Symmela paschoali Pacheco, Wipfler, Monné and Ahrens, 2022

Pacheco, Thaynara L., Wipfler, Benedict, Monné, Marcela L. & Ahrens, Dirk, 2022, The genus Symmela Erichson, 1835 (Coleoptera, Scarabaeidae, Sericini): taxonomy and phylogenetic analysis, Journal of Natural History 56 (9 - 12), pp. 607-705 : 677-679

Symmela paschoali Pacheco, Wipfler, Monné and Ahrens sp. nov.

( Figures 23 , 29 (d), 31(g))

Type material examined

Holotype. ♂ ‘ Asuncion Paraguay Acc. No. 2966/ L.W. Saylor Collection / Det. L.W. Saylor / CASENT 8438099/ 150 Neotropical Sericini spec.’ ( CAS) . Paratypes: 1 ♂ ‘ Taperina Brazil Acc . No. 2966/ L.W. Saylor Collection/ CASENT 8438100’ ( ZFMK), 1 ♂ ‘ Santarem June 1919 . S.M. Klages. Acc. 6324/ L.W. Saylor Collection/ CASENT 8438101’ ( CAS).

Description

Length: 6.4 mm. Elytral length: 3.9 mm. Width: 3.4 mm. Head black, dull and shiny, with erect, sparse setae. Labroclypeus as wide as frons, subtrapezoidal; surface flat; plain, without an anterior concavity on each side; anterior margin weakly emarginated medially, not elevated, with a rim of dense, short setae behind anterior margin; lateral margin not incised anteriorly; punctation of surface posteriorly dense; suture between labrum and clypeus invisible. Smooth area in front of eye distinctly separated from frons by a suture. Frons anteriorly flat, punctation irregular, dense. Ocular canthus without terminal setae, ratio of length of ocular canthus/eye diameter: 1/3. Eyes evenly spherical, ratio of diameter/interocular width: 0.5. Antenna with eight antennomeres. Antennal club with three antennomeres, blackish, straight; width of antennal lamella equal to width of antennomeres of funiculus; apical lamella subequal to basal and median ones; length ratio of third vs fourth antennomere: 1/2; fourth antennomere without lateral projection; length ratio of fifth vs fourth antennomere: 1/3. Labrum anteriorly bluntly angled on each side, concave at middle. Setae on mentum moderately dense.

Head and pronotum without copper iridescent shine. Pronotum bicoloured, dull, blackish brown; widest before base, width subequal to width of elytral base at humerus; anterior marginal line not interrupted medially, posterior marginal line absent; lateral margin not serrated, generally weakly convex, behind anterior angles convex, posteriorly weakly convex; setae of lateral margin sparse; basal margin evenly curved; transverse impression beside basal margin absent; anterior angles produced, sharply pointed; antero-lateral and postero-lateral angles not flattened dorso-ventrally; posterior angles blunt; surface without median longitudinal impression, transversal furrows or setae; punctation on disc dense, simple and fine, without well-defined impunctate areas. Scutellum without punctures.

Elytra unicoloured, blackish brown; surface opaque and iridescent, without setae and microsculpture; striae and intervals distinct; punctation between striae sparse, diameter of punctures compared to those of striae smaller; intervals flat; posterior edge convex; apical margin chitinous, without microtrichomes.

Abdomen: sternites flat in sagittal plane; lateral carina absent; first visible ventrite with row of setae on posterior edge; second visible ventrite with row of setae in medial region; basal ventrites medially of same length as laterally; ultimate and penultimate apical ventrites simple and flat; apical ventrite short (as long as preceding ventrite); penultimate apical ventrite row of setae denser and with longer setae, at middle interrupted by a flat impunctate discoid area; beside row of setae, almost glabrous. Pygidium strongly convex.

Legs reddish brown and yellow. Ratio of length of metepisternum/metacoxa: 1/1.38. Metacoxa entirely plain, without elevated lateral longitudinal carina; without longer lateral bristles, with setae on basal surface, posterior margin glabrous. Metafemur with posterior margin straight. Metatibia widest at apex; ratio of width/length: 1/3.10; dorsal margin not carinated, smooth; interior surface more or less glabrous; median longitudinal punctation present on interior surface; interior margin of apex sharply and deeply truncate towards ventral margin; punctation on entire lateral face present; beside dorsal margin without a row of robust setae along entire length; basal group of spines comprising at least two robust spines at same level of metatibial length; distal groups of spines disposed at two-thirds of metatibia length; ventral margin not serrated. Dorsal surface of tarsi glabrous, with dense punctures. Length ratio of dorsal tibial spur/first metatarsomere: 1/2. Metatarsi at apex weakly widened; first tarsomere straight, its length subequal to second and third tarsomeres combined; laterally not carinate; ventral margin serrated; ventral margin glabrous; medial face glabrous. Protibia with two distinct teeth; spur straight. First protarsomere straight, its length subequal to second and third combined; width ratio of first protarsomere vs second protarsomere: 1.5/1; second protarsomere enlarged; third and fourth protarsomere elongate and narrow (distinctly longer than wide); fifth protarsomere circular in cross section, a little shorter than third and fourth protarsomere combined. Protarsal claws asymmetrical, shape of inner protarsal claw bifid, apex of basal tooth of inner protarsal claw convex.

Aedeagus: Figure 23 (c–e).

Female unknown.

Variation

Length: 6.4–6.9 mm. Elytral length: 3.8–3.9 mm. Width: 3.3–3.4 mm. Body colour rather variable, from entirely yellowish to dark reddish brown.

Diagnosis

Symmela paschoali sp. nov. is in external and genital morphology similar to S. brasiliensis . However, the new species is much darker, the first protarsomere more strongly enlarged, and the parameres of S. paschoali are distinctly longer.

Etymology

This species is named after Paschoal C. Grossi, a Brazillian entomologist who has been making great contributions on Neotropical scarab taxonomy (noun in genitive case).

Remarks

This species does not present a common distribution, with two very disjunctive records ( Figure 29 (d)). This fact leads us to suspect that (1) the species has a wide distribution with large sampling gaps, or (2) there is an error in the locality labels of at least one specimen.

Figures

Figure 23. Symmela paschoali sp. nov., holotype ♂. (a) Habitus, lateral view; (b) habitus, dorsal view; (c) parameres, dorsal view; (d) aedeagus, dorsal view; (e) aedeagus, lateral view. Scale bars: a, b = 1 mm; c–e = 0.5 mm.

Figure 29. Distribution map of the Symmela species.