Nylanderia natalenis ( Forel, 1915 ) Forel, 1915

Lapolla, John S., Hawkes, Peter G. & Fisher, Brian L., 2011, Monograph of Nylanderia (Hymenoptera: Formicidae) of the World, Part I: Nylanderia in the Afrotropics, Zootaxa 3110, pp. 10-36 : 21-22

Nylanderia natalenis ( Forel, 1915) , stat. nov.

( Figs. 40–42 , 82 [worker]; 43–45, 95–97 [male])

Prenolepis (Nylanderia) traegaordhi natalensis Forel, 1915: 348 (worker described). 5 syntype workers, SOUTH AFRICA: Durban (MHNG) [examined]. Emery, 1925: 218, combination in Paratrechina (Nylanderia) ; LaPolla et al., 2010: 127, combination in Nylanderia .

Worker diagnosis: Overall brown, with abundant pubescence on head, anterior portions of pronotum, mesonotum and gaster.

Compare with: N. jaegerskioeldi

WORKER. Measurements (n = 5): TL: 2.3–2.7; HW: 0.53–0.64; HL: 0.66–0.71; EL: 0.14–0.2; SL: 0.7–0.76; PW: 0.39–0.47; WL: 0.73–0.86; GL: 0.9–1.2

Indices: CI: 81–93; REL: 21–28; SI: 119–132

Workers of this species cannot be reliably separated from N. jaegerskioeldi . N. natalensis worker description matches N. jaegerskioeldi worker description.

The queen caste is currently unknown for this species.

MALE. Measurements (n = 2): TL: 2.3–2.5; HW: 0.49–0.51; HL: 0.57–0.58; EL: 0.21–0.24; SL: 0.67–0.69; PW: 0.56–0.57; WL: 0.8–0.87; GL: 0.95–1.03

Indices: CI: 85–87; REL: 37–42; SI: 133–141

Overall brown, with mesosoma in some specimens lighter brown; trochanters, joints of legs, and tarsi yellowish-brown; cuticle smooth and shining, covered with dense pubescence, but mesopleuron and propodeum with sparser pubescence. Head with suberect to erect macrosetae, with a dense layer of pubescence; compound eyes large (taking up about half of the length of the lateral margin), but not strongly convex; ocelli relatively small. Scapes surpass posterior margin by about length of the first three funicular segments; scapes with scattered erect macrosetae (SMC = 17–25) and a dense layer of pubescence. Mandible with prominent apical tooth, 1–2 subapical teeth and distinct basal tooth. Mesosoma with dense pubescence, except for less dense pubescence on mesopleuron and propodeum; scattered erect macrosetae (PMC = 0; MMC = 9–10) dorsally. Dorsal face of propodeum slightly below level of mesonotum; dorsal face slightly sloped with declivitous face of about the same length; declivitous face smooth and shining with no pubescence. Gaster with suberect and erect macrosetae of varying heights. Genitalia (figs. 95–97): parameres broadly rounded at apices curving dorsally covering most of the dorsal opening; apical margin of parameres complete; ventral margin of parameres at an acute angle; cuspi elongated, apices rounded with peg-like teeth on ental surface where they meet digit; digiti apices broad; peg-like teeth at apices dorsally, ventrally coming to a narrow point that curves towards parameres.

Non-type material examined. LESOTHO: Mamathes, 30°0.993' S, 28°21.574' E *, 1702 m, Oct 1957; MOZAMBIQUE: Amatongas, 19°11.000' S, 33°45.000' E *, Feb 1917 (G. Arnold); SOUTH AFRICA: KwaZulu- Natal, Umtamvuna Nature Reserve, 31°30.509' S, 30°10.484' E, 160 m, 14 Nov 2000 (S. van Noort); KwaZulu- Natal, Umtamvuna Nature Reserve, 31°02.704' S, 30°10.080' E, 220 m, 18 Nov 2000 (S. van Noort); Durban, 29°51.473' S, 31°1.655' E *, Jan 31 1917 (G. Arnold); Illovo, 29°50.000' S, 30°12.000' E *, 11 May 1976 (A.J.M. Carnegie); Nelspruit, Transvaal, 25°27.950' S, 30°59.117' E, June 1980 (M. Samways); Natal, Ifafa,, 29°52.000' S, 31°3.000' E, 16 June 1979 (G. Leslie); Willowmore, 33°17.996' S, 23°28.883' E *, Jan 1914 (H. Brauns); ZIMBA- BWE: Umtali, 18°58.486' S, 32°39.334' E *, 10 June 1920 (G. Arnold).

Notes. Workers of N. natalensis and N. jaegerskioeldi are impossible to reliably tell apart from each other. It appears that N. natalensis is slightly less pubescent than N. jaegerskioeldi , but this is hard to qualify, and we have not always found it a reliable diagnostic feature. An interesting point, however, is that the male genitalia of these two species are very different, especially the size and shape of volsella and the associated lobes. Males of each are easily distinguishable. The digiti and cuspi of N. natalensis (fig. 97) are similar in structure to N. boltoni , N. lepida , and N. silvula (figs. 91, 94, 103). In these species, the cuspi are lobe-like and not nearly as wide as the digiti, and in general fairly typical in appearance for what is observed in Nylanderia species in other parts of the world. In N. jaegerskioeldi the cuspi are much larger than the digiti and paddle-like (fig. 100); additionally the digiti are thin and blade-like, an unusual shape for Nylanderia digiti. There are differences in the paramere shape as well between N. natalensis and N. jaegerskioeldi . In N. natalensis the paramere margin is broadly rounded (fig. 96), whereas N. jaegerskioeldi has a finger-like extension of the margin (fig. 99). In general, it would appear that N. natalensis is restricted to southern Africa, while N. jaegerskioeldi has a wider range from across equatorial Africa to northern Africa.

Figures

FIGURES 31 – 45. Afrotropical Nylanderia species in various views: lepida (male, 31 – 33, CASENT 0217337, Gabon); luteafra (worker, 34 – 36, CASENT 0179584, Gabon); mendica (worker, 37 – 39, CASENT 0179590, Gabon); natalensis (worker, 40 – 42, CASENT 0396096; male, 43 – 45, CASENT 0396027; both from South Africa)

FIGURES 73 – 88. Scapes of Afrotropical Nylanderia species (workers only): boltoni (73, CASENT 0179580, Gabon); bourbonica (74, CASENT 0101309, Reunion); brevisetula (75, CASENT 0090304, Central African Republic); impolita (76, CASENT 0179589, Gabon); incallida (77, CASENT 0179576, Ivory Coast); jaegerskioeldi (78, CASENT 0179577, Kenya); lepida (79, CASENT 0179591, Gabon); luteafra (80, CASENT 0179584, Gabon); mendica (81, CASENT 0179590, Gabon); natalensis (82, CASENT 0396096, South Africa); scintilla (83, CASENT 0179579, Ivory Coast); silvula (84, LACMENT 272717, Kenya); umbella (85, CASENT 0179583, Cameroon); usambarica (86, CASENT 0235343, Tanzania); vaga (87, CASENT 0104253, U. S. A); vividula (88, CASENT 0103260, U. S. A.)