Glyptoma guianense, Irmler, 2015

Irmler, Ulrich, 2015, The neotropical genus Glyptoma ERICHSON, 1839 with descriptions of new species and a key to the species (Coleoptera: Staphylinidae: Osoriinae), Beiträge Zur Entomologie = Contributions to Entomology 65 (2), pp. 297-325 : 309

Glyptoma guianense spec. nov.

( Figs 9A, B , 21C )

Type material: male, Holotype: Guyana: Region 8, Iwokrama Forest, 26 km SW Kurupukari, Iwokrama Mt. base camp (58°48.38'W, 4°20.17'N), under bark, 60 m elev. 24.5.2001, leg. R. Brooks & Z. Falin, # GUY1BF01019 ( KNHM). Paratypes: 1 female, 1 male, with same data as holotype; 1 female, same region, Kabocalli Field Stn. (58°30.35'W, 4°17.4'N), under bark, 60 m elev., 5.6.2001, leg. R. Brooks & Z. Falin, #GUY1BF01140 ( KNHM, UIC) .

Diagnosis: Glyptoma guianense seems to be the sister species of G. amazonense spec. nov. regarding the very similar aedeagus and microsculpture. It differs in the less deep pseudo-punctures on head and pronotum. Furthermore, the temples of G. amazonense are more angulated, nearly rectangular, whereas they are convex in G. guiananense . Regarding the aedeagus, sensillae of the apical lobe of G. guianense are concentrated close to the apex, whereas in G. amazonense they are concentrated at the middle of the apical lobe.

Description: Length: 2.6–2.7 mm. Colouration: Black; legs and antennae dark brown; tarsi lighter brown.

Head: 0.39 mm long, 0.48 mm wide; eyes prominent; slightly shorter than temples; temples narrowed in smooth convex curve to neck; sides in front of eyes parallel up to base of antennae; parallel part nearly twice as long as eyes; narrowed anterior angle of clypeus in rectangular angles; anterior edge of clypeus one fourth as wide as distance between base of antennae; setiferous punctures large; on average, interstices between pseudo-punctures less than half as wide as diameter of punctures; setiferous punctures on ridges between pseudo-punctures; yellow setae as long as or longer than diameter of pseudo-punctures; clypeus without pseudo-punctures and setiferous punctures; isodiametric microsculpture deep and dense; on surface of pseudo-punctures and on ridges; setiferous punctures nearly invisible within deep microsculpture; surface totally matt.

Antennae slightly longer than head and pronotum combined; second antennomere slightly narrower than first; nearly twice as wide as long; following antennomeres as wide as first; third to eighth antennomere approximately 1.5 times as wide as long, ninth and tenth antennomere twice as wide as long; second to tenth antennomere with long yellow setae; penultimate antennomeres with denser setation than basal antennomeres; setae slightly longer than width of antennomeres.

Pronotum: 0.40 mm long, 0.45 mm wide; widest at middle; in anterior half, narrowed to anterior angles in smooth convex curve; anterior angles widely rounded; in posterior half, narrowed to posterior angles in concave curve; posterior angles shortly rounded; pseudo-punctures as large and dense as on head; on average, ridges between pseudo-punctures less than half as wide as diameter of pseudo-punctures; setiferous punctures inserting on ridges; yellow setae approximately as long as diameter of pseudo-punctures; at posterior angles with deep groove similar to pseudo-punctures, but more elongate, isodiametric microsculpture as deep and dense as on head; total surface matt.

Elytra: 0.59 mm long, 0.59 mm wide; sides smoothly rounded, but nearly parallel; shoulders distinct; nearly rectangular; anterior edge emarginate; discal carina distinct; lateral carina irregular and indistinct; suture line impressed; formed by small densely coriaceous punctures; continued to posterior margin; between suture line and discal carina several extremely large pseudo-punctures; partly coriaceous; interstices between pseudo-punctures restricted to small ridges; setiferous punctures on ridges; laterally to discal carina with more irregular and dense pseudo-punctures and setiferous punctation; microsculpture as dense and deep as on head and pronotum; on surface of pseudo-punctures more isodiametric, on surface of ridges more elongate; total surface matt.

Abdomen with one transverse row of pseudo-punctures; setiferous punctures restricted to small ridges between pseudo-punctures; posterior segments with denser setiferous punctation than anterior segments; isodiametric microsculpture as dense and deep as on fore-body; surface matt;

Aedeagus with obtuse angle between basal and apical lobe, apical lobe wider at middle than at base; close to apex sinuate; ending in acute apex; lateral sensillae densest at apex; sparser closely behind; paramere short; ending approximately at end of basal third of apical lobe.

Etymology: The species name derived from the country, where it was collected.

Figures

Figs 21: Fore body of Glyptoma crassicorne (A), G. lescheni (B), G. guianense (C), G. amazonense (D), G. guadelupense (E), G. hirticorne (F); scale bar 0.5 mm.

Figs 7–12: Aedeagus (A) and antenna (B) of Glyptoma crassicorne (7), G. lescheni (8), G. guianense (9), G. amazonense (10), G. guadelupense (11), G. hirticorne (12); scale bar: 0.1 mm.