Leucaniarivorum Guenée, 1852

Dolibaina, Diego Rodrigo, Casagrande, Mirna Martins, Specht, Alexandre, Mielke, Olaf Hermann Hendrik, Legrain, Albert, Zilli, Alberto & Goldstein, Paul, 2019, Taxonomy of the rivorum species-group of Leucania Ochsenheimer, 1816 (Lepidoptera: Noctuidae), Zootaxa 4711 (3), pp. 545-560 : 547-548

Leucaniarivorum Guenée, 1852

( Figs 1–4 , 17, 21 , 25 , 29 , 33, 37 , 41 )

Leucania rivorum Guenée, 1852: 82 .— Walker 1856: 98.— Hampson 1905: 512, 527, plate 93, fig. 1.— Poole 1989: 583, 585. Cirphis rivorum (Guenée) ; Draudt 1924: 165 (in part), plate 24d [4].

Diagnosis. Leucania rivorum can be distinguished from most of the New World Lecaunia by the pale rust and beige forewing, white-lined veins, a white spot at the end of discal cell bordered proximally by a black spot, a postdiscal row of minute black dots over the veins and an additional black dot below the origin of CuA 2 and the hind wing uniformly translucent white, including the fringe. In the male genitalia, the cucullus is triangular, longer than wide; ampulla narrow and long; sacculus rounded, distally narrowed and with a small indentation separating it from cucullus; distal portion of uncus enlarged dorso-ventrally and densely covered by long and robust setae both dorsally and ventrally; fultura inferior broad, rugose, and bearing a pair of erect short lateral rectangular projections, as far apart as the width at the base of cucullus; and vesica with several thin slender and pointed cornuti, wider than in L. multistria .

Redescription. Head: Predominantly rust colored, frons with a poorly defined transverse black band. Compound eyes globular, densely hairy. Labial palpus rust, short and upturned. Antenna filiform, dorsally cream-colored.

Thorax: Rust and beige, with two dorsal longitudinal grayish-black lines; patagium rust, with three transverse grayish-black bands; tegula beige with some black-tipped scales, lateral internal margin grayish-black; legs beige, black at base of meso- and metatibial spurs.

Forewing: Length 13.7–15.1 mm in males (n = 7), 13.8–17.8 mm in females (n = 4). About two and a half times longer than wider; costal margin nearly straight; apex rounded, neither produced nor falcate; outer margin slightly convex; tornus obtuse, rounded; anal margin slightly convex. Upperside ground color pale rust, beige at costal area, from discal cell extending by most of the space between R 4 and M 2 toward apex, and above 1A+2A; veins whitelined extending to fringe; white dot within inferior half of discal cell, bordered proximally by a black dot; discal area with a small black dot below origin of CuA 2; postdiscal arch-shaped row of minute black dots over all veins; dark brown midline along intervenular spaces between R 5 and 1A+2A, extending from postdiscal area to outer margin; fringe rust. Underside predominantly pearly beige; costal area pale rust speckled black scales; subapical black dots between R 1 -R 4, sometimes reduced; outer margin with small black dots in the space between R 3 and 1A+2A.

Hind wing: Ovoid; costal margin straight; apex rounded; outer margin convex; tornus obtuse, rounded; anal margin slightly convex. Upperside pearly white, weakly suffused with rust scales along costal area; outer margin with small black in the space between Rs–CuA 1; fringe white. Underside similar to upperside, but heavily suffused by rust and black scales along costal area; fringe rust at apex, otherwise white.

Abdomen: Beige with sparse black scales; two black lines crossing abdomen along pleura.

