Dienerella katarzynae, Plewa & Rücker, 2020

Plewa, Radosław & Rücker, Wolfgang H., 2020, A new species of Dienerella Reitter, 1911 from Kazakhstan, with an updated checklist of Dienerella species and summary of their distribution (Coleoptera: Latridiidae: Latridiinae), Zootaxa 4722 (1), pp. 50-58 : 50-58

Dienerella katarzynae sp. nov.

( Figs. 1 A–C, 2A)

Type material. Holotype: ♂, “ South Kazakhstan, 43°15’03”N 74°49’43”E, 797 m a.s.l., Zhambyl environs, 25 km N of Korday, Kyzyltas ad Alga , 01.05.2018, under bark of Acer negundo L., leg. Radosław Plewa ”; “ Latridiidae , Dienerella katarzynae sp. nov., det. W. H. Rücker & R. Plewa, 2019” [second label surrounded by a red border] ( MIZ) . Paratypes: 4 ♂ and 9 ♀, with the same label data as the holotype; all paratypes marked with a red border (4 ♂ and 7 ♀ — FRI, 2 ♀ — WRCN) .

Description. Body length: 1.22–1.57 mm (n = 14). Glabrous body, elongated, flat, yellow-brown ( Fig. 1A ). The edges of the pronotum are slightly blackened. Legs yellow-orange, slightly brighter than other parts of the body.

Head trapezoidal in shape, the width-to-length ratio is 1:0.75, with a wedge-shaped indentation at the base. Eyes composed of six facets, temples rounded, length 0.07 mm, the edge of the eyes protruding slightly beyond the outline of the head and temples; the eye length equal to 0.75 x the length of the temples. Punctation of the head irregular, with large punctures not touching each other. Antennae pubescent, with 11 antennomeres, about 0.31 mm long ( Fig. 1B ); scape irregularly rounded, with small grooves; pedicel half the size of the scape and slightly elon- gated; antennomeres 3–11 covered with bright yellow hairs. The last three antennomeres form an extended club and the apical antennomere is the largest.

Pronotum only slightly cordate, with rounded sides ( Fig. 2A ), the width-to-length ratio is 1:0.73, without hair, with small denticles on the edges. The whole upper surface of the pronotum with slight tubercules (when viewed from the side, the entire surface of the pronotum is not even). In the posterior half of the pronotum, one round, slight indentation (not touching the lower edge of the pronotum). Anterior angles of the pronotum slightly rounded. Punctation of the pronotum irregular, comprising large dots that do not touch each other. Scutellar shield trapezoid.

Elytra without hair, together rounded. The elytra width-to-length ratio is 1:2.30. Each elytron with eight rows of dots, 25-27 dots in each row. First, third and fifth elytral intervals slightly raised along the entire length of the elytra; the 7 th elytral interval is the most convex, raised along the entire length of the elytra (most erect at the base of the elytra). The edge of the elytra is smooth, slightly blackened in the basal part.

Sexual dimorphism. No sexual dimorphism was observed except for a tiny sharp thorn at the distal end of all tibiae in males; females without distinct characteristics.

Aedeagus. Length: 0.33 mm. Very thin and translucent, narrow, pointed at apex ( Fig. 1C ). Note: in this species group within the subgenus Dienerella (s. str.) the aedeagus is not suitable for species identification.

Habitat. Local small forest ( Fig. 3A ) in the valley of the River Akchechek [Akчeчek], formed by tree species growing in moist habitats, i.e., poplar ( Populus sp. L.), willow ( Salix sp. L.), Zelkova sp. Spach and ash-leaved maple ( Acer negundo L.).

Biology. Mycetophagous species, found under the bark of a declining ash-leaved maple A. negundo (diameter = ca. 15 cm) ( Fig. 3B ). D. katarzynae sp. nov. was collected from dead cambium of the host tree. Slime moulds (Mycetozoa) were observed on the beetles analyzed.

Distribution. Known from the type locality; endemic to southern Kazakhstan. The population is isolated in the valley of the River Akchechek, surrounded by extensive steppes ( Fig. 3A ).

Etymology. The species name is derived from Katarzyna, the name of the senior author’s wife.

Differential diagnosis: Broadly rounded edges of the pronotum are the characteristics distinguishing D. katarzynae sp. nov. from three other morphologically similar taxa: D. beloni ( Reitter, 1882) , D. pilifera ( Reitter, 1875) and D. elegans ( Aubé, 1850) . In addition, in the group of the species listed, only D. katarzynae sp. nov. have no hairs on the elytra and pronotum surface.

Due to the morphological similarities in the aforesaid species of the genus Dienerella , we present a key for identification of four mostly related taxa:

1. Elytra with fine, silky and protruding hairs................................................................. 2

- Elytra without hairs or with hairs indistinct, very short........................................................ 3

2. Body length 1.50–1.60 mm; pronotum in front of base without transverse indentation ( Fig. 2B )................................................................................................. Dienerella beloni ( Reitter, 1882) distribution: Europe—introduced from Asia, Africa or Neotropics—so far found only in Belgium, Italy (Sardinia) and the Neth- erlands; Asia—Hong Kong, Japan; Afrotropical and Neotropical realms ( Rücker 2018).

- Body length 1.35–1.45 mm; pronotum almost square, slightly narrower towards the rear ( Fig. 2C ).............................................................................................. Dienerella pilifera ( Reitter, 1875) distribution: Europe: France, Greece, Italy, Austria and Spain; Asia: Japan; North Africa: Algeria, Canary Islands, Madeira Archipelago, Morocco and Tunisia ( Rücker 2018).

3. Body length: 1.30–1.50 mm. Pronotum as long as broad, lateral margins converging towards the rear ( Fig. 2D ); elytra with extremely short hairs........................................................ Dienerella elegans ( Aubé, 1850) distribution: Europe: Armenia, Great Britain, France, Greece, Italy, Malta, Austria, Poland, Sweden, Switzerland, Spain, Ukraine, Hungary, Belarus; Asia: Israel, Japan, Tajikistan; North Africa: Algeria, Madeira Archipelago; Afrotropical and Ne- arctic realms ( Rücker 2018).

- Body length: 1.22–1.57 mm. Pronotum broadly rounded, only slightly cordate, one third of sides rounded, broader than long ( Fig. 2A ); pronotum and elytra without hairs........................................ Dienerella katarzynae sp. nov. distribution: Asia: southern Kazakhstan.

Figures

FIGURE 1. Dienerella katarzynae sp. nov., holotype (male):A habitus, dorsal view (body length: 1.36 mm); B antenna (length: 0.31 mm); C aedeagus, lateral view (length: 0.33).

FIGURE 2. Pronota of A Dienerella katarzynae sp. nov. (holotype); B D. beloni (Reitter, 1882); C D. pilifera (Reitter, 1875); D D. elegans (Aubé, 1850).

FIGURE 3. Dienerella katarzynae sp. nov.: A Type locality—small deciduous forest; B Detailed view of the host plant (ashleaved maple—Acer negundo L.).