Ora megadepressa, Libonatti, María Laura, 2014

Libonatti, María Laura, 2014, A revision of the genus Ora Clark, 1865 (Coleoptera: Scirtidae) in Argentina (part I) — descriptions of new species, Zootaxa 3884 (1), pp. 27-44 : 36-44

publication ID

https://doi.org/ 10.11646/zootaxa.3884.1.2

publication LSID

lsid:zoobank.org:pub:128B7D50-6F37-48ED-9773-1758B686EEA3

DOI

https://doi.org/10.5281/zenodo.5623525

persistent identifier

https://treatment.plazi.org/id/78D11119-54B8-47A0-9B50-806DB9AE3D93

taxon LSID

lsid:zoobank.org:act:78D11119-54B8-47A0-9B50-806DB9AE3D93

treatment provided by

Plazi

scientific name

Ora megadepressa
status

sp. nov.

Ora megadepressa sp. n.

Type material. Holotype: ♂ ( MACN), “ ARGENTINA: Corrientes / 28º 3’ 39” S 58º 9’ 32” W / 10.xii.2012, light trap / MC Michat & PLM Torres” [white label, printed], “ HOLOTYPUS / Ora megadepressa / Libonatti, 2014” [red label, printed]. Paratypes (all bearing same locality label as holotype and a yellow, printed label “ PARATYPUS / Ora megadepressa / Libonatti, 2014”): 2 ♂ and 1 ♀ ( MACN), 2 ♂ and 1 ♀ (NHM).

Diagnosis. Body broadly oval ( Figs. 23, 24 View FIGURES 22 – 29 ), hypomera and epipleura disctinctly broad; left-handed surface of the tegmen spiny ( Figs. 55, 57 View FIGURES 49 – 57 ), penis rod-shaped, straight in its major part, its base abruptly bent to the right hand side and its subapical projection right-handed and long ( Fig. 54 View FIGURES 49 – 57 ); bursal sclerite with markedly emarginate margin ( Fig. 62 View FIGURES 58 – 63 ), prehensor membranous, composed of numerous folds ( Fig. 63 View FIGURES 58 – 63 ).

Description. Measurements. Males (n = 5): TL 4.33–4.63 (mean 4.48) mm, PL 0.73–0.78 (mean 0.75) mm, PW 2.24–2.39 (mean 2.31) mm, EL 3.90–4.09 (mean 3.95) mm, EW 3.26–3.46 (mean 3.39) mm. Females (n = 2): TL 4.43 mm, PL 0.71–0.73 (mean 0.72) mm, PW 2.14–2.29 (mean 2.22) mm, EL 3.80 mm, EW 3.51 mm.

Habitus. Broadly oval, strongly dorsoventrally compresed, maximum width at basal third of elytra, closely covered with yellowish-brownish setae ( Figs. 23, 24 View FIGURES 22 – 29 ).

Coloration. Body yellow, head and pronotum somewhat brownish, elytra with many pale marks and a row of minute brown spots parallel to the elytral suture, antennae brownish, hind femur reddish.

Head. Wide, approximately 1.9x wider than interocular space, clypeal surface flat; punctation very fine, punctures separated by 2.0x diameter. Antennae subtly serrate, with apical margins of antennomeres 4–10 slightly projected anteriorly, approximate ratio of antennomeres: 1.4: 1.1: 1.0: 2.0: 2.0: 1.8: 1.8: 1.8: 1.6: 1.6: 1.8, approximate L/W ratios of antennomeres: 1.4, 1.4, 1.4, 2.5, 2.5, 2.3, 2.3, 2.3, 2.0, 2.0, 2.3. Mandibles with obtuse apex ( Fig. 4 View FIGURES 1 – 9 ).

Thorax. Pronotum approximately 3.3x wider than long, anterolateral angles sharply projecting anteriorly, lateral margins straight; punctation of pronotum and scutellum similar to that on head. Elytra lacking costulae, very depressed anterolaterally, humerus well marked, lateral margins fairly rounded, acuminate posteriorly; punctation composed of very fine puctures separated by 2.0–3.0x diameter, intermixed with coarse punctures twice the size and separated by 5.0–6.0x diameter; the fine punctures bearing shorter and more horizontal setae, the coarse punctures bearing longer and more erect setae, dark or light depending on the angle of light direction; elytra with a row of submarginal punctures parallel to elytral suture. Hypomera and epipleura very broad. Mesoventral process elongate, thin, with acute apex ( Fig. 12 View FIGURES 10 – 16 ). Approximate length ratio of metatarsomere 1: dorsal metatibial spur: ventral metatibial spur: 3.5: 3.1: 1.0.

