Ora atroapicalis Pic, 1928

Libonatti, María Laura, 2015, A revision of the genus Ora Clark, 1865 (Coleoptera: Scirtidae) in Argentina (part II) — redescriptions, updated distributions and a key to species, Zootaxa 3985 (1), pp. 69-97 : 70-75

Ora atroapicalis Pic, 1928

( Figs. 1–4 , 26–43 )

Ora atroapicalis Pic, 1928: 9

Type material. Holotype: ♂ ( MNHN), “? Brésil ” [white label, handwritten by Pic], “ Ora / atroapicalis n sp” [white label, handwritten by Pic], “ HOLOTYPUS / Ora atroapicalis / Pic, 1928 ” [red label, printed].

Additional material studied. ARGENTINA: 1 ♀ (BR), “R EP ARGENTINA / Pr. Santiago d. Estero / 190 / C. Bruch” [white label, printed], “ Ora / atroapicalis / Pic” [white label, handwritten by Bruch], “ Ora / atroapicalis / Pic” [white label, handwritten by Pic]; 1 ♂ ( MACN), “ SANTA FE / IV-61 / WILLINER-S.J.” [white label, printed/ handwritten]; 7 ♂ ( MLLC), Formosa, PN Río Pilcomayo, Estero Poí, 16.i.2011, light trap, M. C. Michat; 4 ♂ and 2 ♀ ( MLLC), Chaco, ~ 200 m from PN Chaco, 18.i.2011, light trap, M. C. Michat; 1 ♂ and 1 ♀ ( MLLC), Corrientes, 28º 3’ 39” S 58º 9’ 32” W, 10.xii.2012, light trap, M. C. Michat & P. L. M. Torres; 3 ♂ ( MLLC), Corrientes, RN del Iberá, Galarza, 18. iv.2013, light trap, S. A. Mazzucconi; 2 ♀ ( MLLC), Entre Ríos, PN El Palmar, 16.xi.2014, light trap, M. C. Michat; 1 ♂ ( MLLC), Entre Ríos, PN El Palmar, 17.xi.2014, light trap, M. L. Libonatti. PARAGUAY: 1 ♀ ( MACN), “PERIBEBUY / PARAGUAY / 4-I-66 / WILLINER” [white label, printed/ handwritten]; 3 ♂ and 1 ♀ ( MLLC), Canindeyú, Reserva Natural del Bosque Mbaracayú, Aguará Ñu, 14.xii.2003, light trap, O. Di Iorio.

Diagnosis. Body oblong-elongate, reddish testaceous, antennae, legs (except coxae and bases of femora), apical half to third of elytra and apical half of abdomen dark brown to black ( Figs. 1–3 ); tegmen asymmetrical, with base elongate and a pair of parameres, a shorter slightly curved digitiform right-handed paramere, and a longer strongly curved apically acute left-handed paramere ( Fig. 33 ); penis strongly asymmetrical, dorsoventrally flattened, curved ventrally, base more or less rectangular, with a distinct right-handed appendix connected distally to a short thin projection ( Fig. 34 ); anterior part of bursal sclerite flat with a single minute tooth and a broadly rounded-emarginate margin, middle part with a single tooth ( Fig. 42 ); prehensor elongate, curved, conical ( Fig. 43 ).

Redescription. Measurements. Males (n = 10): TL 3.78–4.63 [3.94] (mean 4.22) mm, PL 0.73–0.85 [0.73] (mean 0.78) mm, PW 1.70–2.01 [1.70] (mean 1.78) mm, EL 3.28–3.86 [3.36] (mean 3.54) mm, EW 2.35–2.74 [2.35] (mean 2.57) mm. Females (n = 10): TL 4.09–5.70 (mean 4.75) mm, PL 0.73–0.85 (mean 0.80) mm, PW 1.66–1.97 (mean 1.80) mm, EL 3.47–4.36 (mean 3.77) mm, EW 2.39–2.82 (mean 2.57) mm.

Habitus. Oblong-elongate, depressed, maximum width at middle of elytra, closely covered with yellowish setae ( Figs. 1–3 ).

Coloration. Body reddish testaceous, except for the brown-black antennae, palpi, apical part of femora, tibiae, tarsi, apical half of abdomen and apical half to third of elytra.

Head. Wide, approximately 1.7x wider than interocular space, the pair of frontal foveae and the concave clypeal surface delimited by a lateral ridge on each side forming a trapezoidal fovea; punctation very fine, dense, punctures separated by 1.0–2.0x diameter. Antennae filiform, segments 1 and 2 barrel-shaped, segment 1 almost twice the length of segment 2, segment 3 subconical, approximately the same length as segment 2, segments 4–11 relatively wide, segment 4 twice the length of segment 3, subsequent segments gradually shortening until segment 10, segment 11 the same length as segment 4, apex rounded, apical margins of antennomeres 4–10 not projected anteriorly. Mandibles with acute apex.

Thorax. Pronotum approximately 1.6x wider than long, anterolateral angles sharply projecting anteriorly, lateral margins greatly rounded; punctation on pronotum and scutellar shield similar to that on head. Elytra depressed anterolaterally, humerus slightly marked, lateral margins rounded; punctation uniform, coarser than on head, pronotum and scutellar shield, punctures separated by 1.0–2.0x diameter. Mesoventral process elongate, parallel-sided, apex truncate to subtly notched. Approximate length ratio of metatarsomere 1: dorsal metatibial spur: ventral metatibial spur: 4.0: 3.0: 1.0.

