This ant is one of several species in the M. rubriceps species-complex that are known from one or a few collections only. This ant, like others in the species-complex, nests in wood. (Heterick 2001)
Heterick (2001) - A member of the rubriceps group. The appearance of M. nightcapense is very similar to that of Monomorium rubriceps, but the eye is large and the alitrunk is smooth and bare of sculpture.
Keys including this Species
Distribution based on Regional Taxon Lists
Distribution based on AntMaps
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The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.
- nightcapense. Monomorium nightcapense Heterick, 2001: 433, fig. 42 (w.) AUSTRALIA.
Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.
Holotype. HML 3.10; HL 1.08; HW 0.98; CeI 90; SL 0.92; SI 94; PW 0.64. Others. HML 2.92-3.23; HL 0.98-1.08; HW 0.88-0.98; CeI 88-91; SL 0.81-0.91; SI 93-96; PW 0.55-0.61 (7 measured).
As for the worker of Monomorium rubriceps, but with the following apomorphies.
Head. Head square or rectangular; vertex planar; frons smooth and shining with combination of incurved decumbent and subdecumbent setulae and erect and suberect setae. Compound eyes circular or subcircular, or elliptical; eye large, eye width greater than 1.5x greatest width of antennal scape. Anteromedial clypeal margin straight or slightly emarginate, median clypeal carinae not produced as teeth or denticles. Mandibles (viewed from front) triangular and smooth, with piliferous punctures.
Alitrunk. Promesonotal sculpture absent, promesonotum smooth and shining; setulae decumbent and subdecumbent. Metanotal groove present as feebly impressed furrow between promesonotum and propodeum. Propodeal sculpture absent; propodeum smooth and shining; dorsal propodeal face flattened; processes absent (propodeum smoothly rounded in profile or with slight hump at propodeal angle). Declivitous face of propodeum flat. Erect and suberect propodeal setae > 5.
Petiole and postpetiole. Petiolar node tumular and inclined posteriad. Ratio of greatest node breadth (viewed from front) to greatest node width (viewed in profile) near 1: 1. Anteroventral process always absent or vestigial. Height-length ratio of postpetiole near 4:3 to near 1:1. Ventral process vestigial.
General characters. Colour of most of head capsule brown, mandibles and surrounding part of head, alitrunk, petiole, postpetiole, and appendages amber, anterior sector of first gastral tergite yellow, remainder of gaster dark brown. Worker caste monomorphic.
Holotype. Worker (top point), New South Wales, Blue Knob, Mt Nightcap Ra., 5.ix.l966, B. B. Lowery, rainforest, 3000 ft., ANIC ants vial 1.147 (Australian National Insect Collection). Paratypes. New South Wales: 2 + 3 workers with same data as the holotype (ANIC, The Natural History Museum); 5 workers and 1 ergatoid, same collection details as holotype, additional data: “in centre of large moss-covered branch, A211” [ants on this pin wrongly identified as M. kilianii] (Museum of Comparative Zoology).
- Holotype, worker, Blue Knob Mt., Nightcap Range, New South Wales, Australia, Lowery,B.B., ANIC32-015673, Australian National Insect Collection.
- Paratype, 3 workers, Blue Knob Mt., Nightcap Range, New South Wales, Australia, Australian National Insect Collection.
- Paratype, 3 workers, Blue Knob Mt., Nightcap Range, New South Wales, Australia, The Natural History Museum.
- Paratype, 5 workers, 1 ergatoid queen, Blue Knob Mt., Nightcap Range, New South Wales, Australia, Museum of Comparative Zoology.
Named after the Nightcap Ranges.
- Heterick, B. E. 2001. Revision of the Australian ants of the genus Monomorium (Hymenoptera: Formicidae). Invertebrate Taxonomy. 15:353-459. PDF (page 433, fig. 42 worker described)