Abdomen. Lateral and posterior parts of each abdominal ventrite covered with long setae, rest of the abdominal surface covered with short setae, except for the glabrous regions. Apex of ventrite 5 triangularly concave ( Figs. 49 View FIGURES 49 – 57 , 58 View FIGURES 58 – 63 ).

Male terminalia and genitalia. Tergite 8 with sclerotized apodemes converging posteriorly, posterior margin arcuate, with setae, pores and short microtrichia on central part and long microtrichia on apical margin ( Fig. 51 View FIGURES 49 – 57 ). Sternite 8 not distinct. Tergite 9 rounded, with a pair of sclerotized apodemes converging posteriorly, posterior margin with pores, setae and tufts of short microtrichia ( Fig. 52 View FIGURES 49 – 57 ). Sternite 9 apically bilobed, with a pair of sclerotized strips curved on inner side, posterior part with setae and pores ( Fig. 53 View FIGURES 49 – 57 ). Tegmen membranous, asymmetrical, with an apical digitiform outgrowth; microsculpture consisting of pores on the digitiform outgrowth, pores and minute setae throughout the basal part, and a spiny region on the left-handed side ( Figs. 54–57 View FIGURES 49 – 57 ). Penis asymmetrical, rod-shaped, major part straight, base abruptly curved to the right-handed side, subapical triangular process projected to the right-handed side ( Fig. 54 View FIGURES 49 – 57 ).

Female genitalia. Bursal sclerite: anterior part with one small spine and markedly emarginate margin, middle part with a pair of narrow spines ( Figs. 60–62 View FIGURES 58 – 63 ). Prehensor membranous with numerous folds ( Figs. 60, 63 View FIGURES 58 – 63 ).

Sexual dimorphism. Female with brown spots on head and pronotum, and with two groupings of short dark setae on elytra: one occupying an elongate portion of elytral surface situated at middle of elytral length adjacent to the elytral suture, and the other covering a rounded portion of the surface, approximately at the same level of the former one but more external ( Figs. 24, 25 View FIGURES 22 – 29 ). Tergite 7 more projected medially in females than in males ( Figs. 50 View FIGURES 49 – 57 , 59 View FIGURES 58 – 63 ). Ventrite 5 with posterior concavity much deeper in males than in females ( Figs. 49 View FIGURES 49 – 57 , 58 View FIGURES 58 – 63 ).

Etymology. This species is named megadepressa since it is very similar in habitus and morphology of male genitalia to Ora depressa ( Fabricius, 1801) but it is larger.

Remarks. The broadly oval, depressed body shape and the intermixed coarser punctures on elytra are shared with O. discoidea Champion (from Mexico, Guatemala and Honduras), O. marmorata Champion (from Panama, Trinidad and Brazil), O. mixta Champion (from Guatemala), O. obliqua Champion (from Mexico and Guatemala) ( Champion 1897), O. bivittata Pic (from Brazil), O. semibrunnea Pic (from Brazil), O. bruchi Pic (Libonatti, unpublished results) and O. depressa (Fabricius) (from South America) (Ruta, personal communication 2014). Ora megadepressa sp. n. differs from the other Neotropical species in its smaller TL/EW ratio and in the body color ( O. discoidea , O. obliqua and O. bivittata bear a brown vitta on each elytron, O. marmorata and O. bruchi exhibit brown maculated elytra, and O. semibrunnea has dark brown head and pronotum). The new species seems most closely related to O. depressa , recently redescribed by Ruta (2013). Both species share a rod-shaped penis with a subapical lateral projection. Differences between both species are summarized in Table 1 View TABLE 1 .