Abdomen. Completely covered with short yellowish setae except for a pair of glabrous regions on ventrites 2– 5. Apex of ventrite 5 shallowly concave ( Figs. 26 , 39 ).

Male terminalia and genitalia. Tergite 8 with sclerotized apodemes converging posteriorly, basal part approximately straight, apical third curved inwards, plate subtrapezoidal with posterior margin distinctly arcuate and sclerotized, apical surface with setae ( Fig. 28 ). Sternite 8 not evident. Tergite 9 with a pair of sclerotized apodemes distinctly curved and converging posteriorly, plate more or less square-shaped with posterior margin almost straight, with a row of microtrichia ( Fig. 29 ). Sternite 9 elongate, apically bilobed, with a pair of sclerotized regions diverging posteriorly, posterior margin with setae and pores, central part with tufts of minute microtrichia ( Figs. 30, 31 ). Tegmen asymmetrical, with a pair of parameres, right-handed paramere elongate, almost straight, with digitiform apex and microsculpture consisting of pores and minute setae, left-handed paramere very elongate, very curved ventrally, with an acute apex and microsculpture consisting of minute setae ( Figs. 32, 33 ). Penis laminar, curved ventrally, strongly asymmetrical, base more or less rectangular, apical part with a right-handed appendix bearing distally a short and thin appendix ( Fig. 34 ).

Female genitalia. Anterior part of bursal sclerite laminar with a single minute tooth and a broadly roundedemarginate margin, middle part with a single tooth ( Figs. 41, 42 ). Prehensor elongate, curved, conical ( Figs. 41, 43 ). Microsculpture of bursella composed of rows of conical microtrichia.

Sexual dimorphism. Antennae broader in males than in females. Elytral setae longer in females than in males. Female elytron with two foveae near the apex: one short longitudinal depression adjacent to the suture and one oval depression located externally to the former, both closely covered with fine short setae (male lacking elytral foveae) ( Fig. 4 ). Tergite 7 with longer apodemes in females than in males, posterior margin parabolic in females and broadly rounded in males ( Figs. 27 , 40 ). Ventrite 5 with posterior concavity much deeper in males than in females ( Figs. 26, 38 ).

Intraspecific variation. Specimens vary in size and in the extent of the brown apical area on elytra ( Figs. 1, 2 ). Subtle differences in the degree of curvature of the left-handed lateral margin as well as in the length of the apical appendix of the penis were observed ( Figs. 34–38 ), although this variation is apparently continuous along the specimens studied so there is not enough evidence to recognize more than one species.

Distribution. Brazil. Paraguay. Argentina: Chaco, Corrientes, Entre Ríos, Formosa, Santa Fe and Santiago del Estero Provinces.

Remarks. The presence of elytral foveae in females (=excitators sensu Ruta 2008) is shared with O. sigmoidea Libonatti, 2014 , although these two species differ in body shape, color and genitalia. Ora atroapicalis is similar in body shape to O. sororum Pic, 1918 (from Brazil) and O. nigricornis Champion, 1897 (from Panamá), but differs in the dark brown apical part of the elytra. This is the only known Neotropical species of the genus with a distinct pair of parameres arising from the tegmen (the genitalia of O. sororum and O. nigricornis are unknown). This reinforces the idea proposed by Nyholm (1972) that the digitiform lobe of O. texana Champion, 1897 probably represents a paramere.

Figures

FIGURES 1 – 12. Ora spp. from Argentina, habitus. 1 – 4, Ora atroapicalis Pic, 1928: 1, holotype, male; 2, male from PN Chaco; 3, female from Aguará Ñu (Paraguay); 4, detail of female elytral apex; 5, O. bivittata Pic, 1922, male from Chaco Province; 6, O. bruchi Pic, 1928, lectotype, female; 7 – 12, O. depressa (Fabricius, 1801): 7, male from PN Mburucuyá (Corrientes); 8, female from Corrientes; 9, female from PN Mburucuyá; 10, female from PN El Palmar (Entre Ríos); 11, female from Piquete (Santa fe); 12, female from Rosario (Santa Fe).

FIGURES 26 – 38. Ora atroapicalis Pic, male. 26, holotype, abdomen, ventral aspect; 27, holotype, tergite 7; 28, holotype, tergite 8; 29, holotype, tergite 9; 30, holotype, sternite 9; 31, specimen from Estero Poí, sternite 9; 32, specimen from PN El Palmar, terminalia and genitalia, ventral aspect; 33, holotype, tegmen, dorsal aspect; 34, holotype, penis, ventral aspect; 35, m ale from PN Río Pilcomayo (Formosa), penis, ventral aspect; 36 & 37, males from RN del Iberá, penis, ventral aspect; 38, male from Santa Fe, penis, ventral aspect.

FIGURES 39 – 43. Ora atroapicalis Pic, female. 39, abdomen, ventral aspect; 40, tergite 7; 41, genital organs (except ovaries), dorsal aspect; 42, bursal sclerite, dorsal aspect; 43, prehensor, dorsal aspect. Abbreviations: bsa: bursa, bscl: bursal sclerite, bsl: bursella, gla: accessory gland, prh: prehensor.