Nylanderia umbella LaPolla and Fisher

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 : 24

Nylanderia umbella LaPolla and Fisher , sp. nov.

( Figs. 58–60 , 85 [worker])

Holotype worker, CAMEROON: Mbalmayo, xi.1993 (N. Stork) ( BMNH); 3 paratype workers, same label data as holotype ( BMNH)

Worker diagnosis: Head width less than 0.51 mm; head, mesosoma, and gaster dark brown, contrasting sharply with yellowish-brown antennae, mandibles, mesocoxae, metacoxae, and legs; very short, angular, propodeal dorsal face.

Compare with: N. boltoni and N. scintilla

WORKER. Measurements (n = 3): TL: 2.1–2.4; HW: 0.49–0.51; HL: 0.59–0.61; EL: 0.14–0.16; SL: 0.62– 0.64; PW: 0.35–0.38; WL: 0.62–0.69; GL: 0.92–1.2

Indices: CI: 80–84; REL: 23–27; SI: 123–130

Overall dark brown, with lighter brown to yellow mandibles, antennae, and legs; cuticle smooth and shining; procoxae dark brown, with mesocoxae and metacoxae yellow-brown to yellow in color. Head with a dense layer of pubescence; posterior margin with rounded posterolateral corners, slightly emarginate medially; scapes surpass posterior margin by about the length of the first two funicular segments; scapes with scattered erect macrosetae and a dense layer of pubescence (SMC = 13–16). Mesosoma with erect macrosetae of varying lengths concentrated on posterior pronotum and mesonotum (PMC = 3–5; MMC = 2); layer of pubescence covers mesosomal notum; metanotal area compact; dorsal face of propodeum angular and low (lower than mesonotum) with very short dorsal face and longer declivitous face; propodeum dorsum with pubescence; declivity smooth and shining with no pubescence. Gaster with abundant erect macrosetae and a dense layer of pubescence.

The queen and male castes are currently unknown for this species.

Etymology. The species epithet umbella (L. = shade or shadow) is in reference to the dark brown coloration of this species.

Non-type material. UGANDA: Murchison Falls National Park, Rabongo Forest, 02°15ʹ N, 31°48ʹ E*, 958 m, 11 July 2009 (W. Freund & T. Klug)

Notes. This is among the darkest of the Afrotropical species, with strongly contrasting antennae, coxae, and legs. Based on overall similarities in size and shape, N. umbella appears closely related to N. boltoni and N. scintilla .

Figures

FIGURES 46 – 60. Afrotropical Nylanderia species in various views: scintilla (worker, 46 – 48, CASENT 0179579, Ivory Coast); silvula (worker, 49 – 51, LACMENT 272717; queen 52 – 54, LACMENT 272721; male, 55 – 57, LACMENT 272719; all from Kenya); umbella (worker, 58 – 60, CASENT 0179583, Cameroon)

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.)