Paratrechina umbella (LaPolla & Fisher)

Type location Cameroun (Nylanderia umbella n. sp., LaPolla & Fisher, 2011: 24, illustrated, worker) collected at Mbalmayo, by N Stork, xi.1993; worker only described .

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

Description. 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 hairs [macrosetae] and a dense layer of pubescence (SMC = 13–16). Alitrunk with erect hairs of varying lengths concentrated on posterior pronotum and mesonotum (PMC = 3–5; MMC = 2); layer of pubescence covers alitrunk 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 hairs and a dense layer of pubescence.

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

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°15′ N, 31°48′ 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, P. umbella appears closely related to P. boltoni and P. scintilla.

The photomontage of the holotype worker is collated from http://www.antweb.org/specimen.do?name=casent0179583

Oxford University Museum specimens

Paratrechina umbella B Taylor det.	Congo Y Braet t-1-2	19.viii.2007 Brazzaville 4° 15' 33" S 15° 17' 5" E	24h pitfall trap; forest around the GERDIB laboratories; 317 m asl	3
Paratrechina umbella B Taylor det.	Congo E Zassi 12-t-1	4-5.ii.2008 Lésio-Louna 03°20'12.0" S 015°28'43.6" E	Village Mah; 24h pitfall trap	2
Paratrechina umbella B Taylor det.	Congo Y Braet t-1-11	19.viii.2007 Brazzaville 4° 15' 33" S 15° 17' 5" E	24h pitfall trap; in a domestic garden near the GERDIB laboratories; 317 m asl	1
Paratrechina umbella B Taylor det.	Congo Y Braet t-1-19	19.viii.2007 Brazzaville 4° 15' 33" S 15° 17' 5" E	24h pitfall trap; forest around the GERDIB laboratories; 317 m asl	1
Paratrechina umbella B Taylor det. Male	Congo Y Braet t-1-20	19.viii.2007 Brazzaville 4° 15' 33" S 15° 17' 5" E	24h pitfall trap; in open ground around the GERDIB laboratories; 317 m asl	1
Paratrechina umbella B Taylor det.	Sudan Awatif Omer 2013.02.18	2013 Sinja 13˚09' N 33˚55'60" E		2
Paratrechina umbella B Taylor det.	Sudan Awatif Omer 2013.02.30	2013 Abu Hijar 12˚52' N 34˚0' E		2

The photomontage is of a worker from Congo, Brazzaville; collector Y Braet & E Zassi (t-1-2).  Apart from the slight flattening (possibly crushing of the alitrunk dorsum, this is an exact match for the LaPolla and Fisher worker shown above.

The photomontage is of a worker from Sudan, Abu Hijar; collector Awatif Omer.

The photomontage is of a worker from Congo, Brazzaville; pitfall trapped by Yves Braet & Eric Zassi (t 1.11).

The photomontage is of a worker from Congo, Brazzaville, pitfall trapped; collectors Yves Braet & Eric Nzassi (t-1-19)

The photomontage is of the possible male from Congo, Brazzaville, pitfall trapped, trap t 1.20, by Yves Braet & Eric Zassi, 19.viii.2007.