Eleusis fauveli, Irmler, 2017

Irmler, Ulrich, 2017, The Neotropical species of the genus Eleusis LAPORTE, 1835 with description of the new genus Eleusima (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 67 (2), pp. 275-318 : 282-283

publication ID

https://doi.org/ 10.21248/contrib.entomol.67.2.275-318

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scientific name

Eleusis fauveli

spec. nov.

Eleusis fauveli spec. nov.


Figs 7 View Fig A-C, 28E,35a

Isomalus tenuis FAUVEL, 1864: 41 new synonymy

Type material examined: male, Lectotype: Venezuela: Caracas ( IRSNB). A male and a female specimen are deposited in IRSNB with same the label “Caracas”. The male specimen is labelled “tenuis” by Fauvel. I selected the male specimen as Lectotype .

Additional material examined: Costa Rica: Heredia, La Selva, Biol. Station nr. Puerto Viejo de Sarapiqui , male, 18.2.1985, leg. L. Herman ( AMNH) ; 3 km S Puerto Viejo , OTS La Selva, 100 m, male, Sept. 1992, leg. P. Hanson ( KNHM) ; same location and same collector, but female, Malaise trap, Dec. 1992 ( KNHM) ; San Isidro de General , 700-800 melevation, Aug.1980, leg. L.H. Kraus ( AMNH) ; Panama: Colon, Parque Soberania, Pipeline Rd. (9°07'N, 79°45'W), flight intercept trap, female, 18.- 19.5.1995, J. Jolly & C. Chaboo ( AMNH) GoogleMaps ; Venezuela: Bolivar, between Sta. Elena de Uairen and Icabarú , 30.7.1987, leg. M.A. Ivie ( KNHM) ; Suriname: Commewijne, Akintosoela , CELOS Camp, 39 km Se Suriname River bridge, road to Redi Doti (5°16.17'N, 54°55.15'W), 40 m elevation, under bark, female, 30.6.1999, leg. Z. Falin #SUR1F99 129 ( KNHM) GoogleMaps ; Sarmacca , West Suriname Road , 108 km WSW Zanderij Airport (5°13.37'N, 55°52.54'W), 30 m elev., under bark, 5 females, 9.7.1999, leg. Z. Falin, #SUR1F99 048 (4 KNHM, 1 UIC) GoogleMaps ; French Guiana: nr. Eaux Claires , 3.5 mi N Saül (3°38-40'N, 53°13- 14'W), 155-260 m elev., under bark, 3 males, 2 females, 5.- 13.10.1995, leg L. Hermann, #2804 (4 AMNH, 1 UIC) ; Trinidad: Arimaq Valley , 800-1200 ft elev., female, 10.- 22.2.1964, leg. Rozen & Wygodzinsky ( AMNH) ; nr. Eaux Claires , 3.5 mi N Saül (53°13-14'W, 3°38-40'N), 155-260 m elevation, under bark of log, 2 females, 5.- 13.10.1995, leg. L. Herman #2836 ( AMNH) ; Trinidad: Arima Valley , 800-1200 ft. 10.- 22.2.1964, Rozen & Wygodzinsky ( AMNH) ; Peru: Tambopata, Prov., Madre de Dios Dept. , 15 km NE Puerto Maldonado, Reserva Cuzco Amazónica (12°33'S, 69°03'W), 200 m elev., swamp trail, flight intercept trap, male, 17.7.1998, leg. J.S. Ashe & R.A. Leschen #485 ( KNHM) GoogleMaps ; same location, but under bark with fermenting sap, female, 3.7.1989, leg. J.S. Ashe & R. Leschen ( KNHM) GoogleMaps Brazil: Santa Rita , female, Aug. 1850 ( BMNH) ; Amazonas, Rio Purus , female, 24.9.1874, leg. Trail ( BMNH) ; Såo Paulo de Olivença ( BMNH) ; Paraná, Rondon , female, 24.9.1952, leg. F. Plaumann ( BMNH) .

Diagnosis: The species was described as Isomalus tenuis by FAUVEL (1864), a name which was preoccupied by E. tenuis WALKER, 1859 . It was later synonymised with E. humilis ERICHSON, 1840 . It is, however, a distinct species, but extremely similar to E. humilis . It is significantly smaller than E. humilis and the central prominence of the aedeagus is still weaker and shorter. Moreover, E. tenuis is brown and the posterior margin of the elytra is only slightly darker, whereas in E. humilis the head and the posterior margin of the elytra are black.

Description: Length: 2.2 – 2.4 mm; Colouration: light brown, head darker brown, pronotum slightly lighter brown, elytra light brown, partly transparent; posterior margin of elytra slightly darker; legs and antennae yellow.

Head: 0.33 mm long, 0.41 mm wide; on average, slightly wider than long, without significant variance between specimens; no sexual dimorphism; temples smoothly rounded; preocular sides shortly parallel to base of antennae; anterior margin of clypeus sinuate to central prominence; supraocular groove short; weak punctation dense; on average, interstices as wide as to twice as wide as diameter of punctures; large setiferous puncture at each end of supra-ocular groove; elongate microsculpture deep; on clypeus with transverse striae; on vertex with semicircular striae; striae mirrored along midline; surface slightly shiny.

Antennae as long as head and pronotum combined; first antennomere slightly thicker and longer than following antennomeres; twice as long as second and third; following antennomeres increasing in width; fourth antennomere slightly longer than wide; tenth slightly wider than long; antennomere four to eleven pubescent and with few apical setae.

Pronotum: 0.26 mm long, 0.30 mm wide; widest close to anterior angles; continuously narrowed to posterior angles; anterior angles widely rounded; anterior margin sinuate; posterior margin widely rounded; punctation slightly deeper than on head, but similarly dense; close to anterior angles, two pairs of large setiferous punctures at anterior margin; in anterior half, few larger punctures with setae along lateral margin; lateral margin interrupted in posterior half; interruption marked by large setiferous puncture; elongate microsculpture similarly deep and dense as on head; striae curled close to anterior angles; on disc similarly semicircular as on head; mirrored along midline; surface slightly shiny.

Elytra: 0.49 mm long, 0.48 mm wide; widest close to posterior angles; posterior angles obtuse; punctation and microsculpture much weaker than on head and pronotum; nearly invisible; pair of setiferous punctures on central disc; one puncture on each side of suture; surface shiny.

Abdomen with transverse microsculpture; punctation as deep and dense as on fore-body; surface shiny.

Aedeagus with broad basal part of central lobe; in lateral aspect, apical half distinctly narrowed to obtuse apex; in ventral aspect, apical half approximately parallel; endophallus with two differently long spurs; prominence at midline of central lobe extremely weak; with only few sensillae; on each side of prominence several more sensillae; paramere slightly shorter than central lobe; transparent lobe slightly widened; at apical margin of transparent lobe with one thick seta; at apical margin with minute sensillae; in central and basal scape with few larger sensillae.

Etymology: The species name honours A. Fauvel, who first described it as Isomalus tenuis .


Institut Royal des Sciences Naturelles de Belgique


American Museum of Natural History


The Educational Science Museum [=Kuwait Natural History Museum?]














Eleusis fauveli

Irmler, Ulrich 2017

Isomalus tenuis

FAUVEL, A. 1864: 41