Symmela nunesorum Pacheco, Wipfler, Monne and Ahrens 2022, sp. nov.
Creators: name: Pacheco, Thaynara L.
name: Wipfler, Benedict
name: Monné, Marcela L.
name: Ahrens, Dirk
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Melolonthidae
Symmela
Symmela nunesorum

description: Symmela nunesorum Pacheco, Wipfler, Monné and Ahrens sp. nov.
(Figures 21, 29 (d), 31(e), 32(g))
Type material examined
Holotype. ♂ ‘ BRASIL: Goiás. Mineiros. 1999 G. Machado / 29 Neotropical Sericini spec.’ (CEMT). Paratype: 1 ♂ ‘ BRASIL: Goiás. Mineiros. 1999 G. Machado / 29 Neotropical Sericini spec.’ (ZFMK).
Description
Length: 6.8 mm. Elytral length: 4.4 mm. Width: 3.2 mm. Head black, shiny, with erect, sparse setae. Labroclypeus as wide as frons, subtrapezoidal; surface convex; plain, without an anterior concavity on each side; anterior margin straight, weakly reflexed, 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 even, dense. Ocular canthus with terminal setae, ratio of length of ocular canthus/eye diameter: 1/3. Eyes evenly spherical, ratio of diameter/interocular width: 0.44. Antenna with eight antennomeres. Antennal club with three antennomeres, blackish, straight; width of antennal lamella equal to width of antennomeres of funiculus; apical lamella distinctly shorter than basal one; length ratio of antennal club vs remaining antennomeres combined: 1/1.5; 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 unicoloured, shiny, black; widest at base, width distinctly narrower compared to width of elytral base at humerus; anterior marginal line not interrupted medially, posterior marginal line absent; lateral margin not serrated, generally bent at middle, otherwise straight, behind anterior angles weakly concave, posteriorly straight; setae of lateral margin sparse; basal margin evenly curved; transverse impression beside basal margin present only laterally; 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 moderately dense, simple and fine, without well-defined impunctate areas. Scutellum without punctures.
Elytra unicoloured, black; surface 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 with half length as laterally; ultimate and penultimate apical ventrites simple and flat; apical ventrite short (as long as preceding ventrite); penultimate apical ventrite with row of setae like preceding one; beside the robust row of setae, almost glabrous. Pygidium strongly convex.
Legs blackish. Ratio of length of metepisternum/metacoxa:1/1.4. 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: 1/2.9; dorsal margin 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, as long as second; width ratio of first protarsomere vs second protarsomere: 1.5/1; second protarsomere narrow, but bent; 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 21 (c–d).
Female unknown.
Variation
Length: 6.2–6.8 mm. Elytral length: 4–4.4 mm. Width: 3.1–3.2 mm. Pronotum and elytra in paratype bicoloured: pronotum in basal half yellowish; elytra yellow with dark margins.
Diagnosis
Symmela nunesorum sp. nov. is in the shape of aedeagus very similar to S. capixaba. Symmela nunesorum differs by the pronotum which is distinctly narrower than the elytra at the humerus and its lateral margins bent at middle. Furthermore, S. nunesorum has a blackish body and the parameres are narrower at the apex (compared to body size, or length of phallobase). In S. capixaba, the body is yellowish brown and parameres are wider at the apex.
Etymology
This species is named after Rafael V. Nunes and Luis Gabriel de O.A. Nunes (not related); both are great Brazillian biologists and dear friends of the first author (noun in genitive case).
description: Published as part of Pacheco, Thaynara L., Wipfler, Benedict, Monné, Marcela L. & Ahrens, Dirk, 2022, The genus Symmela Erichson, 1835 (Coleoptera, Scarabaeidae, Sericini): taxonomy and phylogenetic analysis, pp. 607-705 in Journal of Natural History 56 (9 - 12) on pages 671-674, DOI: 10.1080/00222933.2022.2084649, http://zenodo.org/record/7012522