Heteroscydmus brasiliensis (Franz) Franz, 2017

Jałoszyński, Paweł, 2017, Confused identity: Pseudoeudesis brasiliensis Franz transferred to Heteroscydmus Franz, and Pseudoeudesis castrii Franz placed in Anthicimimus Franz (Coleoptera: Staphylinidae: Scydmaeninae), Zootaxa 4250 (4), pp. 378-388 : 381-383

Heteroscydmus brasiliensis (Franz) , comb. n.

( Figs 1–2 , 4–8 )

Pseudoeudesis brasiliensis Franz, 1967: 668 .

Type material studied. Lectotype (here designated) ( BRAZIL): ♀: three labels ( Fig. 8 ): " Tropenwald b. Muriqui / südl. Rio de Janeiro / Brasilien,lgt. H.Franz " [white, printed], " Pseudoeudesis / brasiliensis / m. / det. H.Franz " [yellowish, handwritten and printed], " Typus " [red, handwritten] ( NHMW) . Paralectotypes: 4 ♀♀ (one drymounted, three mounted in euparal, including two on one plastic plate), same data as for lectotype ( NHMW) .

Revised diagnosis. BL of female <0.6 mm; EI> 1.5; pronotum about as long as broad, with four indistinct antebasal pits and transverse impression.

Redescription. Body of female ( Fig. 1 ) elongate and slender, flattened, BL 0.50–0.55 mm; pigmentation yellowish brown; vestiture of setae slightly lighter than cuticle.

Head ( Figs 1 , 4 ) in dorsal view subtrapezoidal, broadest at eyes, HL 0.10–0.11 mm, HW 0.13 mm; tempora nearly twice as long as eyes, weakly convergent posteriorly; vertex and frons confluent and convex, anterior margin of frons slightly projected anteriorly and rounded; supraantennal tubercles feebly marked; eyes small, not projecting laterally from the silhouette of the head. Vertex and frons with inconspicuous fine punctures and sparse, short, suberect setae. Antennae ( Figs 1–2 ) relatively short, AnL 0.20 mm; antennomeres I and II distinctly elongate, III–X each strongly transverse, XI slightly shorter than IX and X combined, about as long as broad, subconical and blunt at apex.

Pronotum ( Figs 1 , 4 ) broadest near anterior third, strongly narrowing anteriorly and posteriorly, PL 0.13–0.14 mm, PW 0.13–0.14 mm; anterior and posterior margins arcuate; sides strongly rounded in anterior half and slightly sinuate posteriorly; base with indistinct, diffuse transverse groove connecting one pair of shallow and similarly diffuse lateral pits, additionally one smaller but more distinct pit is located laterally and slightly anteriorly to inner pair of pits. Pronotal disc with punctures and setae similar to those on frons and vertex.

Elytra ( Fig. 1 ) oval, broadest between middle and anterior third; EL 0.28–0.30 mm, EW 0.18 mm, EI 1.57– 1.71; basal impressions shallow, humeral calli distinct, elongate. Punctures and setae similar to those on pronotal disc. Hind wings well developed.

Legs ( Figs 1–2 ) unmodified, with gradually clavate femora and short, robust tarsi.

Spermatheca ( Fig. 7 ) globular, slightly elongate, relatively thin-walled, length 0.025 mm.

Male. Unknown.

Distribution. Southeastern Brazil.

Remarks. The type specimens of H. brasiliensis are females; they clearly differ from the female of H. yapacariensis in much smaller body (BL 0.50̄ 0.55 mm vs. 0.73 mm), a shorter pronotum (the pronotum in H. yapacariensis is distinctly elongate) with a different shape of lateral margins, presence of antebasal pronotal pits (only transverse groove in H. yapacariensis ), the head and pronotum much broader in relation to the elytra, and shorter elytra in relation to their length.

Lectotype designation. Franz (1967) studied five female specimens. One of them is labeled "Typus" ( Fig. 8 ), but Franz (1967) in the original description did not select any specimen to serve as a name-bearing type (he did not use the term "holotype" or any acceptable equivalent), and the five type specimens should be treated as syntypes. The female labeled as "Typus" ( Figs 1 , 8 ) is here designated lectotype.

Another specimen most likely belonging to H. brasiliensis was found in NHMW labeled as a paratype of Pseudoeudesis sulcata Franz, 1967 (currently in Afroeudesis (Jałoszyński 2016)) . Both species were collected during the same expedition and the specimen locality labels do not differ; a mislabeling rather than misidentification was suspected by Jałoszyński (2016). This hypothesis was based on the number of specimens― Franz (1967) stated that the type series of Pseudoeudesis brasiliensis was composed of five specimens, but only four seemed to be present in NHMW. Therefore, the missing paratype of P. brasiliensis might have been erroneously labeled by Franz as P. sulcata and placed in a drawer under this name. However, this hypothesis was proved wrong during the present study; among the four specimens of P. brasiliensis one turned out to be composed of two beetles embedded in euparal on one plastic rectangle. Therefore, the number of correctly labeled type specimens of P. brasiliensis in the Franz Collection agrees with that given in the original description, but the one mislabeled as P. sulcata is a surplus specimen and almost certainly not a paratype.

Figures

FIGURES 1 – 3. Species of Heteroscydmus Franz. Heteroscydmus brasiliensis (Franz), comb. n., (1, 2); Heteroscydmus yapacariensis Franz (3).

FIGURES 4 – 5. Heteroscydmus brasiliensis (Franz), comb. n., lectotype female. Head and prothorax in dorsal (4) and ventral (5) views. Abbreviations: abg, antebasal groove; abp, antebasal pit; bst, basisternal part of prosternum; fr, frons; gp, gular plate; hr, hypostomal ridge; hyr, hypomeral ridge; mn, mentum; mxp, maxillary palp; nss, notosternal suture; occ, occipital constrictions; psp, prosternal process; ptp, posterior tentorial pit; smn, submentum; vt, vertex.

FIGURES 6 – 8. Heteroscydmus brasiliensis (Franz), comb. n., lectotype female. Pterothorax in ventral view (6); abdomen and spermatheca (7); original set of labels (8). Abbreviations: ar, anterior ridge; msvp, mesoventral intercoxal process; mtvp, metaventral intercoxal process; pcr, procoxal rest; pre, prepectus; sp, spermatheca; v 3, metaventrite.