Monomorium exiguum Forel, 1894

Sharaf, Mostafa R., Collingwood, Cedric A., Al Dhafer, Hathal M., Al mutairi, Mohammed S. & Aldawood, Abdulrahman S., 2015, New synonyms of two Arabian ants of the genus Monomorium Mayr, 1855 (Hymenoptera, Formicidae), ZooKeys 505, pp. 51-58 : 52

Taxon classification Animalia Hymenoptera Formicidae

Monomorium exiguum Forel, 1894 Figs 1-4

Monomorium exiguum For full synonymy see Heterick (2006), pp. 115-116.

Monomorium exiguum Forel, 1894: 85. (lectotype worker) Ethiopia. Afrotropic. "Ethiopia, Sudabessinien." (MHNG), http://www.antweb.org/specimen/CASENT0101870 [Image of type specimen examined].

Monomorium desertorum Collingwood & Agosti, 1996: 344 (w.) Saudi Arabia. Afrotropic." (WMLC), http://www.antweb.org/specimen/CASENT0906343. Syntype worker [examined], Syn. n.

Material examined.

Saudi Arabia, Baha, Dhi Ayn Archeological Village, 18.v.2010, 20.132°, 41.004°, 741m, (M. R. Sharaf, leg.) (21); Saudi Arabia, Riyadh, Oyaina, 28.iv.2010; 25.011°, 46.493°, 749m, (M. R. Sharaf, leg.) (3); Saudi Arabia, Riyadh, Qarina Valley, 5.xi.2009, 25.273°, 46.289°, 761m, (M. R. Sharaf, leg.) (3); Saudi Arabia, Baha, Dhi Ayn Archeological Village, 20.ix.2011, 20.132°, 41.004°, 744m, (M. R. Sharaf, leg.) (10); Saudi Arabia, Almajardah, wadi Khat, 10.xi.2012, 19.001°, 41.016°, 513m, (M. R. Sharaf, leg.) (6); Saudi Arabia, wadi Shahdan (Jizan), 13.xi.2012, 17.472°, 42.856°, 200m, (M. R. Sharaf, leg.) (8); Saudi Arabia, Wadi Aljora near Abadan, 12.xi.2012, 17.005°, 43.001°, 465m, (M. R. Sharaf, leg.) (6); Saudi Arabia, Baha, Wadi Elzaraeb, 9.v.2011, 20.073°, 41.387°, 2086m, (M. R. Sharaf, leg.) (1); Saudi Arabia, Abu Arish, 10.iv.2012, 17.013°, 42.802°, 90m, (M. R. Sharaf, leg.) (6); Saudi Arabia, Dhi Ayn Archeological Village, 11.v.2011, 19.929°, 41.442°, 741m, (M. R. Sharaf, leg.) (3); Saudi Arabia, Baha, Dhi Ayn Archeological Village, 7.iv.2013, 19.929°, 41.442°, 744m, (M. R. Sharaf, leg.) (4); Saudi Arabia, AlUrdiyah gov., Wadi Gonouna, 12.v.2011, 19.429°, 41.605°, 353m, (M. R. Sharaf, leg.) (20); Saudi Arabia, Al Bahah, Wadi Turabah, AlMandaq, 14.v.2011, 20.211°, 41.288°, 1793m, (M. R. Sharaf, leg.) (7); Saudi Arabia, Dhi Ayn Archeological Village, 15.v.2011, 19.929°, 41.442°, 741m, (M. R. Sharaf, leg.) (1); Saudi Arabia, Al Bahah, Wadi Turabah, AlMandaq, 10.v.2011, 20.211°, 41.288°, 1793m, (M. R. Sharaf, leg.) (1); Saudi Arabia, Riyadh, Hawtet Bani Tamim, 20.i.2014, 23.480°, 46.844°, 597m, (M. R. Sharaf, leg.) (3); Saudi Arabia, Al Qatif, El Naft, 23.iii.2012, 26.510°, 49.969°, 30m, (M. R. Sharaf, leg.) (2); UAE, Khor al-Khwair, 25.57.56.03, 8.iii.2007, (M. Hauser et al.) (1); UAE, Sharjah, 25.21.55.24, 28. ii– 12.iv.2011, (M. Hauser et al.) (1); UAE, Wadi Bih dam, 25.48.56.04, 16-31.xii.2009, (M. Hauser et al.) (1).

Remarks.

Only a single paratype specimen with the same data as the holotype exists at WMLC. The holotype and other paratypes are considered lost.

The description of Monomorium desertorum in Collingwood and Agosti’s (1996) indicated that the eyes are located anterior to the midlength of head, the scapes when retracted back do not reach the posterior margin of head, the antennae are 11 segmented, and the body is not sculptured except for the metanotal cross-ribs. Comparison was made of the single available paraype worker of Monomorium desertorum with the lectotype worker of Monomorium exiguum was carried out. We here treat Monomorium desertorum as a junior subjective synonym of Monomorium exiguum .

Habitat.

The vast majority of Monomorium exiguum nests that were collected in KSA were found to be associated with leaf litter and topsoil layers where workers foraged. Frequently nests were directly in the soil. The nesting habits of Monomorium exiguum however, are diverse. In a site located in the southwestern mountains of the KSA, the species was found nesting in loose sandy soil with high moisture content and among roots of small Portulaca oleracea L. ( Portulacaceae ) plants beneath a date palm tree, Phoenix dactylifera L. ( Arecaceae ). Several worker series were nesting in a humid clay soil under banana trees. Other worker series were collected under a rock next to Juniperus procera Hochst. ex Endlicher ( Cupressaceae ) and Acacia spp. ( Mimosaceae ) trees. Another nest was found in thick layer of leaf litter under a large and old Ficus benghalensis L. ( Moraceae ) tree where the soil was rich in decayed organic matter. Some nests were found in leaf litter under Calotropis procera (Aiton) W.T.Aiton ( Asclepiadaceae )and next to a mango tree ( Mangifera sp., Anacardiaceae ).