Description
Male: Body dark brown (Fig. 1a); pubescent with short, golden semierect setae and some long, erect setae. Length 1.10-1.19 mm. Head (Fig. 1b) wider than long (0.25/0.20 mm), covered with dense, semierect setae. Frontal rostrum distinctly wider than long (0.13/0.07 mm); antennal tubercles well-developed, median depression shallow. Vertex convex, with distinct median ridge. Ventral side of the head with narrow and deep depression in gular region, the depression distinctly longer than wide, shining; anterior border of depression carinate, with two obtuse teeth; posterior border simple, with one thick and long seta. Eyes well developed, each composed of 10-12 ommatidia. Maxillary palpi long (Fig. 1b), almost as long as antennae, palpomeres II–III granular, palpomeres IV with dense, short and recumbent setae. Antennae (Fig. 1b) short – 0.43-0.44 mm; scapes longer than wide (0.09-0.1/0.04-0.05 mm), with a small tubercule in anteromesal part; pedicel globular (0.034/0.034 mm); antennomeres III slightly longer than wide (0.025/0.022); antennomeres IV – VIII about same length (0.017/0.025 mm each); antenommeres IX wider than long (0.043/0.017 mm); antenommeres X wider than long (0.067/0.017 mm); XI longer than wide (0.12/0.068 mm). Pronotum convex (0.27/0.30 mm), widest part before middle, covered with dense, long, sеmierected setation; disk shiny; lateral antebasal foveae well-defined, connected by well-defined antebasal sulcus. Elytra wider than long (0.510/0.425 mm) each with two basal foveae, sutural stria well-defined through whole length of elytron; covered with long, golden and semierect setae, with deep and irregular punctation. Abdomen slightly narrower than elytra, covered with a long, semierect setae, first two visible tergites of same length. Legs long and slender, protibia simple, metatibia with strong spur in apical inner part.
Aedeagus as in Fig. 2, length – 0.20-0.22 mm.
Sexual dimorphism: The female is with a simple scapes, gular region of the head is without modifications, metatibia is simple.
Diagnosis
Tychobythinus oculatus sp. n. is morphologically closely related to Tychobythinus abnormipes Reitter, 1910, and Tychobythinus pauper Kiesenwetter, 1858, both from Greece, they share similar shape of the scape (longer than wide, with a small tubercule). The new species clearly differs from Tychobythinus abnormipes, and Tychobythinus pauper by the very simplified internal armature of the aedeagus (in Tychobythinus abnormipes and Tychobythinus pauper the aedeagus has a long and crossed internal aphophyses), and by the shape of the gular depression (simplified and narrow in Tychobythinus oculatus; wide and triangular in Tychobythinus abnormipes; strongly modified in Tychobythinus pauper). Tychobythinus oculatus sp.n. can be readily distinguished from Tychobythinus vignai, the only other currently known species from Turkey, by the presence of eyes (related to its way of life) and by the specific shapes of the antennae, gular region and aedeagus.