 8G, H, 9A–D) ....................................................................... 6

– Opisthosoma oval or round, less than 2× longer than wide, constriction present in the centre of the anterior half of opisthosoma ........................................... 7

6(5). Adult spiders brownish with conspicuous white bands on prosoma and chelicerae (Figures 5A–C, 8G, H) ..................................... M. dishani sp. n.

– Adult spiders dark brown with no white bands on prosoma or chelicerae (Figure 9A–D) .............................................................................. M. imbellis

7(5). male palp longitudinally oval, embolus is positioned away from the borders of the tegulum (Figure 3A, F) .................................................................... 8

– Male palp circular, disk-shaped, embolus is positioned on the borders of the tegulum, small spiders (Figures 7B, 22A) ................................................... 9

8(7). Chelicerae with parallel lateral sides, distal half slightly wider than the proximal half, RTA hook-shaped with a constriction at the base (Figures 2A, B, 3B, 4D, E) ...................................................................................... M. bicurvata

– Distal half of the chelicerae wider than the proximal half, The inner and outer sides of the proximal half are parallel, whereas the distal half has convex outer sides and parallel inner sides, RTA of the male palp is broad based and tapered to a point in one corner (Figures 2E, F, 3E, F) ............. M. ramunni

9(7). Chelicerae fangs with a bulbous base, thickest at the centre (Figure 38A, B) ................................................................................................... M. aff. tristis

– Chelicerae without a bulbous base, if base constricted, the entire proximal half is constricted ...................................................................................... 10

10(9). Chelicerae outer sides more or less parallel, dorsum curved, body covered with fine white hairs (Figures 14A–G, 15A, B) ........ M. paludosa comb. nov.

– Entire proximal or distal half of chelicerae constricted or dorsal surface flat (Figure 21A, B) ......................................................................................... 11

11(10). Proximal half of chelicerae constricted, distal half laterally rounded, dorsal and ventral surfaces well rounded forming a bulb (Figure 21A, B) ............... .................................................................................. M. morningside sp. nov.

– Chelicerae proximal half not constricted, dorsal surface flat (Figure 1A, B). .................................................................................... M. aurantiaca sp. nov.

Taxonomy

Family Salticidae

Genus Myrmarachne MacLeay, 1839

Panachraesta Simon, 1900: 405 . Type species by original designation P. paludosa Simon, 1900: 405, examined. New synonymy.

Remarks

The type species of Myrmarachne, M. melanocephala was redescribed and a neotype designated by Edwards and Benjamin (2009). The type species of Panachraesta is here considered a typical member of the genus Myrmarachne; see redescription of the species below. Diagnosis and description for the genus is provided by Wanless (1978),

Edwards and Benjamin (2009), Prószyński and Deeleman-Reinchold (2010) and Yamasaki and Ahmad (2013).