Carebara altinodus

The type material was collected from a conifer-broadleaf mixed forest.

Identification
Xu (2003) - Close to Carebara capreola, but head nearly square, only slightly longer than broad. Occiput with minute horns. Eyes present.

Distribution based on Regional Taxon Lists
Palaearctic Region: China.

Nomenclature

 * . Oligomyrmex altinodus Xu, 2003: 312, figs. 5-8 (s.w.) CHINA (Yunnan).
 * Combination in Carebara: Guénard & Dunn, 2012: 41.
 * Status as species: Guénard & Dunn, 2012: 41.

Worker
Holotype soldier. TL 3.7, HL 1.05, HW 0.95, CT 90, SL 0.50, ST 53, PW 0.58, AL 0.90, PL 0.45, PH 0.35, DPW 0.28. Head slightly longer than broad, roughly trapezoid in full face view and moderately narrowed forward. Occipital margin moderately concave. Occipital corners roundly prominent. Lateral sides slightly convex. Mandible with 5 teeth. Median portion of clypeus depressed longitudinally, bicarinate and divergent forward, anterior margin nearly straight. Antenna 11 segments with a 2-segmented club, apex of scape reached to 4/7 of the distance from antennal socket to occipital corner. Eye with 7 facets. In profile view, occiput with a pair of minute horns. Dorsum of head evenly convex. Promesonotum roundly convex. Promesonotal suture distinct. Mesonotum with a transverse furrow, posterior portion prominent and forming a transverse ridge behind the furrow. Metanotum present and tongue-like. Metanotal groove impressed. Propodeum with posterodorsal corner bluntly angled, dorsum straight and depressed longitudinally in the middle, declivity concave. Petiole pedunculated anteriorly, ventral face straight, anteroventral corner with a rightly angled tooth. Petiolar node narrow and high, anterior and posterior faces steeply sloped, dorsal face narrow and convex. Postpetiolar node roundly and anterodorsally convex, lower than petiolar node. In dorsal view, petiolar node width: postpetiolar node width = 1.0: 1.2, petiolar node transverse, postpetiolar node semicircular. Anterior border of gaster deeply concave in the middle in order to accept postpetiole.

Mandibles and median portion of clypeus smooth and shiny. Head densely and largely punctate, distance between punctures about equal to diameter of a puncture. Punctures on dorsum of head much denser. Anterior 1/3 of head longitudinally striate. Dorsum of promesonotum sparsely punctate, lateral sides of pronotum smooth and shining. Lateral sides of mesonotum, metanotum, propodeum, petiole and postpetiole densely and finely punctate. Dorsal face of petiolar node smooth and shining. Gaster sparsely and largely punctate, distance between punctures about 2-3 times of the diameter of a puncture. Head and body with dense decumbent pubescences. Frontal canna with 4 long erect hairs. Mesonotum, petiolar node, postpetiolar node and apex of gaster with sparse erect hairs. Scapes and tibiae with dense decumbent pubescences, without erect hairs. Head and gaster blackish brown, alitrunk, petiole and postpetiole reddish brown. Mandibles, antennae and legs yellow.

Paratype soldiers. TL 3.6-4.5, HL 1.00-1.08, HW 0.90-1.00, CI 90-93, SL 0.50, SI 50-56, PW 0.53-0.63, AL 0.90-1.03, PL 0.40-0.45, PH 0.33-0.38, DPW 0.25-0.30 (5 individuals measured). As holotype, but occipital horns minute to absent, posterodorsal corner of propodeum bluntly angled to rightly angled.

Paratype workers. TL 1.3-1.5, HL 0.38-0.43, HW0.35-0.38, CI 88-100, SL0.25-0.28, SI 67-79, PW 0.23-0.24, AL 0.40-0.43, PL 0.18-0.20, PH 0.15, DPW 0.09-0.10 (5 individuals measured). Similar to the holotype, but much smaller, head normal. Occipital margin weakly concave. Apex of scape reached to 5/6 of the distance from antennal socket to occipital corner. Eye with 2 facets. Occiput without horns. Promesonotum moderately convex. Promesonotal suture obsolete on the dorsum. Mesonotum without transverse furrow and ridge. Metanotum absent. Metanotal groove deeply impressed. Posterodorsal corner of propodeum rounded. Head, pronotum, petiolar node, postpetiolar node and gaster smooth and shining. Mesonotum, petiole and postpetiole without erect hairs. Head and body with short, sparse and depressed pubescences. Body yellow in color, head and gaster yellowish brown.

Type Material
Holotype. soldier, No. A1194, 1500 m, west slope of Ailaoshan, Wencha Village, Huashan Town, Jingdong County, Yunnan Province, collected in the conifer-broadleaf mixed forest by Miss Chai Zheng-Qun on 13 Apr. 2002. Paratypes: 15 soldiers and 15 workers, with same data as holotype.

References based on Global Ant Biodiversity Informatics

 * Chen Y., C.-W. Luo, H. W Li, Z. H. Xu, Y. J. Liu, and S. J. Zhao. 2011. The investigation of soil ant resources on the West slope of Mt Ailao. Hubei Agricultural Sciences 50(7): 1356-1359.
 * Fontanilla A. M., A. Nakamura, Z. Xu, M. Cao, R. L. Kitching, Y. Tang, and C. J. Burwell. 2019. Taxonomic and functional ant diversity along tropical, subtropical, and subalpine elevational transects in southwest China. Insects 10, 128; doi:10.3390/insects10050128
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Liu X. 2012. Taxonomy, diversity and spatial distribution characters of the ant family Formicidae (Insecta: Hymenoptera) in southeastern Tibet. PhD Thesis 139 pages
 * Liu X., Z. Xu, N. Yu, and C. Zhang. 2016. Distribution patterns of ant species ( Hymenoptera: Formicidae) in Galongla Mountains and Medog Valley of Southeastern Tibet. Scientia Silvae Sinicae 52(11): 88-95.
 * Lu Z., K. Li, N. Zhang, and Y. Chen. 2017. Diversity and indicator species of leaf-litter ants in Eucalyptus grandis plantations and secondary natural forests. Forest Research 29(4): 576-580
 * Lu Z., and Y. Chen. 2016. Effects of habitat on ant functional groups: a case study of Luchun County, Yunnan Province, China. Chinese Journal of Eco-Agriculture 24(5): 801-810.
 * Skarbek C. J., M. Noack, H. Bruelheide, W. Hardtle, G. von Oheimb, T. Scholten, S. Seitz, M. Staab. 2019. A tale of scale: plot but not neighbourhood tree diversity increases leaf litter ant diversity. Journal of Animal Ecology DOI: 10.1111/1365-2656.13115
 * Song Y., Z. Xu, C. Li, N. Zhang, L. Zhang, H. Jiang, and F. Mo. 2013. An Analysis on the Ant Fauna of the Nangun river Nature Reserve in Yunnan, China. Forest Research 26(6): 773-780.
 * Staab M., N. Bluthgen, and A. M. Klein. 2014. Tree diversity alters the structure of a tri-trophic network in a biodiversity experiment. Oikos doi: 10.1111/oik.01723
 * Xu Z. H. 2003. A systematic study on Chinese species of the ant genus Oligomyrmex Mayr (Hymenoptera: Formicidae). Acta Zootaxonomica Sinica 28: 310-322.
 * Xu Z. 2003. A systematic study on Chinese species of the ant genus Oligomyrmex Mayr (Hymenoptera: Formicidae) Acta Zootaxonomica Sinica 28(2): 310-322.