Espeson adisi, Irmler, 2012

Irmler, U., 2012, The Neotropical species of the genera Pseudespeson L, 1994 and Espeson S, 1882 (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 62 (2), pp. 331-360 : 336

Espeson adisi n. sp. ( Figs 6 a-e, 16A)

Type material:

Holotype, male: Brazil: Amazonas , Manaus, male, floating meadow, #WM13, 15.4.1981, leg. J. Adis ( INPA).

Paratypes: floating meadow, 13 specimens, #WM13, #WM12, 15.4.1981, 3 specimens, #WM10, 6.2.1981, 2 specimens, #WM13, 16.3.1981, 1 specimen, #WM12, 17.2.1981, 1 specimen, #WM12, 18.5.1981, 1 specimen, 3.3.1982, leg. J. Adis; 1 specimen, 3.3.1982, tree eclector, leg. J. Adis ( INPA, UIC, AMNH) .

Diagnosis:

The species closely resembles E. titschacki in colour, shape of antennae, and shape of abdominal tergite VIII of male. In E. adisi the two pronotal impressions in the midline are absent, the apical part of the central lobe of the aedeagus is placed in a more or less rectangular angle to the basal part and the paramera are also angulated, whereas they are straight in E. titschacki . Posterior edge of abdominal tergite VIII of male is slightly obtuse in E. adisi , whereas it is of more semicircular shape in E. titschacki .

Description:

Length: 1.8 – 1.9 mm. Colour: dark yellow, legs lighter yellow.

Head: 0.23 mm long, 0.33 mm wide; eyes large and distinctly prominent; temples behind eyes narrowed to the neck without rectangular angle; setiferous punctation fine, but distinct; distance between punctures as wide as diameter of punctures; a midline without or with sparser punctures; setae pointing to the midline; surface with weak and sparse microsculpture, shiny, but not polished.

Antennae with 2 nd antennomere short and globular; 3 rd antennomere conical and slightly longer than 2 nd; antennomeres 4 to 6 more or less quadrate; the following antennomeres wider than long and increasing in width except 8 th antennomere being smaller than 7 th and 9 th; 10 th antennomere 1.5 times wider than long.

Pronotum: 0.27 mm long, 0.33 mm wide; widest shortly behind anterior angle; slightly narrowed to posterior deep emargination; two long dark marginal setae and one dark seta at anterior edge; sides additionally with several dark shorter setae; setiferous punctation as on head; with irregular smooth midline; discal setae yellow pointing to midline; surface as on head with weak microsculpture and shiny, but not polished.

Elytra: 0.35 mm long, 0.40 mm wide; widest in the posterior half; distinctly narrowed to shoulders; base distinctly deeper than disc; setiferous punctation and surface as on pronotum; sides with several long dark setae.

Abdomen much finer and sparser punctate than elytra; surface less shiny; abdominal tergite VIII with few long dark setae in a more or less dense pubescence and obtuse posterior edge.

Aedeagus with thick central part and nearly rectangular apical part; paramera also angulate, but with obtuse angle with basal and slender apical segment; apical transparent plate circular; diameter of transparent plate approximately half as wide as length of apical segment of paramera.

Etymology:

The species is named in honour of my passed friend Prof. Joachim Adis, who found this species in the Central Amazon near Manaus during his studies in the Várzea of the Amazon river.

Figures

Figs 6-8: Espeson adisi (6), E. titschacki (7); E. subtilis (8); a: fore body, b: antenna, c: aedeagus, d: apex of paramera, e: abdominal tergite VIII of male (scale bar: a:, b: 0.5 mm, c–e: 0.1 mm).