Male genitalia: Tegumen broad. Saccus V-shaped, about 3/5 as high as tegumen. Valva broad at base and gradually tapered towards apex, roughly twice as long as wide; sacculus broadly expanded and rounded along ventral margin, distally narrowed and fused with ventral surface of valva up to shallow indentation differentiating cucullus; editum triangular; clasper sub-rectangular, with short upcurved postero-ventral projection; ampulla narrow, as long as digitus, this narrow sickle-shaped, short, bent at base, then straight; costal sensory plate broad, ellipsoid; cucullus triangular, longer than wide, narrowed distally, feebly convex on dorsal edge, broadly-based and fused with main section of valva, without neck. Poma shield-like, wide transversely. Uncus slender, bent near the base, then straight, distal third enlarged dorso-ventrally and densely covered on both sides by long robust setae. Fultura inferior subrhomboidal, widest at base and rugous, with small paired, sharp apical processes and paired erect lateral projections, these ‘feather flag-shaped’ and widely separated from each other. Aedeagus nearly straight, with broad, swollen coecum, then gradually tapered up to middle, and with tubular distal half; opening of ejaculatory bulb at the beginning of the second third; insertion of manica at the distal third; distal margin with a short right dorso-lateral projection; vesica simple tubular, twisted to right, bearing two groups of cornuti, a bundle of three short needle-like cornuti before middle of vesica followed by gently sinuous row of around 40 longer, spiniform cornuti of approximately similar size. Subscaphium joined to tegumen by narrow arms.

Female genitalia: Sternum VIII entirely sclerotized and fused with tergum VIII, weakly sclerotized along midventral line; apophysis anterior slender, slightly curved, as long as apophysis posterior; ostium bursae wide, cupshaped at base of sternum VIII; ductus bursae about 3/5 length of bursa copulatrix, of uniform width, dorso-ventrally flattened, heavily sclerotized and corrugated, except by small right dorso-lateral membranous area at junction with corpus bursae in ventral view; appendix bursae opposite ductus bursae, derived from left side of cervix bursae, about as long as corpus bursae, deeply sclerotized and corrugated ventrally with ridges continuing from ductus bursae, membranous in distal third and dorsally; corpus bursae ellipsoid, membranous except for strongly corrugated and sclerotized cervical part. Papilla analis strongly sclerotized, sub-trapezoidal in lateral view, shorter than posterior apophysis, posterior edge smoothly concave, apex rounded; posterior apophysis uniformly slender and straight.

Geographical distribution and phenology. This species occurs in natural open environments such as grasslands from mid- to high elevations of the Atlantic Forest and Cerrado biomes in Brazil, and disjunctly in the eastern Andes of Peru and in an area of low altitude at the border between the Chaco and Atlantic Forest biomes in Paraguay ( Fig. 41 ). The record of L. rivorum from Tucumán ( Köhler 1947) probably refers to L. pampa , and the record of L. rivorum from Cuba ( Draudt 1924) is probably a misidentification of L. chejela .

This species was recorded almost throughout the year with the exception of July, November and December.

Comments. Leucania rivorum is a poorly known species, rarely mentioned in the literature. Although the original description does not include illustrations, the species was correctly identified by Hampson (1905), who figured a female from Brazil [from Rio de Janeiro state, deposited at the NHMUK and examined by us], well before the accession of Guenée’s type material at the British Museum (Natural History) via the Oberthür collection in 1927. Despite his accurate identification of that specimen, Hampson (1905) considered L. rivorum a senior synonym of L. pampa . Recently, L. rivorum was reported in studies conducted at several sites in Rio Grande do Sul, southern Brazil ( Specht & Corseuil 2002; Specht et al. 2004, 2005; Bernardi et al. 2011); however, these records are almost certainly incorrect given the distribution of L. rivorum south of Paraná, Brazil.

Among recent studies mentioning L. rivorum, Specht et al. (2004) compiled a list of Noctuidae in the Ceslau Biezanko Entomological Collection (CECB), where a species similar to L. macoya ( Schaus, 1921) had been identified erroneously as L. rivorum by Biezanko. The records of L. rivorum reported by Bernardi et al. (2011) belong to two distinct, unrelated and undescribed species found in southern Brazil (Dolibaina et al., in prep.). We were unsuccessful in our attempts to find the specimens identified as L. rivorum by Specht & Corseuil (2002) and Specht et al. (2005) at the MCTP, as no determination label with this name was found in their voucher material, and no specimens of L. rivorum were detected among MCTP material.

