Nesomyrmex tshiguvhoae, Mbanyana, N. & Robertson, H. G., 2008

Mbanyana, N. & Robertson, H. G., 2008, Review of the ant genus Nesomyrmex (Hymenoptera: Formicidae: Myrmicinae) in southern Africa., African Natural History 4, pp. 35-55 : 35

Nesomyrmex tshiguvhoae sp. nov.

Fig. 4a -c

Description of worker

Holotype. HL 0.885, HW 0.677, HW1 0.777, CI 76, SL 0.696, SI 103, PW 0.482, ML 1.052, EL 0.290, EI 43.

Mandibles predominantly smooth, with longitudinal striations in parts. Median clypeus smooth and bordered by two pairs of longitudinal striations beyond which are further shorter striations. Anterior clypeal margin convex in dorsal view with a projecting translucent lamella medially. Eyes large with 16 ommatidia in the longest row. Scapes relatively long (SI 103). Head in full with face-view hind margin evenly convex. Promesonotum in profile evenly convex. Metanotal groove deeply impressed with a few strongly developed cross ribs. Metapleural gland bulla massively developed, particularly noticeable in dorsal view. Propodeal dorsum long and shallowly convex and sloping down to a short declivity that is demarcated from the dorsum by a pair of angled projections, too short to be termed teeth. Metapleural lobes low and rounded. Anterior peduncle with a small, shallow keel-like subpetiolar process. Anterior and dorsal faces of the node form a well-defined angle, from which the short dorsal face slopes evenly into the posterior face. Postpetiole similar in height to petiolar node and more bulky and rounded. Headinfull face view smooth and shiny posteriorly and medially, with a few fine striations posterior tothe lobes. Promesonotal dorsum smooth and shining, with superficial reticulate sculpture towards the metanotal groove. Metanotal groove with cross-ribs. Propodeal dorsum and declivity with transverse rugulae becoming irregular anteriorly. Petiolar node and postpetiole with irregular, superficial reticulate sculpture. Base of first gastral tergite with short costulae and the rest of the tergite smooth and shining. Dorsum of head with 10 short suberect hairs and sparse pubescence present. The venter of head with five curved hairs. Six pairs of erect hairs on the promesonotum; three pairs of erect hairs on the propodeum; four suberect hairs on the petiolar node; and six suberect hairs on the postpetiole; sparse pubescence present. Gastral tergite and sternite with evenly distributed short suberect hairs, acute apically. Colour uniformly dark brown.

Paratypes. HL 0.767-0.924, HW 0.570-0.705, HW1 0.637-0.801, CI 73-78, SL 0.561-0.718, SI 94-105, PW 0.420-0.526, ML 0.865-1.114, EL 0.219-0.311, EI 38-44. (9 of 30 measured).

Same as holotype except the following differences: mandibles either with longitudinal striations or smooth and shining. The dorsum of head with up to 15 suberect hairs; the venter of head with 5-10 curved hairs. Base of first gastral tergite with or without short costulae.

Diagnosis

This is a distinctive dark brown species with metapleural gland bulla large and bulging so that in dorsal view the sides below the propodeum are convex along their medial length; whereas in other species metapleural gland bulla is not prominent, indorsal view the sides below the propodeum are more-or-less straight along their medial length.

Biology

Recorded from Nama-Karoo north of Prince Albert and Renosterveld on tillite in the Nieuwoudtville region. Most specimens were caught in pitfalls but they were also in yellow pan traps, Malaise traps and from sweeping of vegetation.

Etymology

Named after Thidinalei Ennie Tshiguvho, who collected the holotype.

Material examined

Holotype: South Africa: Western Cape: 26 km from Prince Albert on Leeu Gamka road , 32°59'S 22°00'E, 10-19 October 1996, T.E. Tshiguvho, SAM-HYM-C009355 .

Paratypes: South Africa: Western Cape: 26 km from Prince Albert on Leeu Gamka road , 32°59'S 22°00'E, 10-19 October 1996, T.E. Tshiguvho, SAM-HYM-C009360 & SAM-HYM-C009356 ; 15 km from Prince Albert on Leeu Gamka road , 32°05'S 22°02'E, 10-19 October 1996, T.E. Tshiguvho, SAM-HYM-C009362 , SAM-HYM-C009361 & SAM-HYM-C009359 ; Northern Cape: Hotbergsfontein farm, Boophone Site (4.64 km 125° SE Nieuwoudtville ), 31°23'18"S 19°9'36"E, 12-19 October 2000, H.G. Robertson, D. Larsen & R. Adams, NW00-DN3-P07 , SAM-HYM-C 019120 ; Hotbergsfontein farm, Boophone Site (4.64 km 125° SE Nieuwoudtville ), 31°23.296'S 19°09.608'E, 12-19 October, S. van Noort & H.G. Robertson, NW00-DN3-Y217 , SAM-HYM-C019121 .

Other material

South Africa: Western Cape: 42 km from Prince Albert on Leeu Gamka road , 32°58S 21°58E, 10-19 October 1996, T.E. Tshiguvho, Site 30 Trap 5, SAM-HYM-C009358 ; Bleakhouse farm, Site B3 , Nama-Karoo on dolerite soils, Pitfall, 32°15.41'S 22°54.93'E, 21-28 April 2001, H.G. Robertson & R. Tourle, BW01-B3-P10 , SAM-HYM-C 019108 ; Kamferskraal farm, Site K4 , Nama-Karoo on dolerite soils, Pitfall, 32°16.92'S 23°01.13'E, 22-29 April 2001, H.G. Robertson & R. Tourle, BW01-K4-P07 ; SAM-HYM-C019109 ; Kamferskraal farm, Site K4 , Nama-Karoo on dolerite soils, Pitfall, 32°16.92'S 23°01.13'E, 22-29 April 2001, H.G. Robertson & R. Tourle, BW01-K4-P10 ; SAM-HYM-C019110 ; Kamferskraal farm, Site K5 , Nama-Karoo on dolerite soils, Malaise trap, 32°17.45'S 23°58.46'E, 23 April 2001, S. van Noort & H.G. Robertson, BW01-K5- M16 ; SAM-HYM-C019111 ; Avondale farm, Site A3 , Nama-Karoo on dolerite soils, Sweep, 32°13.33'S 22°57.53'E, Nama-Karoo on dolerite soils, Sweep, 19 April 2001, S. van Noort, BW01-A3-S104 , SAM-HYM-C019112 ; Elandsfontein farm, Site E4 , 32°17'41"S 23°0'0"E, 18 April 2001, H.G. Robertson, HGR00191 , SAM-HYM-C017657 ; Helderberg Nature Reserve, Somerset West , 34°2'26"S 18°52'40"E, 01 March 2006, B. Braschler, Iimbovane 010306 1.9, SAM-HYM-C 019791 ; Beaufort West Karoo N.P. , 32°20'23"S 22°31'19"E, flat Nama-Karoo, 12 March 2006, B. Braschler, Iimbovane Kar120306 F1.1 , SAM-HYM-C019796 ; Beaufort West Municipal Land, near Central High School , 32°21'20"S 22°35'43"E, flat heavily disturbed Nama-Karoo, 13 March 2006, B. Braschler, Iimbovane SEN130306 2.3 , SAM-HYM-C 019797 ; Northern Cape: Kortkop farm near Strydenburg , 30°09'S 23°44'E, Karoo vegetation, ex pitfall trap, 17 June 1995, B. Chambers, SAM-HYM-C008784 ; Merriman Station between Richmond and Britstown, 31°11'S 23°34'E, collected in the Karoo, March 2007, F. Duncan, PP1#2, SAM-HYM-C019581 .