Delphastus hirtulus (Kirsch) Kirsch, 2011

Shockley, Floyd W. & Vandenberg, Natalia J., 2011, Notes on the taxonomic identity of Bystus hirtulus (Kirsch) and transfer from Endomychidae to Coccinellidae (Coleoptera: Cucujoidea), with designation of a lectotype for Alexia hirtula Kirsch, Zootaxa 2868, pp. 62-68 : 64-65

Delphastus hirtulus (Kirsch) , new combination

Figs. 2–5 , 9

Alexia hirtula Kirsch, 1876: 132 . (in part)

Rhymbus hirtula (Kirsch) : Csiki, 1901: 42. (in part) Rhymbus hirtulus (Kirsch) : Csiki, 1910: 53. (in part) Bystus hirtulus (Kirsch) : Strohecker, 1953: 22. (in part)

Type material. Lectotype (here designated to ensure nomenclatural stability): “Poznzn [sic, apparent misspelling of Pozuzu, a river in Peru] Coll Kirsch [green label] / Typus [red label] / Staatl. Museum für Tierkunde, Dresden / Lectotype Alexia hirtula Kirsch, 1876 , des. F.W. Shockley & N.J. Vandenberg, 2010 [red label]” (male). Paralectotypes: 3, all with identical labels, “Pozuzu Coll. Kirsch [green labels] / Staatl. Museum für Tierkunde, Dresden / Paralectotype Alexia hirtula Kirsch, 1876 [yellow labels].” Additional labels have been added to differentiate among the 3 paralectotypes: 1, a disarticulated, cleared specimen, returned in genitalia vial on original pin, “#1 / Delphastus hirtulus ( Kirsch), 1876 , det. F.W. Shockley & N.J. Vandenberg, 2010” (female); 1, an intact point-mounted specimen, “#2 / Microscymnus n.sp., det. F.W. Shockley & N.J. Vandenberg, 2010” (male); and 1, a partial point-mounted specimen lacking head, thorax and one elytron, “#3 / Scotocryptini (Leiodidae) , probably Aglyptinus sp., det. F.W. Shockley & N.J. Vandenberg, 2010” (sex not determined) ( SMTD).

Diagnosis. Delphastus hirtulus can be distinguished from its congeners by the combination of a short clypeus ( Fig. 2 ) and distinctly punctate elytra bearing long erect hairlike setae sparsely distributed over the dorsal surfaces ( Fig. 9 ), and the presence of a dense patch of short, decumbent setae on the lateral margin of the elytra beginning just above the epipleural fovea for reception of the metafemoral apex ( Fig. 4 ). Delphastus anthracinus Gordon resembles this species in dorsal color pattern, vestiture, and general body form, but can be easily distinguished by the elongate clypeus which lends a nearly triangular shape to the head ( Fig. 1 ). Delphastus hirtulus can be distinguished from other “micrococcinellidae” of the New World by the traits mentioned above together with the generic characteristics of an expanded prosternum concealing the mouthparts, angulate tibiae, trimerous tarsi, and antennal club composed of a single elongate segment.

