Agyrtodes atropos (Blackburn)

Seago, Ainsley E., 2009, Revision Of Agyrtodes Portevin (Coleoptera: Leiodidae), The Coleopterists Bulletin (mo 7) 63, pp. 1-73 : 39-40

publication ID	https://doi.org/ 10.1649/0010-065x-63.sp7.1
publication LSID	lsid:zoobank.org:pub:B58B2216-0CFA-41C6-8141-7024E65ECF85
persistent identifier	https://treatment.plazi.org/id/039887BA-FFC1-C06A-92DF-82E5EFD89209
treatment provided by	Carolina
scientific name	Agyrtodes atropos (Blackburn)
status

Treatment

Agyrtodes atropos (Blackburn) View in CoL

(Figs. 11, 48, 68, 88, 99)

Cholevomorpha atropos Blackburn 1903: 96 View in CoL . Holotype: female, labeled ‘‘(on card)

T. 7263 Vict./ Type H. T./ Australia Blackburn Coll. B.M. 1910- 236 /

Cholevomorpha atropos Blackb. ’’ (BMNH).

Agyrtodes atropos (Blackburn) View in CoL . Jeannel (1936: 107) [transferred to Agyrtodes View in CoL ];

Szymczakowski (1966: 15); Zwick (1979: 6).

Notes on Type Material. One specimen labeled ‘‘ Cholevomorpha atropos cotype/ Dividing Rge., V, Blackb’s Coll’’ exists in SAM; because the description is explicitly based on a single specimen with the same locality as the individual in BMNH, this second specimen has no type status .

Distribution. Australia: Victoria south to Tasmania, east to coast, northeast through southern New South Wales; abundant in Dandenong Mountains northeast of Melbourne ( Fig. 99 View Fig ). Material examined listed in Appendix 1.

Diagnosis. The following characters can be used to distinguish A. atropos from the similarly colored (but much larger) A. globosus : Male protarsus scarcely dilated. Epistomal suture present, with small stem. Dorsum dark brown with golden vestiture; elytral bases and apices often paler brown than disc. Robust antennal club with compact, broad segments: 8 and 9 distinctly transverse. Small size (2 mm long at most).

Redescription. TBL 5 1.9 mm, EW 5 1.0 mm, PNW 5 0.9 mm, HW 5 0.45 mm. (TBL variation: 1.9 mm –2.0 mm)

Small body size, oval in dorsal view (Fig. 11). Dorsum and venter medium-todark brown, elytral and pronotal discs darker brown medially. Antennal club medium to dark brown, first two segments light brown. Dorsum clothed with abundant, pale pubescence which accentuates the lighter brown coloration of the hind pronotal margin, elytral bases and elytral apices.

Head approximately one-third as wide as pronotum, conspicuously punctate. Epistomal suture present, with small stem. Clypeus broadly rectangular, transverse. Labrum broad, transverse, lightly cleft distally. Mandible stout, of typical Agyrtodes form with blunt dens, membranous prostheca, and large grinding mola. Maxilla with slender galea bearing loose apical brush of short hairs, lacinia with dense, apical spore-brush of short, heavily sclerotized teeth. Maxillary palpi slender, sparsely pubescent, apical palpomere elongate and narrower than subapical palpomere. Labial palpi with apical segment slender, elongate, tapering, evenly covered with short digitiform sensillae.

Antennae ( Fig. 48 View Figs ) stout, robust, with broad, pronounced club. Scape and pedicel enlarged, paler in color than remaining segments, conspicuously wider than segments 3–6 and subequal in width to segment 7. Segments 3–6 serially decreasing in length, 6 roughly one-third the length of 3. Segment 7 large, twice as long as 6, roughly triangular. Segment 8 small, transverse, subquadrate. Segment 9 large, slightly shorter and wider than 7; segment 10 subquadrate, barely transverse. Apical segment larger than all preceeding segments, rounded basally, tapering abruptly to blunt, rounded apex.

Pronotum transverse, extremely convex, broadest just above hind margin, disc shining, evenly covered with shallow, closely spaced punctures. Hind angles of pronotum transparent, bluntly rectangular.

Elytra convex, bulging, rounded posteriorly, with deep longitudinal impressions flanking suture. Conspicuous transverse striolation formed by irregularly arranged rows of deep, oval punctures bearing stiff setae. Epipleura smooth, with very shallow, minute punctures. Elytral apices with longitudinal impressions formed by confluence of enlarged punctures; longitudinal impressions faintly impressed at elytral bases. Large, apparently sensory pore-like structure at apex of basalmost bulge of each elytron.

Prosternum extremely short, not extending anterior or posterior to procoxae. Trochantins partially concealed. Procoxal cavities separated by low, median, longitudinal carina of prosternum. Mesosternum broad, transverse, glabrous, with shallow, whorled microsculpture. Longitudinal carina incomplete, present only at posterior midline of mesoventrite, forming anterior separation of mesocoxae. Mesepimera elongate, rectangular, extending proximally to mesocoxal cavities. Metasternum transverse, bulging, with loose array of large deep punctures each bearing a single seta.

Legs robust, femora stout, tapering distally with paired ventral flanges at apex. All tibiae with loose, apical ring of long, robust spines. Procoxae globular, projecting. Protibiae extremely short, shorter than femora, bearing two external rows of 3–4 stout spines. Male protarsi with first three segments scarcely expanded, not wider than tibial apex; first and second segments cordate and bearing tenent setae ventrally. Mesocoxae oval, convex. Mesotibiae equal in length to mesofemora, with two external rows of 4–5 spines. Male mesotarsi not expanded, without tenent setae. Metacoxae slender, transverse, triangular, tapering laterally. Metatibiae slightly longer than metafemora, with two external rows of 5–6 spines. First metatarsomere equal in length to second and third segments combined.

Male genital segment ( Fig. 68 View Figs ) short, ovate, compact, with long, robust, tongue-shaped anterior apophysis. Aedeagus ( Fig. 88 View Figs ) with median lobe very short, cylindrical basally, slowly tapering to blunt, triangular apex, no more than half as long as parameres. Inverted endophallus with fine, short spines distally, small patch of more heavily sclerotized scale-shaped teeth basally. Parameres long, distally expanded, bearing many long, sinuous setae on internal apices. Male genital segment with long, narrow anterior apophysis.

Female terminalia typical for Agyrtodes , coxites elongate, slender and connate at base, slightly expanded distally, bearing three external and one internal seta; styli short, slender, each with terminal seta slightly longer than stylus.

Natural History. Collected in wet sclerophyll, Eucalyptus , and Nothofagus forests (often in ravines), by litter-sifting, pyrethrum-fogging and berlese from fungusy rotting logs.

Notes. A very similar Agyrtodes ‘‘morph’’ has been collected by the author and others in Victoria and New South Wales. Members of this morphotype resemble A. atropos but are very slightly larger (, 2 mm long) and display markedly pale elytral bases and apices, whereas typical specimens of A. atropos are uniformly medium to dark brown. However, the shape of the male genitalia, slender male protarsi, absent epistomal suture, deep punctation of the head, and geographic distribution of this morph all suggest that these beetles are either conspecific or very closely related to A. atropos . It is conceivable that this morph could someday be described as a new species, but I do not do so at this time given that the morphological differences between the two do not seem to be of specific quality.