The wing pattern of L. rivorum is like that of several congeners and may be misleading, especially with respect to its close relative L. multistria . These two species are parapatric throughout most of their distributions, and sympatric only in a narrow zone in the Paraná state, corresponding to the southernmost limit of L. rivorum and the northernmost of L. multistria . Similarities in the male suggest a close relationship between these species, in particular in both species the fultura inferior bears a pair of erect lateral processes, which to our knowledge do not occur in any other American Leucania . The development of the costal sensory plate, which extends through most of the cucullus, is also shared by these two species, although a similar structure is also found in another American species, L. eyre ( Schaus, 1938) . The shape of the uncus differs markedly, in L. multistria it is narrowed apically, and dorsally setose as in most American Leucania ; whereas in L. rivorum the uncus is dorso-ventrally dilated and densely covered by setae before apex.

Type material. Guenée (1852) stated that the species was described from two males from Brazil in his collection, differing in wing color. One of the syntypes is deposited at the NHMUK with the following labels: / HOLO- TYPE/ 1. Leuc. Rivorum Gn. Gn. 115. Brésil lúnique individu sur lequel jai fait ma decription / Ex. Musaeo Ach Guénée / Ex Oberthür Coll. Brit. Mus. 1927-3. / Noctuidae BMNH(E) slide No. 24542 m #/ NHMUK010354047/.

The short text attached to the specimen “ holotype ” above may be translated as: “the only specimen on which I have made [or based] my description”. We were unable to locate the second specimen at the NHMUK, referred to by Guenée (1852). In order to ensure the stability of the name and to avoid misidentification with other similar species, the syntype “ holotype ” detailed above and deposited at the NHMUK is here designated as lectotype of L. rivorum , and the following labels will be added to it: / LECTOTYPUS / Lectotype Leucania rivorum Guenée, 1852 Dolibaina et al. des. 2019 /.

Material Examined. 24♂ and 14♀. PERU: Puno: Carabaya ( Tinguri ) , 1♂ and 1♀, collection W. Schaus ( USNM) . BRAZIL: 1♂, lectotype, 010354047 ( NHMUK). Distrito Federal: Planaltina , 1000m, 22.VIII.1996 , 2♂, V. O. Becker leg. 114742 ( VOB), ( CPAC) 1007m, 26.IX.2013 , 1♀, 11.X.2013, 1♀, 2.I.2014, 1♀, 16.IX.2014, 1♂, A. Specht leg. 725, 823, 749, 446 ( CPAC). Minas Gerais: Itambé do Mato Dentro ( Serra do Cipó , trilha da Farofa), 970m, 12.V.2011 , 1♀, Moraes & Marconato leg. ( MZUSP). Rio de Janeiro : 1♀, 010915000 ( NHMUK) , 2♂, Derg leg. 010915094, 010915095 ( NHMUK), 1♂ ( USNM) . Itatiaia, X.1928, 1♀, Pohl leg. ( MZUSP), 22.VI.1930, 1♀ , 24.IV.1930, 1♀ , Zikán leg. ( IOC), II.1937, 1♂ , Pohl leg. ( MZUSP). Nova Friburgo , 600m, 10.III.1993, 1♂ , 1100m, 21.I.1998, 1♂ , V. O. Becker leg. 86102, 112829 ( VOB). Petrópolis , 1♂ 010915093 ( NHMUK). São Paulo: Campos do Jordão , 1600-1900m, 20-27.II.2001, 1♂ and 1♀ , V. O. Becker leg. 130880, 130879 ( VOB). Piracaia , VII.1969, 1♂ , Bernardi leg. ( MZUSP). Salto Grande ( Paranapanema ), 1♂ , E. D. Jones leg. 010915001 ( NHMUK). São José do Barreiro ( Bocaína ), 1568m, 11-14.IV.2018, 1♂ and 3♀ , E. Joerke & C. Mielke leg. 482, 480, 481, 477 ( DD). São Paulo , 1♂ 010915092 ( NHMUK). Paraná : 1905, 1♂ , Janson leg. 010915344 ( NHMUK). Tibagi , 980m, 11-12.X.2018, 4♂ and 1♀ , Carneiro, Venâncio, Moreira & Orlandin leg. DZ 40.461, DZ 40.463, DZ 40.471, DZ 40.472, DZ 40.473 ( DZUP). PARAGUAY: Paraguarí: Sapucay , VI.1902, 1♂ , 23.II.1904, 1♂ , W. Forster leg. 010915096, 010914982 ( NHMUK).