Redescription. Lectotype (male). Length 1.5 mm, width 1.0 mm. Form ovoid, slightly elongate, broadest in basal half, tapered posteriorly ( Figs. 3–5 ). Color on dorsal surfaces deep reddish brown, nearly black, paler reddish brown near anterior and lateral margins of pronotum; head orange-brown; venter dark reddish brown except lighter brown on abdominal ventrites II–V, especially near external margins; appendages yellow brown. Dorsal surfaces polished, shiny, distinctly punctate, with sparse pubescence consisting of long erect to suberect yellowish hairlike setae; dense patch of shorter decumbent hairlike setae near lateral margin of elytron in apical 2/3. Head ( Fig. 2 ) transverse, oval, tapered toward clypeus, evenly convex in lateral view ( Fig. 4 ), weakly opisthognathous in repose, with intermixed fine and coarse punctures mostly concentrated in band between eyes ( Fig. 2 ), with few decumbent hairs present (specimen apparently abraded); clypeus short, shallowly arcuate, projecting beyond ventral cusp of emargination for antennal insertions by about 1/4 distance separating ventral cusps. Pronotum with unevenly scattered, intermixed fine and coarse punctures; punctures separated by less than one to several puncture diameters; with scattered decumbent to erect hairlike setae. Elytron with disc evenly punctate; punctures fine, separated by 3– 5 times their diameter; some punctures bearing long, erect, hairlike seta ¾ or more length of lateral pronotal margin, estimated number of setae 65, of which only about a dozen remain due to abrasion (see setal map Fig 9 and description based on paralectotype, below), remaining punctures each bearing microseta scarcely projecting beyond rim of puncture; dense elongate pubescent patch of more than 20 short decumbent setae near lateral margin beginning just above epipleural fovea for reception of metafemoral apex, continued posteriorly to area above hind margin of 4th abdominal ventrite ( Fig. 4 ); lateral margin of elytron slightly undulate, with weakly raised lateral bead; epipleuron with depression for reception of mid-, hind femora. Prosternum convex with anterior margin arcuate, with few very fine scattered punctures. Meso-, metasternum obscured by glue and paper point. Abdomen with intercoxal process of ventrite I with few fine scattered punctures; ventrites II–IV finely rugostriate; ventrite V with narrow rugostriate band near base, remainder polished with moderately coarse scattered setiferous punctures separated by 3–5 times their diameter; each seta about ¼ to 1/3 length of segment along midline. Meso-, metatibiae with median cusplike angulation on outer margin of ventral face.

Paralectotype #1 (female). Similar to male except head, pronotum entirely dark reddish brown, nearly black. Dissection and clearing provided the following information not observable in the point-mounted, undissected lectotype. Elytron with approximately 65 punctures each bearing long erect hairlike seta ¾ or more length of lateral pronotal margin (count based on scattered remaining setae and setal bases of broken setae, Fig. 9 ), forming about 7 striae: 4 uniseriate discal striae, 2–3 somewhat confused marginal/submarginal striae; lateral patch of short decumbent setae not seen (apparently abraded). Mesosternum with shallow intermediate-sized punctures. Metasternum with coarse to intermediate-sized punctures separated by less than to 5 times their diameter; punctures more deeply impressed in median half of sclerite, nearly obsolete laterally. Details of female genitalia not clearly observed in dissection.

Original Latin description ( Kirsch 1876): “Subhemisphaerica, nigra, capite prothoracisque lateribus saepe rufescentibus, hujus angulis posticis subrectis, scutello triangulari; elytris levissime parce punctatis, pilis longis erectis sparse obsitis pedibus flavis. Long. 1½, lat. 1 Mill.” (English translation: Subhemispherical, black; head and prothorax with sides often reddish, its [the prothorax’] hind angles nearly straight [=right angled]; scutellum triangular, elytra very sparsely punctate, everywhere sparsely covered with long erect hairs; legs yellow. Length 1 ½, width 1 mm.)

Figures

FIGURE 9. Delphastus hirtulus, setal map of elytra based on dissected cleared paralectotype # 1. Dorsolateral view of left and right elytra.

FIGURES 1 – 2. Heads of Delphastus species (diagrammatic view with setae omitted and head tilted so that line of sight is perpendicular to tangent plane at center of capsule). 1, D. anthracinus, male. 2, D. hirtulus, male.

FIGURES 3 – 8. Digital images of A. hirtula type series. 3 – 5, Lectotype, male, whole body. 3, Frontal view (many setae abraded). 4, Left lateral view (note submarginal patch of decumbent setae in apical half). 5, Dorsal view (many setae abraded). 6 – 8, Paralectotype # 2 (= Microscymnus, undescribed species). 6, Frontal view. 7, Dorsal view, detail showing impressed parasutural striae forming parenthetical grooves. 8, Dorsal view of whole body.