Type material. Holotype: ♂ ( MACN), “ ARGENTINA: Buenos Aires / Reserva El Destino / 26.xi.2012 / vegetated ditch / beating riparian trees / ML Libonatti” [white label, printed], “ HOLOTYPUS / Ora sigmoidea / Libonatti, 2014” [red label, printed]. Paratypes (all bearing yellow, printed label “ PARATYPUS / Ora sigmoidea / Libonatti, 2014”): 1 ♀ ( MACN), same locality label as holotype; 2 ♂ and 11 ♀ ( MACN), same locality label as holotype except 25.xi.2012; 1 ♂ and 1 ♀ (NHN), same locality label as holotype except 21.xi.2011.

Additional material studied. 1 ♀ (BR), “R EP ARGENTINA / Prov. Buenos Aires / XI. 1894 / C. Bruch” [white label, printed], “ Scirtes / brevenotatus / var. Pic” [white label, handwritten by Bruch], “ Scirtes / brevenotatus / var. Pic” [white label, handwritten by Pic]; 1 ♀ (BR): “R EP ARGENTINA / Prov. Buenos Aires / 189 / C. Bruch” [white label, printed]; 1 ♀ (BR): “R EP ARGENTINA / Prov. Buenos Aires / 190 / C. Bruch” [white label, printed]; 1 ♂ ( MACN), “Delta del Paraná - Río / Paraná de las Palmas / Estac. Exp. Agropec. INTA / Leg. Oliva A la luz” [white label, handwritten]; 1 ♂ ( MACN), “Delta del Paraná – Río / Sarmiento Leg. Oliva” [white label, handwritten]; 1 ♂ ( MACN), “Delta del Paraná - Río / Sarmiento / II.1976 / Leg. Oliva” [white label, handwritten]; 2 ♂ and 1 ♀ ( MACN), “Delta del Paraná - Río / Sarmiento / I.1977 / Leg. Oliva” [white label, handwritten].

Diagnosis. Size relatively large, body elliptical, broad, elytral color pattern composed of five basal pale spots, pale vittae and a black trifurcate subapical mark, elytra with four costulae ( Figs. 26, 27, 29 View FIGURES 22 – 29 ); tegmen with minute setae ( Fig. 73 View FIGURES 64 – 74 ), dorsal piece of penis laminar, with apical part and lateral margins spiny, apex obliquely truncate, ventral piece of penis sigmoid ( Fig. 72 View FIGURES 64 – 74 ); anterior margin of bursal sclerite with a semicircular emargination ( Fig. 79 View FIGURES 75 – 80 ), prehensor boxing-glove-shaped, with right-handed anterior part spiny ( Fig. 80 View FIGURES 75 – 80 ).

Description. Measurements. Males (n = 9): TL 4.92–5.55 (mean 5.29) mm, PL 0.78–0.97 (mean 0.90) mm, PW 2.00–2.29 (mean 2.10) mm, EL 4.14–4.92 (mean 4.51) mm, EW 2.92–3.56 (mean 3.32) mm. Females (n = 17): TL 4.87–6.02 (mean 5.50) mm, PL 0.78–1.02 (mean 0.92) mm, PW 2.00–2.53 (mean 2.28) mm, EL 4.14–5.65 (mean 4.82) mm, EW 2.98–3.70 (mean 3.40) mm.

Habitus. Elliptical, broad, depressed, maximum width at middle of elytra, closely covered with yellowish setae ( Figs. 26, 27, 29 View FIGURES 22 – 29 ).

Coloration. Head brown with a frontal V-shaped reddish testaceous mark between the eyes, mouthparts and antennomeres 1–2 testaceous, antennomeres 3–11 brownish testaceous, clypeus and labrum reddish testaceous. Pronotum brown, margins and a pair of central spots reddish testaceous, anterior and posterior margins with a medial triangular reddish testaceous mark extending a third to a quarter of the pronotal length. Scutellum brown with reddish testaceous margins. Elytra brown, basal quarter of elytra having at most five pale testaceous spots: one inverted L-shaped spot adjacent to the scutellum with its base along the anterior elytral margin, two contiguous spots located in a perpendicular line to the lateral margin of scutellum, one elongate spot on the humerus and a transversal spot on the lateral margin behind the humerus, second quarter of elytra light brown, with 2–3 testaceous stripes, posterior half of elytra light brown with an apical trifurcate black mark. Ventral surface brownish testaceous except for the brown apex of the posterior femur and tibia, and a pair of brown marks on the anterior margin of ventrites 2–5.

