Monomorium atomum

In Yemen this species was found in humid leaf litter under a date palm tree where the soil was rich in accumulations of decayed animal faeces (Sharaf et al., 2017).

Identification
Worker. Small species (TL 1.20–1.30). Head distinctly longer than broad, feebly convex or parallel sides and feebly concave posterior margin; eyes small with four or five ommatidia in the longest row; petiole peduncle in profile short and without anteroventral process. Body smooth and shining. Colour uniform yellow (Sharaf et al., 2017).

Distribution based on Regional Taxon Lists
Afrotropical Region: Socotra Archipelago, Yemen. Oriental Region: Bangladesh, India.

Nomenclature

 * . Monomorium atomus Forel, 1902c: 210 (w.) INDIA (Odisha, Assam, Maharashtra, West Bengal).
 * Type-material: syntype workers (number not stated).
 * Type-localities: India: Orissa (Taylor), Assam (Smythies), Poona (Wroughton), Calcutta (Rothney).
 * Type-depository: MHNG.
 * Bingham, 1903: 208 (q.).
 * Combination in M. (Martia): Forel, 1910c: 252;
 * combination in M. (Lampromyrmex): Emery, 1922e: 183.
 * Status as species: Forel, 1903a: 687; Rothney, 1903: 97; Bingham, 1903: 208; Arnold, 1916: 239; Emery, 1922e: 183; Chapman & Capco, 1951: 163; Ettershank, 1966: 87; Pisarski, 1967: 400; Bolton, 1995b: 259; Borowiec, L. 2014: 115 (see note in bibliography); Bharti, Guénard, et al. 2016: 39; Sharaf, Fisher, et al. 2017: 20.
 * Distribution: Afghanistan, India, Yemen.
 * Current subspecies: nominal plus aharonii, cooperi, integrium, procax.

Description
Worker

Bingham (1903): Pale yellow, the legs a shade paler than the liead and thorax ; entirely smooth, polished and shining : pilosity sparse, on the scape of the anteinne and tibiae of the legs oblique. Head a little broader posteriorly than in front, the posterior border slightly emarginate ; mandibles narrow, the masticatory margin with 4 teeth, maxillary palpi l-jointed ; Clypeus slightly convex, the carinae strongly convergent above, obtuse ; antennae 11-jointed, very short, the scape not nearly attaining the posterior margin of the head ; eyes placed below the middle of the side of the head. Thorax : the pro-raesonotum very convex, meso-metanotal suture deeply impressed, the thorax constricted at the suture and in profile emarginate above ; basal portion of metanotum rectangular, a very little longer than broad. Pedicel : the nodes from above subequal, globose, the 1st node anteriorly petiolate ; abdomen oval.

Length: ~ 1.5 (1.2 - 1.3) mm

Queen

See M. atomum integrium

References based on Global Ant Biodiversity Informatics

 * Borowiec L. 2014. Catalogue of ants of Europe, the Mediterranean Basin and adjacent regions (Hymenoptera: Formicidae). Genus (Wroclaw) 25(1-2): 1-340.
 * Forel A. 1902. Myrmicinae nouveaux de l'Inde et de Ceylan. Rev. Suisse Zool. 10: 165-249.
 * Forel A. 1903. Les Formicides de l'Empire des Indes et de Ceylan. Part X. J. Bombay Nat. Hist. Soc. 14: 679-715.
 * Pisarski B. 1967. Fourmis (Hymenoptera: Formicidae) d'Afghanistan récoltées par M. Dr. K. Lindberg. Annales Zoologici (Warsaw) 24: 375-425.
 * Tak N. 1995. Studies on ants (Formicidae) of Rajasthan - 1 Jodhpur. Hexapoda 7(1): 17-28.
 * Tak N. 2008. Ants of Rajasthan. Conserving Biodiversity of Rajasthan Zool. Surv. India. 149-155.
 * Tak N. 2009. Ants Formicidae of Rajasthan. Records of the Zoological Survey of India, Occasional Paper No. 288, iv, 46 p
 * Tak N., and N. S. Rathore. 1996. Ant (Formicidae) fauna of the Thar Desert. Pp. 271-276 in: Ghosh, A. K.; Baqri, Q. H.; Prakash, I. (eds.) 1996. Faunal diversity in the Thar Desert: gaps in research. Jodhpur: Scientific Publishers, xi + 410 pp.
 * Tak, N. 2009. Ants (Hymenoptera: Formicidae) of the Thar Desert of Rajasthan and Gujarat. in C. Sivaperuman et al. (eds.), Faunal Ecology and Conservation of the Great Indian Desert
 * Varghese T. 2004. Taxonomic studies on ant genera of the Indian Institute of Science campus with notes on their nesting habits. Pp. 485-502 in : Rajmohana, K.; Sudheer, K.; Girish Kumar, P.; Santhosh, S. (eds.) 2004. Perspectives on biosystematics and biodiversity. Prof. T.C. Narendran commemoration volume. Kerala: Systematic Entomology Research Scholars Association, xxii + 666 pp.