Figures

FIGURE 41. Geographic distribution of the species of Leucania belonging to the rivorum species-group.

FIGURES 1–16. Male (left) and female (right) adults of Leucania species in dorsal and ventral views. Figs 1–4. L. rivorum, male from Tibagi, Paraná, Brazil (DZ 40.461), female from São José do Barreiro, São Paulo, Brazil (DD 477). Figs 5–8. L. multistria stat. rev., comb. nov., male from Tibagi, Paraná, Brazil (DZ 40.462), female from Cambará do Sul, Rio Grande do Sul, Brazil (DZ 40.449). Figs 9–12. L. pampa, stat. rev., male from Castro, Paraná, Brazil (USNM), female from São Francisco de Paula, Rio Grande do Sul, Brazil (MCTP 9962). Figs 13–16. L. chejela, male from Miranda, Mato Grosso do Sul, Brazil (CPAC 3951), female from Conquista D’Oeste, Mato Grosso, Brazil (DZ 40.516). Scale bar: 1cm.

FIGURES 17–24. Head and patagium of species of Leucania, in frontal (upper) and dorsal (bottom) views. Figs 17, 21. L. rivorum, Planaltina, Distrito Federal, Brazil (CPAC 446). Figs 18, 22. L. multistria, stat. rev., comb. nov., Cambará do Sul, Rio Grande do Sul, Brazil (DZ 40.389). Fig. 19, 23. L. pampa, stat. rev., São Francisco de Paula, Rio Grande do Sul, Brazil (MCTP 9962). Figs 20, 24. L. chejela, Miranda, Mato Grosso do Sul, Brazil (CPAC 3951).

FIGURES 25–28. Male genitalia of species of Leucania. Fig. 25. L. rivorum, Tibagi, Paraná, Brazil (DZ 40.471). Fig. 26. L. multistria, stat. rev., comb. nov., Tibagi, Paraná. Brazil (DZ 40.451). Fig. 27. L. pampa, stat. rev., Castro, Paraná, Brazil (USNM). Fig. 28. L. chejela, Conquista D’Oeste, Mato Grosso, Brazil (DZ 40.067). Left to right: posterior view of the genitalia; left lateral view of the right valva; lateral view of tegumen and uncus; dorso-posterior view of the uncus; posterior view of fultura inferior, poma and base of valvae. Lines and arrows indicate distinctive characters. Scale bar: 1mm.

FIGURES 29–32. Aedeagus and vesica of species of Leucania, in right lateral (upper) and dorsal (bottom) views. Fig. 29. L. rivorum. Fig. 30. L. multistria, stat. rev., comb. nov.. Fig. 31. L. pampa, stat. rev., upper is an amplified part of the vesica (out of scale), bottom is the dorsal view of the aedeagus without vesica (this structure broke up in the dissected male used in the plate). Fig. 32. L. chejela. Specimens are from the same localities of the figures 25–28. Scale bar: 1mm.

FIGURES 33–40. Female genitalia of species of Leucania, in lateral (Figs 33–36) and ventral (Figs 37–40) views. Figs 33, 37. L. rivorum, Planaltina, Distrito Federal, Brazil (CPAC 725). Figs 34, 38. L. multistria stat. rev., comb. nov., São Francisco de Paula, Rio Grande do Sul, Brazil (MCTP 9956). Figs 35–39. L. pampa stat. rev., Curitiba, Paraná, Brazil (USNM). Figs 36, 40. L. chejela, Chapadão do Sul, Mato Grosso do Sul, Brazil (CPAC 4510). Scale bar: 1mm.