Parosus minutus, Makranczy & H-, 2014

Makranczy, György, 2014, Review of the genus Parosus Sharp, 1887 (Coleoptera: Staphylinidae, Oxytelinae), Revue suisse de Zoologie 121 (1), pp. 77-133 : 114-116

Parosus minutus sp. nov. Figs 95, 101-103, 135

TYPE MATERIAL: HOLOTYPE (3), “ PANAMA, [Prov.] Panama, Cerro Azul [9°10'01"N, 79°24'54"W], ca. 2000’, Feb. 21.1976, [leg.] A. Newton, wet debris, small forest stream” ( FMNH). – PARATYPE (1), PANAMA: Prov. Panama, Cerro Campana, 3200’ [8°41'15"N, 79°55'19"W], 14-23.II.1976, leg. A. Newton, berlese - cloud forest leaf litter ( FMNH, 1) .

DESCRIPTION: Habitus as in Fig. 135. Measurements (n=2): HW = 0.41 (0.39- 0.42); TW = 0.39 (0.38-0.40); PW = 0.38 (0.37-0.39); SW = 0.39 (0.38-0.39); MW = 0.47 (0.46-0.47); AW = 0.41 (0.39-0.43); HL = 0.31 (0.30-0.31); EL = 0.10 (0.10-0.10); FL = 0.09 (0.08-0.09); TL = 0.11 (0.10-0.12); PL = 0.29 (0.28-0.29); SL = 0.45 (0.43- 0.47); SC = 0.44 (0.41-0.46); FB = 1.08 (1.05-1.11); BL = 2.06 (2.00-2.12) mm. Body predominantly 'unicoloured', but with light elytra. Head blackish dark brown FIGS 107-114

(107-110) Parosusportobelo sp. n.; head (107), pronotum (108), elytron (109), sideofhead (110). (111-114) P. rossii sp. n.; head (111), pronotum (112), elytron (113), sideofhead (114). All SEM, dorsal views. Scale bar = 0.16 mm for 110, 0.2 mm for 114, 0.25 mm for 107-109, 0.35 mmfor 111-113.

(supraantennal prominences appear much lighter, yellowish), pronotum dark brown, elytra light brown except scutellar area to shoulders darker (poorly delimited). Abdomen dark brown (with the posterior margin of tergites somewhat lighter). Legs, mouthparts and antennae yellow to light brown with the middle darkened (medium brown) until the penultimate antennomere. Pubescence rather short and relatively sparse (this being by far the smallest species), with longer setae on the abdomen. Rather shiny species, punctured areas not separating sharply.

Head and pronotum. Mid-antennal articles about as long as wide (antennomere 6 length:width = 0.046: 0.045 mm). Clypeus (Fig. 101) broad trapezoid, ratio of longitudinal distance of supraantennal prominence tip from eyefront to the same from clypeal front = 0.50-0.64. Infraocular ridge (Fig. 103) fine, ending in a very short keel at posterior edge of eye. Temple almost evenly curved, but most curved in the middle. Pronotum (Fig. 101) with maximum width 1.58-1.66x base width, sides convex, curved all the way, but most in anterior third, anterior angles rather sharp. Clypeus and supraantennal ridges almost unpunctured, shiny. Clypeal area poorly delimited, frontoclypeal groove almost absent, marked only as a border between unpunctured and punctured areas. Vertex not visibly impressed, but in middle a spot more sparsely punctured, shiny and a little elevated. Posterior part of pronotal midline an elevated and shiny stripe. Around it disc slightly depressed, especially at anterior part of midline which stands out as unpunctured. Pronotal sides with impressions around the middle. Head with 16-20 'longitudinal' puncture lines, pronotum with 16-18 'longitudinal' puncture lines, anterior vertex more loosely punctured.

Elytra and abdomen. Elytra (Fig. 102) dilating posteriorly, with two small, longitudinal, rather deep impressions behind scutellum. Medially serrate fringe present on hind margin of tergite VII. Head, pronotum and elytra with similarly sized punctures, but elytral punctation not umbilicate, interspaces about 1/3-2/3 of puncture diameters. Bases of tergites (posterior to basal ridges) (also) without microsculpture, segments with tiny, scattered punctures. Aedeagus as in Fig. 95.

ETYMOLOGY: The specific epithet refers to this taxon being by far the smallest species.

COMPARATIVE NOTES: Easy to distinguish from all other known Parosus by its small size alone.

DISTRIBUTION: The species is known only from a pair of specimens collected in Panama (Prov. Panama) at different localities. These being the only ones in their repectives samples suggest rarity.

BIONOMICS: Collected from wet debris near a small forest stream, also by

Berlese sampling of leaflitter in a cloud forest.