Delenda Croissandeau, 1891

Bekchiev, Rostislav & Brachat, Volker, 2014, Revision of the genus Delenda Croissandeau, 1891 (Coleoptera: Staphylinidae: Pselaphinae), Zootaxa 3765 (6), pp. 583-592 : 584

Delenda Croissandeau, 1891

Delenda Croissandeau, 1891 . Type species: Delenda carthago Croissandeau, 1891 , monotypy. Delenda Croissandeau : Raffray, 1904: 500 (synonymy of Eusonoma Reitter ); Raffray, 1911: 7 (catalogue); Newton & Chandler, 1989: 18 (catalogue).

Eusonoma Reitter, 1893: 172 . Type species: Eusonoma frivaldszkyi Reitter, 1893 , monotypy.

Redescription. Habitus as in Fig. 1; length 1.5 – 1.7 mm; body relatively flat, covered with short, suberect golden setae. Head ( Fig. 2 a) wider than long (0.28 – 0.34 / 0.20 – 0.28mm) with two deep vertexal foveae; frontal sulcus large and triangular, opened on frontal rostrum, which is slightly extended and rounded anteriorly; antennal tubercules small. Antennae ( Fig. 2 b) with eleven antennomeres; scape longer than wide (0.09 – 0.1/ 0.048 – 0.05 mm); pedicel longer than wide (0.06/ 0.05 mm); III as wide as long (0.03/ 0.03 mm); IV longer than wide (0.04/ 0.03 mm); antennomeres V–VII equal in size, wider than long (0.04/ 0.04 mm); antennal club 3-segmented, welldefined. Each eye composed of about 10 – 30 facets. Maxillary palpi ( Fig. 2 c) with palpomeres I short, II lengthily pedunculate, III small, IV large and oval. Labrum ( Fig. 3 ) species characteristic; with few setae. Pronotum ( Fig. 4 a) wider than long (0.32 – 0.38 / 0.24 – 0.30 mm), widest part situated anterior to middle; pronotal disc at middle with large flat area, with five elongate, shallow depressions, two in anterior part, and three in posterior part; lateral antebasal foveae deep, not connected by antebasal sulcus; basolateral foveae present, and connected by a fine sulcus. Prosternum ( Fig. 4 b) with median and lateral procoxal foveae. Mesoventrite ( Fig. 4 c) with median mesoventral fovea, and deep lateral mesoventral foveae, with lateral mesocoxal foveae. Metaventrite with lateral metaventral foveae. Elytra ( Fig. 5 a) very short, length 0.22 – 0.26 mm, with width at base (0.34 – 0.48 mm); each elytron lacking basal foveae, with two discal foveae; sutural stria incomplete; without discal stria. Abdomen ( Fig. 5 b, c) length 0.93 – 1.02 mm; first three visible tergites (IV–VI) wider than long (0.44 – 0.50/ 0.18 – 0.20 mm), without any trace of foveae or carinae; first three visible sternites (IV–VI, each with two basolateral foveae. Legs short and robust, metacoxae ( Fig. 5 d) with deep fovea on external border. All known species are wingless. Aedegus ( Fig. 6 ) with median lobe thin and asymmetrical, parameres well-developed and symmetrical, located on large tooth of basal part of median lobe.

Sexual dimorphism. Not apparent. The penial plate (sternite IX) of the male ( Fig. 5 b) is oval and long, while the female lacks this modification ( Fig. 5 c).

Biology. S pecies of the genus are always collected by sifting leaf-litter in mesophilous Fagus sylvatica L. forests, with Rhododendron ponticum L. or Platanus orientalis Mill. ( Fig. 7 a) present, and from xerophilous forests of Quercus spp., and Caprinus orientalis Mill. , ( Fig. 7 b).

Distribution. Bulgaria, Turkey ( Fig. 8 )

Relationships. Delenda is a very peculiar genus that can be readily separated from other genera of Faronitae by the following combination of characters: head with large triangular sulcus; antennae with well-formed terminal club; elytra very short, with only two discal foveae, sutural stria incomplete; metacoxa with fovea. A relationship with Faronus Aub, 1844 could be possible, since both genera share a fovea on the metacoxae, but this is the only shared, excluding the common characters typical for Faronitae, character between them. These fovea are missing in some other genera of Faronitae such as Sonoma Casey, 1886 , Golasa Raffray, 1904 and Golasina Jeannel, 1962 (Kurbatov pers. comm). Aside from this possible affinity to Faronus , Delenda appears to be an isolated genus in the supertribe without clear relationships to any other known genus of Faronitae.

Figures

FIGURE 2. Head of Delenda sp.: a) head, dorsal view (scale — 0.2 mm): b) antenna (scale — 0.2 mm); c) maxillary palp (scale — 0.1 mm).

FIGURE 3. Labrum of Delenda species (dorsal view, scale — 0.1 mm): a) D. carthago; b) D. frivaldszkyi; c) D. rhodopensis sp. n.

FIGURE 4. Pronotum of Delenda (scale — 0.15 mm): a – b) pronotum — dorsal and ventralview; c) meso and metaventrite. Abbreviations: laf — lateral antebasal foveae; blf — basolateral foveae; lpcf — lateral procoxal fovea; mpcf — median procoxal fovea; lmcf — lateral mesocoxal fovea; lmtf — lateral metaventral fovea; lmsf — lateral mesoventral fovea; mmsf — median mesoventral fovea.

FIGURE 5. Elytra, abdomen (scale — 0.5 mm) and metacoxa (scale — 0.1 mm) of Delenda: a) elytra, dorsal view; b) abdomen, male, ventral view; c) abdomen, female, ventral view; d) metacoxa, ventral view. Abbreviations: def — discal elytral fovea; ss — sutural stria; blf — basolateral fovea.

FIGURE 6. Aedeagi of Delenda species, lateral, right view (scale — 0.1 mm): a) D. carthago; b) D. frivaldszkyi; c) D. rhodopensis sp. n.

FIGURE 7. Habitats of Delenda: a) Bulgaria, Strandzha Mts., Marina reka River, Fagus forest with undergrowth of R. ponticum; b) Bulgaria, East Rhodopes, Bial Gradets Village, Caprinus bushes, type locality of D. rhodopensis sp. n.

FIGURE 8. Distribution of Delenda species: blue dots — D. carthago; green — D. frivaldszkyi; red — D. rhodopensis sp. n.