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Species: Tetramorium ibycterum   Bolton, 1979 

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Taxonomic History (provided by Barry Bolton, 2020)

Tetramorium ibycterum Bolton, 1979 PDF: 148, fig. 26 (w.) MADAGASCAR. Malagasy. AntCat AntWiki HOL


  Geographic regions (According to curated Geolocale/Taxon lists):
    Africa: Madagascar
  Biogeographic regions (According to curated Bioregion/Taxon lists):

Taxonomic Treatment (provided by Plazi)

Treatment Citation: Bolton, B., 1979, The ant tribe Tetramoriini (Hymenoptera: Formicidae). The genus Tetramorium Mayr in the Malagasy region and in the New World., Bulletin of the British Museum (Natural History) Entomology 38, pp. 129-181

Tetramorium ibycterumHNS sp. n.

(Fig. 26)

Holotype worker. TL 2.5, HL 0.64, HW 0.61, CI 95, SL 0.43, SI 70, PW 0.44, AL 0.68.

Mandibles with delicate sculpture resembling feeble shagreening, not longitudinally striate. Anterior clypeal margin with a median impression or notch. Frontal carinae strongly developed and surmounted by a narrow rim or flange, forming the dorsal margin of a shallow but conspicuous broad scrobe. The scrobe is bounded ventrally by a feeble longitudinal carina, running above the eye, which also forms the posterior boundary of the scrobal area. Dorsal alitrunk in profile evenly convex, without trace of metanotal groove. Propodeal spines stout and acute, metapleural lobes triangular. Shape of pedicel segments as in Fig. 26, the petiole in dorsal view very slightly broader than long, the postpetiole conspicuously so. Dorsum of head finely but irregularly longitudinally rugulose with very feeble traces of a reticulum occipitally, the interspaces with very faint ground-sculpture. Dorsal alitrunk finely reticulate-rugulose, the meshes tending to be more conspicuous on the pronotum. Petiole and postpetiole with the faintest traces of ground-sculpture dorsally, almost smooth. Gaster unsculptured. Short fine hairs present on dorsum of head but almost wholly confined to the dorsal surface of the frontal carinae. Longer fine, erect hairs present on dorsal alitrunk but very sparse, pronotum with 2 pairs, mesonotum with 1 pair, propodeum with 2 pairs in holotype, all located laterally where the dorsum meets the sides. Petiole, postpetiole and first gastral tergite without hairs, but the last with very fine appressed pubescence. Colour uniform light orange-brown.

Figs 17 - 29 TetramoriumHNS workers. 17 - 27. Head and / or alitrunk of (17, 18) isectumHNS, (19) zenatumHNS, (20) electrumHNS, (21) coillumHNS, (22, 23) anodontionHNS, (24) dysalumHNS, (25) ranarumHNS, (26) ibycterumHNS, (27) plesiarumHNS. 28, 29. Outline shape of petiole node in (28) caldariumHNS and allies, (29) scytalumHNS. Pilosity omitted from heads and from Figs 28 to 29.

Holotype worker, Madagascar: Cote Ouest, Jangoa, degraded for. litter, 18. i. 1966 (J-M. Betsch) (MCZ, Cambridge).

In the ranarum-group ibycterumHNS is unique in lacking any trace of pilosity on the first gastral tergite, and in this respect it resembles the cognatum-complex in the schaufussi-group. However, the shape of the petiole node and the presence of sculpture on the mandibles indicate that the true affinities of ibycterumHNS lie with ranarumHNS and its allies.

Specimen Habitat Summary

Found most commonly in these habitats: 33 times found in rainforest, 7 times found in tropical dry forest, 3 times found in littoral rainforest, 1 times found in transition humid forest, 1 times found in tropical dry forest on Tsingy, 2 times found in disturbed dry forest, 1 times found in degraded forest.

Found most commonly in these microhabitats: 27 times sifted litter (leaf mold, rotten wood), 9 times ex rotten log, 6 times sifted litter, 1 times under rootmat, litter on rock, 1 times ex dead twig above ground, 1 times litter.

Collected most commonly using these methods: 9 times MW 25 sample transect, 5m, 6 times MW 50 sample transect, 5m, 4 times 9 MaxiWinks, mixed samples, 3 times 10 MaxiWinks, mixed samples, 1 times 8 maxi winks, 2 times MW 75 sample transect, 5,10m, 1 times 7 MaxiWinks, 4 times 3 MaxiWinks, mixed samples, 1 times 5 MaxiWinks, mixed samples, 2 times Malaise trap, 1 times pitfall trap, PF 50 traps, 11 cm dbh with water, soap, formalin, nonlinear placement, ...

Elevations: collected from 8 - 865 meters, 407 meters average

Type specimens: Holotype: casent0172830

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