Towards a revision of the Palaearctic species of Aphodius Hellwig, 1798, subgenus Liothorax Motschulsky, 1860 (Coleoptera, Scarabaeidae, Aphodiinae) Author Angus, Robert B. 0000-0002-3860-5617 Department of Life Sciences (Insects), The Natural History Museum, Cromwell Road, London SW 7 5 BD, UK Author Maté, Jason F. 0000-0002-2505-7113 c / Henares 16, Velilla de San Antonio, Madrid, 28891, Spain Author Angus, Elizabeth M. Biomedical Imaging Unit, Level B South Block, Mail point 12, General Hospital, Southampton SO 16 6 YD, UK Author Král, David 0000-0002-7930-1927 Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ- 128 00, Praha 2, Czech Republic text ZooKeys 2024 2024-07-22 1207 205 299 journal article 10.3897/zookeys.1207.117225 94F18819-5AF5-4100-AB35-AA3C3976EE80 Aphodius ( Liothorax ) rusakovi Gusakov, 2004 Figs 2 i , 5 m , 14 c , 17 f , 20 m , n , 18 h, v , 22 p, p ’, 26 m , n Aphodius ( Liothorax ) rusakovi Gusakov, 2004: 6 . Type material examined. 2 paratypes from the Orenburg oblast’, Russia ( NHMUK ). Additional material examined. RU: 1 ♀ , Ulyanovsk , 54.056 ° N , 48.519 ° E ( ZIN ); 1 ♂ , Volgograd oblast’, 48.7 ° N , 44.5 ° E , Fastov. leg. Grebennikov. ( ZIN ). KZ or UZ 1 ♀ “ Syr-Darja. / B. v. Bodemeyer. ” ( NMP ). Differential diagnosis. A conspicuously narrow parallel-sided species, comparable with A. kraatzi but larger, length 4.5–6.5 mm and base of pronotum completely bordered by a fine impressed line, this sometimes weaker medially (Fig. 14 c ). Protibial spur of male strongly incurved apically (Fig. 18 v ). ♀ with spermatheca larger (Fig. 26 m , n ). Redescription. General appearance (Fig. 2 i ). Glossy black, length 4.7–5.5 mm , width 1.9–2.2 mm . Head fairly closely punctate, sometimes slightly rugose on the frons and anterolateral parts of the clypeus, and occasionally rugose over all except the central part of the clypeal bulge. Double punctation scarcely apparent except when the punctation is sparser on the clypeal bulge. Clypeus emarginated anteriorly, edges of this emargination bluntly rounded (head and pronotum: Fig. 5 m ). Frontoclypeal suture interrupted medially in ♀ , in ♂ sometimes with a very weak tubercle, viewed with suitable lighting (Fig. 2 i ). Epipharynx (Fig. 7 i ) with anterior margin of clithra almost straight either side of the median tylus and the mesoepitorma scarcely darkened. Prophobae rather strong, grouped towards the margins of the mesoepitorma. Chaetopedia three or four each side. Pronotum highly arched transversely, weakly so longitudinally. Entire lateral margins visible from above (Figs 2 i , 5 m ). Surface with double punctation, this often close though sometimes sparser on the disc. In some specimens the punctures are deeply impressed, so the pronotal surface does not appear smooth. Basal margin entirely bordered, the border rather heavy (Fig. 14 c ). Elytra noticeably elongate, parallel-sided. Striae narrow but rather deep, strial punctures separated by ca 4 × their diameters. Interstices 6–8 × the width of the striae, with distinct sparse fine punctation and fine reticulation (Fig. 17 f ). Apex bluntly rounded. Metaventrite (Fig. 20 m , n ) with median diamond- shaped plate fairly strongly punctate and no obvious sexual dimorphism. Legs with longer spur of mid tibiae slightly longer than the basal segment (Fig. 18 h ), and in males the spur of the anterior tibiae is distinctly hooked (Fig. 18 v ). Aedeagus (Fig. 22 p, p ’) length ca 1.1 mm , parameres relatively short and blunt-ended, somewhat downturned apically. Endophallus with scales but no hairs or bristles. Remarks. Distributed mainly in southern Russia , Ukraine , and Kazakhstan (Fig. 29 b, c ). Gusakov (2004) lists the holotype and 14 paratypes as having been collected in a dried-out rivulet at Ilek, 120 km SSW of Orenburg on the southern Urals, with two further paratypes from the Rostov and Kharkov districts of Ukraine and four more from the Temirsky region and Uralsk oblast’ in Kazakhstan The Ulyanovsk specimen ( ZIN ) is labelled as having been taken in a damp saline area (solonchak).