Nylanderia usambarica LaPolla, Hawkes 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 : 24-25

Nylanderia usambarica LaPolla, Hawkes and Fisher , sp. nov.

( Figs. 61–63 , 86 )

Holotype worker, TANZANIA: Tanga Region, Nilo Forest Reserve, 1006 m, 4.91456 S, 38.67712 E, 1–4.ix.2005, CEPF-4.4-F24, (P. Hawkes, J. Makwati, R. Mtana) ( SAMC) (SAM-HYM-C 020684); 11 paratype workers, 9 same label data as holotype, 1 same data but CEPF-4.2-F35, 1 same data but CEPF-4.4-F33 ( USNM, CASC, NMKE, SAMC)

Worker diagnosis: Abundant macrosetae of varying lengths on pronotum (PSC = 10–22); macrosetae on head, mesosoma and legs dark and contrasting strongly with the much lighter cuticle; propodeal dorsum not domed.

Compare with: N. luteafra , N. natalensis and N. jaegerskioeldi

WORKER. Measurements (n = 6): TL: 2.3–2.8; HW: 0.55–0.64; HL: 0.67–0.74; EL: 0.14–0.16; SL: 0.73– 0.80; PW: 0.41–0.47; WL: 0.77–0.90; GL: 0.90–1.4

Indices: CI: 82–87; REL: 20–22; SI: 123–133

Overall golden yellow-brown, with lighter golden yellow antennae and legs; head and gaster slightly darker than mesosoma; legs nearly uniform in color, with coxae and trochanters slightly lighter than the remaining segments; cuticle smooth and shining but with faint, almost effaced shagreening, which is more noticeable on lateral propodeum and gaster; macrosetae on head, mesosoma and legs dark and contrasting strongly with the much lighter cuticle; macrosetae on scapes lighter. Head dorsally with abundant macrosetae and a layer of fine pubesence which becomes sparse anterolaterally; posterior margin distinctly emarginate medially; posterolateral corners strongly rounded and sides convex, giving the head a distinctly rounded appearance in full face view; scapes surpass posterior margin of head by about the length of the first 3–4 funicular segments; scapes with scattered erect macrosetae and a dense layer of pubescence (SMC = 24–32). Mesosoma with erect macrosetae of varying lengths on pronotum and mesonotum (PMC = 10–22; MMC = 3–4); pubescence sparse and scattered on pronotum and mesonotum; metanotal area compact; dorsal face of propodeum short and low (lower than mesonotum), rounding broadly into the longer declivitous face; propodeal dorsum and sides with pubescence; declivity smooth and shining with no pubescence. Gaster with erect macrosetae and a layer of sparse pubescence.

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

Etymology. The specific epithet usambarica refers to the East Usambara mountain range in which the type series was collected.

Notes. This species is currently known only from its type locality in Tanzania. It is most likely to be confused with callows of N. natalensis and N. jaegerskioeldi but it can be separated from these by the higher PMC and the distinctly indented posterior margin of the head. While the color of N. usambarica is similar to that of N. luteafra , these species can be readily distinguished by the strongly domed propodeal profile of the latter. N. usambarica has the highest PMC of any Afrotropical Nylanderia species currently known.

Figures

FIGURES 61 – 72. Afrotropical Nylanderia species in various views: usambarica (worker, 61 – 63, CASENT 0235343, Tanzania); vaga (worker, 64 – 66, CASENT 0104253, U. S. A.); vividula (worker, 67 – 69, CASENT 0103260, U. S. A.); waelbroecki (male, 70 – 72, USNMENT 00693679, D. R. Congo)

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.)