Myrmarachne spissa ( Peckham and Peckham, 1892 ), 1901

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 : 2652-2656

Myrmarachne spissa ( Peckham and Peckham, 1892)

( Figures 32A–J , 33A–D , 34A–D , 35A–F , 36A–C , 37A–F )

Salticus spissus Peckham and Peckham, 1892: 37 .

Myrmarachne spissa ( Peckham and Peckham, 1892) Simon, 1901: 500 .

Type material

Syntypes ( MCZ 23159): 4 males from Ceylon (now Sri Lanka), leg. Green, GW and EG Peckham collection . Syntypes variable in size. The medium sized specimen was selected for drawing.

Diagnosis

Separated from all other Sri Lankan species of the genus, except for M. plataleoides by the cylindrical tegulum of the male palp, with an embolus positioned on the distal end of it and the kidney-shaped S connected by an elongated CD to CO ( Figures 35A–F , 36A–C , 37A–F ). Separated from M. plataleoides by the smaller size and uniformly black colour ( Figures 33 , 34 ). Further, this species could be separated from M. morningside sp. nov. by the presence of white setae mostly of the dorsal parts of the prosoma and the presence of two whitish, elongated setae approximately on the centre of the prosoma ( Figures 33 , 34 ).

Description

Male: total length: 6.4–4.2; prosoma length: 4.0–2.5, width: 1.4–0.9. Leg I: femur 1.2, patella 0.5, tibia 1.2, metatarsus 0.7, tarsus 0.4. Prosoma elongated, almost as 2 times longer than wide. Opisthosoma oval, a bit longer than wide. Live spiders fully black in colour ( Figures 33 , 34 ). Spiders of this species have a whitish appearance, mostly of the dorsal parts of the prosoma due to the presence of short white setae ( Figures 33 , 34 ). Two white, elongated setae approximately on the centre of the prosoma are present ( Figures 33 , 34 ). Alcohol preserved specimens are dark to light reddish-brown in colour. Prosoma raised, red/brown to red/yellow, chelicerae large relative to body size, almost as long as prosoma, opisthosoma with 2 sclerotized scutae ( Figure 32A – J ). Chelicerae dentition not examined. Leg formula 4132. Leg spination not examined. Male palps with a cylindrical tegulum, with an embolus positioned on the distal end of it as in Figure 35A – F . Female from Inginiagala: total length: 3.6; prosoma length: 1.6, width: 0.9. Leg 1: femur 0.8, patella 0.3, tibia 0.6, metatarsus 0.4 tarsus 0.2. Morphology as above, except for the lighter coloured prosoma and opisthosoma ( Figure 32A – J ). Some females seem to have reddish-brown chelicerae ( Figure 34 ). Chelicerae dentition not examined. Leg formula 4132. Leg spination not examined. Epigynum and vulva as in Figure 36A–C .

Distribution

Sri Lanka.

Variation

The Monaragala District specimen is a bit larger than the specimen from Padaviya. Some recently collected specimens are darker, the light colour of the types might be due to preservation.

Natural history

Specimens from Atidiya live in association with a species of ants of the genus Technomyremex (vouchers deposited in MHNG). Specimens from Kurunagala, Nikaravatiya were collected with ants of the genus Cataulacus .

Other material examined

Sri Lanka, Uva Province, 1 male, Monaragala District, Angunakolaplesse 100 m, 21–23 January 1979, K.V. Krombein, P.B. Karunaratne, T. Wijesinhe, S. Siriwardane, T. Gunawardane, USNM . 1 male 1 female, Monaragala District (probably Ampara District), Inginiagala , 3 June 1995, D.H. Messersmith, G.L. Williams and P.B. Karunaratne, USNM . North Central Province, 1 male. Anuradapura District, Padaviya , 19 May 1976. Leg K.V. KROMBEIN(?), USNM . Eastern Province, 1 male, Ampara District, Inginiyagala, Gal Oya NP , c. 80 m, 07°13 ʹ 22 ″ N, 81°31 ʹ 56 ″ E, 10 February 2010, leg. S.P. Benjamin, S. Batuwita, MHNG . Western Province, 1 male 1 female, Colombo District, Bellanwila-Attidiya, 21 February 2000, S.P. Benjamin. 5 males, Panadura , Mahabellana , along Bolgoda South Lake , July 2008, S.P. Benjamin, S.K. Dayananda and Z. Jaleel, MHNG . North Western Province, 11 males, 5 females, Kurunagala District, Kurunagala, Ethagala Mountains , c. 300 m, 1–28 February 2007, Z. Jaleel, MHNG . 2 males, 11 October 2008, Z. Jaleel, MHNG . 6 males, 1–30 March 2008, leg. Z. Jaleel, MHNG . 2 females, Ethagala range , c. 190 m, 07° 28 ʹ 17 ″ N, 80°22 ʹ 30 ″ E, 24 November 2009, Hand collecting, leg. S.P. Benjamin, S. Batuwita, Z. Jaleel, MHNG . Central Province, 1 male, 2 females, Kandy District, Dunumadalawa , c. 600 m, 07°17 ʹ 00 ″ N, 80°37 ʹ 49 ″ E, 24 September 2009, leg. S.P. Benjamin et al., MHNG . 1 male, 1 female, Matale District, IFS Arboretum , c. 180 m, 07°51 ʹ 34 ″ N, 80°40 ʹ 28 ″ E, 24 August 2010, Hand collecting, leg. S.P. Benjamin, S. Batuwita. 1 male ‘no label’ USNM Sri Lanka collection ( Sri Lanka?), MHNG .

Figures

Figure 32. Photographs of Myrmarachne spissa. (A–C) male syntype (MVZ 23159); (D) male from Angunakolaplesse; (E,F) male from Padaviya; (G,H) male from Bellanwila-Attidiya; (I,J) female from Bellanwila-Attidiya. (A,D,E,G,I) lateral view; (B,C,F,H,J) dorsal view.

Figure 33. Myrmarachne spissa, male in life.

Figure 34. Myrmarachne spissa, female in life.

Figure 35. Myrmarachne spissa. (A–F) male palp. (A,B) male from Bellanwila-Attidiya; (C,D) male from Angunakolaplesse; (E,F) syntype, right palp (MVZ 23159). (A,C,E) retrolateral view; (B,D,F) ventral view. Scale bars = 0.2 mm.

Figure 36. Myrmarachne spissa. (A–C) female from Bellanwila-Attidiya. (A) epigynum, ventral view; (B) vulva, dorsal view; (C) vulva, ventral view. Scale bars = 0.1 mm.

Figure 37. Scanning electron micrographs of Myrmarachne spissa from Padaviya. (A–F) right male palp. (A) prolateral view; (B,D–F) ventral view; (C) retrolateral view. Scale bars = 10 µm (F); 20 µm (A–E).