Head. Rather wide, approximately 2.0x wider than interocular space, clypeal surface convex; punctation fine, dense, punctures separated by 0.5x diameter. Antennae filiform, with apical margins of antennomeres 4–10 not projected anteriorly, approximate ratio of antennomeres: 2.0: 1.0: 1.6: 2.6: 2.6: 2.4: 2.4: 2.2: 2.2: 2.2: 2.2, approximate L/W ratios of antennomeres: 1.7, 1.3, 2.7, 4.3, 4.3, 4.0, 4.0, 3.7, 3.7, 3.7, 3.7. Mandibles with acute apex ( Figs. 5, 6 View FIGURES 1 – 9 ).

Thorax. Pronotum approximately 2.4x wider than long, anterolateral angles sharply projecting anteriorly, lateral margins rounded; punctation coarser than on head, punctures separated by 0.5–1.0x diameter. Scutellum with punctation somewhat coarser and more dispersed than on pronotum. Elytra depressed anterolaterally, humerus well marked, lateral margins rounded, with four costulae: the first (inner) costula beginning at the outer adscutellar testaceous spot, the second costula beginning at the apex of the inverted-L-shaped spot, the third costula beginning at the humerus and the fourth (outer) costula beginning behind the testaceous transverse spot, all of them ending at the apical dark spot; punctation uniform, coarser than on head, pronotum and scutellum, punctures separated by 1.0–2.0x diameter. Mesoventral process elongate, thin, with markedly notched apex ( Fig. 15 View FIGURES 10 – 16 ). Approximate length ratio of metatarsomere 1: dorsal metatibial spur: ventral metatibial spur: 3.1: 2.6: 1.0.

Abdomen. Completely covered with short yellowish setae except for a pair of glabrous regions on ventrites 2–5, coincident with the brown marks. Apex of ventrite 5 triangularly concave ( Figs. 64 View FIGURES 64 – 74 , 75 View FIGURES 75 – 80 ).

Male terminalia and genitalia. Tergite 8 with sclerotized apodemes converging posteriorly, with a sclerotized cross-piece, posterior margin arcuate, with setae on central part, short microtrichia on lateral parts and long microtrichia on apical margin ( Figs. 66, 67 View FIGURES 64 – 74 ). Sternite 8 more or less trapezoidal, weakly sclerotized, more heavily sclerotized along anterior margin ( Fig. 68 View FIGURES 64 – 74 ). Tergite 9 more or less square-shaped, with a pair of sclerotized apodemes converging posteriorly, posterior margin rounded, with a row of microtrichia ( Fig. 69 View FIGURES 64 – 74 ). Sternite 9 elongate, apically bilobed, with a pair of sclerotized apodemes more or less parallel-sided, almost meeting posteriorly, posterior margin with setae, central part with tufts of minute microtrichia ( Figs. 70, 71 View FIGURES 64 – 74 ). Tegmen membranous, slightly asymmetrical, with an apical left-handed digitiform outgrowth; microsculpture consisting of pores on the digitiform outgrowth, pores and minute setae throughout the medial part, and scale-like rows of minute microtrichia on the posterolateral part ( Figs. 73, 74 View FIGURES 64 – 74 ). Penis strongly asymmetrical, composed of two pieces: dorsal piece with a long and broad laminar appendix, with lateral margins more or less parallel-sided at base, abruptly and asymmetrically broadened at middle, then converging posteriorly to an obliquely truncate tip, surface near the tip spiny, left margin serrate throughout, right margin serrate along the apical two-thirds, ventral surface furrowed, dorsal surface crossed by two narrow, posteriorly pointed, strongly sclerotized strips; ventral piece sigmoid, ending in a strongly sclerotized, narrow, uniformly curved appendix ( Fig. 72 View FIGURES 64 – 74 ).

