Symmela corumbana Moser, 1921

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 : 630-633

Symmela corumbana Moser, 1921

( Figures 6 , 29 (b), 30(f))

Symmela corumbana Moser, 1921: 137 (original description); Frey: 1973: 323 (key); Evans 2003: 48; Evans and Smith 2005: 30, 2007: 30, 2009: 30 (checklist)

Type material examined

Lectotype (here designated). ♂ ‘Corumba Matt. Grosso/ Symmela corumbana Type ♂ Mos./ Typus/ corumbana Mos. ’ ( ZMHB) . Paralectotypes: 1 ♀ ‘Corumba Matt. Grosso/ Symmela corumbana Type ♀ Mos./ Typus/ Symela [sic!] corumbana Moser [typewritten]’ ( ZMHB), 10 ♂♂, 6 ♀♀ ‘Corumba Matt . Grosso/ Symela [sic!] corumbana Moser [typewritten]’ ( ZMHB), 1 ♂ ‘Corumba Matt . Grosso/ S. corumbana det . G . Frey 1972’ ( ZMHB).

Additional material examined

Brazil: 2 ♂♂, 4 ♀♀ ‘ Brasilien Matto Grosso 200 engl Meilen v . Cuyaba C. Heller V.’ ( ZMHB) , 1 ♂, 1 ♀ ‘ Cáceres , MT 12.11 .1985 C . Elias leg . Polonoroeste / Dpto ZOOL UF Parana / DZUP 311512/ 34 Neotropical Sericini spec.’ ( DZUP) , 1 ♀ ‘ Cáceres , MT 12.11 .1985 C . Elias leg . Polonoroeste / Dpto ZOOL UF Parana / DZUP 311511’ ( DZUP), 1 ♂ ‘ Corumba Matt . Grosso / W . Muche Radeberg Ankauf’ ( ZFMK) . Paraguay: 1 ♂ ‘ Paraguay: San Pedro Cororo-Rio Ypane XII-1/4-1983 Malaise Trap M . Wasbauer coll ./ Dr. Alan R. Hardy 2005 donation to California Academy of Sciences’ ( CAS), 2 ♂♂, 1 ♀ ‘ Cerro Amambay Paraguay / Oct . 1939 A. Schultze / 35 Neotropical Sericini spec .’ ( USNM).

Redescription

Length: 4.5 mm. Elytral length: 3 mm. Width: 2.5 mm. Head blackish brown, shiny, with sparse setae directed posteriorly. Labroclypeus as wide as frons, subtrapezoidal; surface convex; 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 sparse; suture between labrum and clypeus invisible. Smooth area in front of eye distinctly separated from frons by a suture. Frons anteriorly flat, punctation irregular, sparse. Ocular canthus with terminal setae, ratio of length of ocular canthus/eye diameter: 1/3. Eyes evenly spherical, ratio of diameter/interocular width: 0.48. Antenna with eight antennomeres. Antennal club with three antennomeres, yellowish, straight; width of antennal lamella equal to width of antennomeres of funiculus; apical lamella subequal to basal and median ones; length ratio of antennal club vs remaining antennomeres combined: 1/1.1; length ratio of third vs fourth antennomere: 1/3; fourth antennomere without lateral projection; length ratio of fifth vs fourth antennomere: 1/5. Labrum anteriorly bluntly angled on each side, concave at middle. Setae on mentum moderately dense.

Head and pronotum without copper iridescent shine. Pronotum bicoloured, iridescent, brownish orange; 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 strongly 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 moderately dense, simple and fine, without well-defined impunctate areas. Scutellum without punctures.

Elytra bicoloured, blackish brown in major part, posterior half dark; 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 of same 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 weakly convex.

Legs yellow. Ratio of length of metepisternum/metacoxa: 1/1.26. 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: 1/3.06; 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 reduced to a single robust spine; 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 setose, ventral setae standing in a narrow line, fine, short; medial face glabrous. Protibia with two distinct teeth; spur curved interiorly. First protarsomere straight, its length subequal to second and third combined; width ratio of first protarsomere vs second protarsomere: 1/1; second protarsomere enlarged; third and fourth protarsomere elongate and narrow (distinctly longer than wide); fifth protarsomere circular in cross section, as long as 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 6 (d–f).

Figures

Figure 6. Symmela corumbana Moser, 1921, lectotype ♂. (a) Habitus, dorsal view; (b) habitus, lateral view; (c) labels; (d) parameres, dorsal view; (e) aedeagus, dorsal view; (f) aedeagus, lateral view. Scale bars: a, b = 1 mm; d–f = 0.5 mm.

Figure 29. Distribution map of the Symmela species.