Corresponding author: John S. LaPolla (
Academic editor: Wojciech Pulawski
With the recent finding of
Recently the ant genus
One particularly interesting and important aspect of
The unusual morphology of
Specimens examined for this study are deposited in the following institutions:
AfriBugs, Pretoria, South Africa
Australian National Insect Collection, Canberra, Australia
California Academy of Sciences, San Francisco, CA, USA
Museum of Comparative Zoology, Cambridge, MA, USA
National Museum of Kenya, Nairobi, Kenya
Iziko South African Museum, Cape Town, South Africa
National Museum of Natural History, Washington, DC, USA
Measurements were taken using an eyepiece graticule with a Leica MZ16 microscope mounted on an axial shift carrier to avoid parallax errors, recorded to the nearest 1/10 graticule unit and lengths calculated using calibration data from a stage micrometer for each magnification. All measurements are given in millimeters. Digital color images of a
(Eye Length): maximum length of compound eye in full-face view
(Gaster Length): the length of the gaster in lateral view from the anteriormost point of the first gastral segment (third abdominal segment) to the posteriormost point
(Head Length): the length of the head proper, excluding the mandibles; measured in full-face view from the midpoint of the anterior clypeal margin (a line is drawn between the projecting lateral portions of the clypeus to accommodate the anterior margin which is medially indented in
(Head Width): the maximum width of the head in full-face view, excluding eyes
(Mesonotal Setal Count): the number of erect macrosetae on mesonotum to one side of the sagittal plane
(Pronotal Width): the maximum width of the pronotum in dorsal view
(Profemur Length): the length of the profemur from its margin with the trochanter to its margin with the tibia
(Pronotal Setal Count): the number of erect macrosetae on pronotum to one side of the sagittal plane
(Scape Setal Count): the number of erect macrosetae on one antennal scape, excluding the terminal setal cluster
(Scape Length): the maximum length of the antennal scape excluding the condylar bulb
(Total Length): HL+WL+GL
(Weber’s Length): in lateral view, the distance from the posteriormost border of the metapleural lobe to the anteriormost border of the pronotum, excluding the neck
(Cephalic Index): (HW/HL) • 100
(sensu
(Scape Index): (SL/HW) • 100
Since the new species described here is only known from the worker, we provide only a worker-based definition for the genus pending the discovery of males and queens for
Monomorphic, medium sized (2.1–3.2 mm in total length) formicine ants; brown to dark brown in color, with lighter mandibles, antennae (especially funicular segments towards tips) and legs (especially distal portion of tibiae and tarsi). Head with medially erect macrosetae roughly paired, extending through the medial portion of clypeus. Cuticle on the head smooth and shining, with faint shagreenate sculpture, especially towards the posterior margin. Antennae 12 segmented; scapes very long, with scape index above 180, usually above 200 (SI 183–220). Scapes with a dense layer of pubescence. Head is distinctly longer than wide, with cephalic index below 100 (CI 71-94); posterolateral corners rounded, with straight posterior margin. Eyes large relative to head width (REL2 greater than 35); eyes distinctly convex, extending beyond head margin in full frontal view; three small but distinct ocelli present. Mandibles typical for
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For a genus-level key see
1 | Scapes without erect macrosetae ( |
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– | Scapes with erect macrosetae ( |
Scapes without erect macrosetae.
WORKER. Measurements in millimeters (n=4): TL: 2.1-2.5; HW: 0.46-56; HL: 0.49-0.7; EL: 0.17-0.23; SL: 0.98-1.16; PW: 0.34-0.43; WL: 0.82-0.98; PrFL: 0.6-0.9; GL: 0.83-0.9.
Indices: CI: 73-94; REL2: 38-42; SI: 182-226.
Overall coloration pale to very dark brown, often with a distinct blueish iridescent sheen, especially on the mesosoma and gaster. Mandibles, antennae and legs (especially the trochanters of all legs, which are a strongly contrasting very pale yellow-brown) much lighter in color; cuticle smooth and moderately shining with faint shagreenate sculpture, which is most obvious on head and gaster. Head narrow, distinctly longer than broad, with abundant pale (yellow-brown to almost white), erect macrosetae; anterior clypeal margin with a shallow medial indentation; scapes with a dense layer of very fine pubescence but lacking erect macrosetae; eyes large and convex, extending beyond head lateral margin in full frontal view; posterior head margin with rounded posterolateral corners; three distinct ocelli present. Mesosoma with scattered pale erect macrosetae (PSC = 3; MSC = 3-4); in profile pronotum and mesonotum almost flat dorsally, with a broadly angled junction; metanotal area relatively indistinct, medially about 1/5 the length of the mesonotum but longer laterally than medially; dorsum of propodeum almost flat to very shallowly domed, rounding evenly into the short declivitious face; anterolateral portion of dorsal face with some scattered pubescence. Gaster with abundant erect pale macrosetae.
The authors have examined hundreds of specimens of
Scapes with abundant erect macrosetae.
WORKER. Measurements in millimeters (n=18): TL: 2.6-3.2; HW: 0.50-0.59; HL: 0.68-0.77; EL: 0.19-0.23; SL: 1.07-1.24; PW: 0.41-0.5; WL: 0.94-1.20; PrFL: 0.78-0.91; GL: 0.92-1.30.
Indices: CI: 71-79; REL2: 37-44; SI: 198-220.
Overall coloration dark brown with lighter mandibles, antennae (especially funicular segments towards tips) and legs (especially trochanters of mid and hind legs, and distal portions of tibiae and tarsi); cuticle smooth, shining, and with very faint shagreenate sculpture, which is more obvious on head and gaster. Head narrow, distinctly longer than broad, with abundant dark, erect macrosetae; anterior clypeal margin with a shallow medial indentation; scapes with a dense layer of pubescence and scattered erect macrosetae (SSC = 17-29); eyes large and convex, extending beyond head lateral margin in full frontal view; posterior head margin with rounded posterolateral corners; three distinct ocelli present. Mesosoma with scattered dark erect macrosetae (PSC = 2-5; MSC = 2-3); in profile pronotum and mesonotum shallowly convex dorsally, presenting a uniform overall curvature through their junction; metanotal area distinct, about 1/3 the length of the mesonotum; dorsal face of propodeum rounded, with short declivitious face; anterior portion of dorsal face with thin layer of pubescence. Gaster with abundant erect dark macrosetae.
The specific epithet is derived from the ancient Arabic name for the stretch of East African coast that encompasses parts of modern day Kenya, Mozambique, and Tanzania.
Very little is known about the natural history of
The worker of
Scape length versus head width of various
Eye length versus head width of various
The similarity of the scapes of
As was found in
This study was supported in part by the National Science Foundation under grants DEB-0743542 (awarded to JSL). We thank Gary Alpert for images and label data of specimens from Mozambique, and Brian Fisher for images and label data of specimens from Angola.