Female genitalia. Bursal sclerite: anterior part with one spine and arcuately emarginate margin, middle part with a pair of anterior relatively long spines with one minute spine in the middle and one posterior spine ( Figs. View FIGURES 75 – 80

77–79). Prehensor composed of one dorsal boxing-glove-shaped part with the right-handed basal surface covered with minute spines, and one ventral laminar oblong part ( Figs. 77, 80 View FIGURES 75 – 80 ).

Sexual dimorphism. Female elytra with two foveae near the apex ( Figs. 27, 28 View FIGURES 22 – 29 ): one short longitudinal depression adjacent to the suture and one rounded depression located externally to the former, both closely covered with fine setae; male lacking elytral foveae. Tergite 7 with a fringe of microtrichia along both lateral parts of the posterior margin in males (absent in females), with longer apodemes in females than in males, posterior margin arcuately projected in females and triangularly projected in males ( Figs. 65 View FIGURES 64 – 74 , 76 View FIGURES 75 – 80 ).

Intraspecific variation. Specimens vary in size and in the degree of maculation on elytra. Some specimens are lighter in color and bear four testaceous stripes on each elytron, each located on a costula. Some females have the elytra almost completely brown and the apical dark mark reduced ( Fig. 29 View FIGURES 22 – 29 ).

Etymology. This species is named sigmoidea in reference to the resemblance of the ventral part of the penis to the Greek letter sigma.

Natural history. Adults were collected by beating riparian trees (mainly Acacia sp.) near a small swamp containing fallen leaves in the bottom.

Remarks. The broad elliptical body, the basal pale maculation and the costulae of elytra are features shared with O. brevenotata ( Pic, 1915) (from Brazil) ( Fig. 81 View FIGURES 81 – 84 ). Pic apparently noticed the affinities between these species since the material in BR is labeled as a “variety” of O. brevenotata . Furthermore, the general shape of the aedeagus is similar in both species ( Figs. 82–84 View FIGURES 81 – 84 ), and also in O. texana Champion, 1897 (from southern USA) ( Nyholm 1972). However, differences between the aedeagi of the three species are notable and are summarized in Table 2 View TABLE 2 .

TABLE 1. Comparison of Ora megadepressa sp. n. and O. depressa Fabricius.

  Ora megadepressa (Figs. 54–57) Ora depressa (see Ruta 2013: Figs. 3A, 3B, 4)
Body shape Broader, smaller ratio TL/EW (mean: 1.13 for male, 1.17 for female); elytra acuminate posteriorly Narrower, higher ratio TL/EW (mean: 1.41 for male, female unknown); elytra not acuminate posteriorly
Color of elytra With pale marks Uniformly yellow
Tegmen Left-handed side with a spiny surface; basal part of digitiform outgrowth little narrowed Lacking spiny surface; basal part of digitiform outgrowth strongly narrowed
Penis Straight in most of its length, base abruptly curved to the right-handed side; subapical process longer and projected to the right-handed side Evenly curved along its length; subapical process shorter and projected to the left-handed side
Ora sigmoidea sp. n.  

TABLE 2. Comparison of Ora sigmoidea sp. n., O. brevenotata (Pic) and O. texana Champion.

  Ora sigmoidea (Figs. 72, 73) Ora brevenotata (Figs. 82–84) Ora texana (see Nyholm 1972: Fig. 4A)
Tegmen Digitiform outgrowth less protruding and more narrowed at base; surface covered with short setae Digitiform outgrowth more protruding and less narrowed at base; surface covered with long setae Digitiform outgrowth more protruding and less narrowed at base; setae unknown
Dorsal piece of penis Laminar, only lateral margins and apical part spiny, much more broadened than in O. texana , apex obliquely truncate, without lateral acute projection Not laminar, only the medial region spiny, acutely pointed posteriorly and with a lateral acute projection Laminar, only lateral margins and apical part spiny, much less broadened than in O. sigmoidea , apex acutely rounded, without lateral acute projection
Ventral piece of penis S-shaped in ventral aspect, much more curved than in O. texana , apical part not abruptly bent S-shaped in dorsal aspect, apical part abruptly bent S-shaped in ventral aspect, much less curved than in O. sigmoidea , apical part not abruptly bent
MACN

Museo Argentino de Ciencias Naturales Bernardino Rivadavia

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Scirtidae

Genus

Ora

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