Perumicrus peruanus (Franz) Franz, 2015

Jałoszyński, Paweł, 2015, Revision of Neotropical species of ant-like stone beetles misplaced in Stenichnus and Scydmoraphes (Coleoptera, Staphylinidae, Scydmaeninae), Zootaxa 4027 (2), pp. 253-269 : 268

Perumicrus peruanus (Franz) comb. nov.

( Figs 11 , 21–24 , 27 , 30 )

Scydmoraphes peruanus Franz, 1980a: 210 , fig. 198.

Material studied. Remnants of holotype ( PERU) ♂: three labels ( Fig. 30 ): "Umg. Tarapoto / Peru,lg.Franz" with "SA 133" on the reverse side [white, printed; reverse handwritten], " Scydmoraphes / peruanus m. / det.H.Franz" [white, handwritten and printed], " Typus " [red, handwritten] ( NHMW). A white printed label was added during the present study: " PERUMICRUS / peruanus / (Franz, 1980) / det. P. JAŁOSZYŃSKI, '2015". Remnants of paratypes: 2 ♂♂, same data as holotype, except yellow identification " PARATYPUS " label ( NHMW). See Remarks below for details on the state of preservation.

Diagnosis. This is the only known species of Perumicrus and can be identified on the basis of the generic characters and the aedeagus.

Description. Body of male (not shown due to incomplete and disarticulated specimens) slightly flattened, elongate and slender, with moderately long appendages, BL 0.59 mm; moderately glossy, uniformly brown with slightly lighter appendages; vestiture slightly lighter than cuticle.

Head ( Figs 21–22 ) short and subtrapezoidal in shape, broadest at eyes, HL 0.10 mm, HW 0.13 mm; occipital constriction slightly broader than frons between eyes; 'neck' region much broader than long; tempora much shorter than eyes, lacking lateral bristles; vertex short and broad, anteriorly confluent with frons, convex; frons subtrapezoidal, weakly convex, with anterior margin slightly projecting anteriorly at middle; supraantennal tubercles feebly marked; eyes very large and strongly projecting laterally. Vertex and frons with distinct punctures separated by spaces subequal to their diameters; setae short, sparse and suberect. Antennae ( Fig. 21 ) short in relation to body length, AnL 0.20 mm; antennomeres I–II strongly elongate, III–V nearly as broad as long, VI–X each transverse, XI narrower than X, about as long as broad, with rounded apex.

Pronotum in dorsal view subquadrate with rounded sides, broadest near anterior third, PL 0.14–0.15 mm, PW 0.15–0.18 mm; anterior margin nearly straight; sides strongly rounded in anterior half and distinctly convergent caudad, posterior margin shallowly bisinuate; base with distinct transverse groove and lateral pair of elongate impressions close to each lateral pronotal margin. Pronotal disc with fine and inconspicuous punctures; setae short, sparse and suberect, bristles absent.

Elytra studied only in transparent mount and disarticulated; oval, broadest presumably near or slightly anterior to middle, EL 0.35 mm, covered with short, sparse and presumably weakly suberect setae. Hind wings welldeveloped, about twice as long as elytra.

Legs moderately long and slender; unmodified.

Aedeagus ( Figs 11 , 27 ) elongate, AeL 0.10 mm, median lobe symmetrical, drop-shaped with subtriangular apical part; endophallic structures symmetrical, with several paired elongate sclerites; parameres slender, each with one apical seta.

Female. Unknown.

Distribution. Northern Peru, east to the Andes.

Remarks. In the original description Franz (1980a) gives further collecting data: Juan Guerra, south of Tarapoto, relatively dry forest, leaf litter, 28.09.1968.

Specimens in the type series are poorly preserved and none is complete. Only disarticulated elytra, one leg and aedeagus of the holotype have survived (elytra and leg mounted in Canada balsam, aedeagus in original Franz's preparation in euparal). One paratype male was originally disarticulated and embedded in euparal; during the present study it was remounted in Canada balsam. This specimen is almost complete, lacking only the elytra. The other paratype male was also disarticulated and dry-mounted, with the aedeagus in euparal; it also lacks the elytra.

Figures

FIGURES 9 – 11. Meridaphes venezolanus (Franz) (9, 10) and Perumicrus peruanus (Franz) (11). Dorsal habitus of male holotype (9) and aedeagus in ventral view (10, 11).

FIGURES 21 – 24. Morphological structures of Perumicrus peruanus (Franz), paratype male. Head in dorsal (21) and ventral (22) views; prothorax in ventral view (23); pterothorax in ventral view (24). Abbreviations: ar, anterior ridge of mesoventrite; bst, basisternal part of prosternum; bst, basistipes; cd, cardo; fr, frons; gal, galea; gp, gular plate; gs, gular suture; h, hypomeron; hy, hypostomal ridge; hyr, hypomeral ridge; lac, lacinia; lb, labrum; lp, labial palp; lmfa, lateral metafurcal arm; mcp, mesocoxal projection; md, mandible; mn, mentum; mscc, mesocoxal cavity; mscs, mesocoxal socket; msff, mesofurcal fovea; mst, mediostipes; msvp, mesoventral intercoxal process; mtvp, metaventral intercoxal process; mxp, maxillary palp; nr, ' neck' region; occ, occipital constriction; pf, profurca; pre, prepectus; pcc, procoxal cavity; pcs, procoxal socket; ptp, posterior tentorial pits; smn, submentum; v 3, metaventrite; vlf, ventrolateral fovea; vt, vertex.

FIGURES 25 – 27. Meridaphes venezolanus (Franz) (25, 26) and Perumicrus peruanus (Franz) (27). Aedeagus in ventral (25, 27) and lateral (26) views.

FIGURES 28 – 30. Original set of labels of holotypes. Sciacharis andicola (Franz) (28), Meridaphes venezolanus (Franz) (29), and Perumicrus peruanus (Franz) (30).