Tychobythinus monoceros ( Normand, 1932 ) Besuchet & Cuccodoro & Sabella & Ch- & Ch-, 2013

Besuchet, Claude, Cuccodoro, Giulio & Sabella, Giorgio, 2013, On the genera Acanthobythus Normand, 1930 and Ceratobythus Normand, 1932 (Coleoptera: Staphylinidae: Pselaphinae), Revue suisse de Zoologie 120 (2), pp. 271-280 : 276-279

Tychobythinus monoceros ( Normand, 1932) comb. nov. Figs 5-7

Bythoxenus (Ceratobythus) monoceros Normand, 1932: 16 , figs 2-3 (head dorsal and lateral view).

Ceratobythus monoceros . – Jeannel, 1956: 64, fig. 58 (habitus).

TYPE MATERIAL: Holotype, Northeastern Algeria, Bejaia province; male, Adekar ( Soummam ), X.1931 (H. Normand) ( MHNG).

REDESCRIPTION: Body (Fig. 5) 1.50 mm long, uniformly pale brown-reddish; wingless and anophthalmous. Pubescence fairly uniform, slightly longer on anterior portion of elytra and denser on pronotum, consisting of setae distant from each other by slightly less than their length, slightly arcuate and semi-erect to recumbent, predominantly slightly longer than apical width of metafemora (0.06 mm); presence of several much longer setae on head, pronotum and elytra; each tergite with a pair of long discal setae.

Head (Fig. 6) with pair of 0.07 mm long longitudinally compressed antennal lobes extended each ventrally with short spine bearing 3 tufts of short setae; antennal lobes separated by conspicuous mediodorsal conical horn-like process (length 0.10 mm) obliquely projecting anterad and bearing at tip curved seta 0.42 mm long, (broken off the holotype by dissection). Frons deeply depressed, margined with sharp ridge almost to round tempora and bearing short additional medial process with two diverging tufts of aggregated setae. Occipital region slightly convex with long medial occipital carina reaching anterior edge of vertexal foveae. Tempora each with a long seta curved anterad. Antennae 0.80 mm long with scapus 5 times as long (0.25 mm) as wide (0.05 mm) and antennomere II oval (length 0.09 mm; width 0.05 mm wide). Maxillary palpi with segment I almost indistinct; II (length 0.22 mm; width 0.02- 0.04 mm) somewhat curved and gradually enlarged from base to apex, with posterior surface covered with tubercles distant from each other by slightly more that their diameter; III (0.05 mm / 0.04 mm) fairly oval bearing a few tubercles; IV (0.24 mm / 0.07 mm) securiform and finely pubescent. Gular region rather broad, gently convex and bearing two minute tubercles.

Pronotum wider (0.33 mm) than long (0.30 mm), almost spherical, narrower anteriorly than posteriorly, with maximal width slightly anterior middle; antebasal sulcus well-marked, joining lateral foveae. Disc almost smooth in middle and covered laterally with low tubercles separated from each other by 3-4 times their diameter.

Elytra wider (0.54 mm) than long (0.50 mm), more convex transversely than longitudinally; pair of deep basal elytral foveae, internal fovea joint to complete sutural stria, and external fovea extended by rather wide and deep depression reaching at most

FIG. 5 Dorsal habitus of Ceratobythus monoceros , holotype, frontal macroseta broken. Scale bar 1 mm.

FIGS 6-7

Ceratobythus monoceros , holotype. (6) Head, dorsal view. (7) Aedeagus, dorsal view. Scale bar 0.1 mm.

elytral mid-length; subhumeral elytral fovea extended dorsally by short vertical carina, ventrally by entire lateral carina.

Metasternum with lateral mesocoxal and lateral metasternal foveae deep and tomentose.

Abdomen rather short (0.45 mm).

Legs with trochanters simples; anterior edge of protrochanters with 3-4 small prominent tubercles; metatrochanters much longer than mesotrochanters. Profemora relatively robust (0.44 mm / 0.10 mm), each bearing row of 8 small tubercles on basal third of anterior margin, first 3-4 much more prominent than others, larger than wide; mesofemora (0.45 mm / 0.08 mm) and metafemora (0.51 mm / 0.06 mm) more slender. Protibiae (0.40 mm / 0.05 mm) and mesotibiae (0.40 mm / 0.05 mm) straight; metatibiae (0.55 mm / 0.05 mm) somewhat curved subapically.

Male: Aedeagus (Fig. 7), 0.27 mm long, with parameres slender in apical portion and inter-crossed subapically, without denticles on outer margin; internal sac with 11 thin and slender sclerites.

Female: Unknown.

8

FIGS 8-9

(8) Left lateral view of head and pronotum of Acanthobythus araneipes , lectotype. (9) Ceratobythus monoceros , holotype, frontal macroseta broken. Scale bar 0.5 mm.

COMMENTS: Within Tychobythinus , the presence of a conspicuous frontal horn is unique to T. monoceros .

Normand (1932) specified that he found only one specimen in a bag of clay soil at the foot of a bank. He observed that while moving, it was touching the soil with the antennae, while his long frontal sensory seta was apparently used to detect obstacles.

According to Jeannel (1956: 64) the holotype was a female.