Epicauta vittata

Campos-Soldini, María Paula & Roig-Juñent, Sergio Alberto, 2011, Redefinition of the vittata species group of Epicauta Dejean (1834) (Coleoptera: Meloidae) and taxonomic revision of the species from southern South America, Zootaxa 2824, pp. 21-43 : 22-23

Epicauta vittata group Adams and Selander, 1979

Diagnosis. Vitta expressed on underlying cuticle with a basic pattern from one to four vittae (Figs. 18 – 27). Fore tibia with a marked depression on inner apical third (as show by arrow in Fig. 1). Male gonoforceps incompletely sclerotized, apical portion membranous and largely unpigmented except for a Y-shaped sclerotization consisting of a narrow median strip which diverges apically and runs along the ventromedial surface of each parameral lobe ( Figs. 2–2 a).

Redescription. Moderate to large vittate beetles; maximum length varying from 7 to 23 mm. Pubescence of head, pronotum, and elytra: dense (28–34 setae by lineal mm) or sparse (13–19 setae by lineal mm). Pubescence of elytra mirrors color pattern of cuticle or not

Head and pronotum smooth to finely punctate. Head capsule with pale patches of different sizes or not (as in Figs. 12–17 ); frons impressed. Mouthparts labrum with distinct pale semicircular, central-apical spot, apical margin deeply emarginate; maxillary palpi large (three times the width), compressed dorso-ventrally, tapering to the base and expanding to apex (as in Fig. 7 ); labial palpi with segment III strongly expanded from the basal third to the apex ( Fig. 6 ), prementum with apical margin having ample concavity, or straight; (as show by arrow in Figs. 8– 9 ); mandible strongly curved to the apex, or relatively straight and gradually curved towards apex (as show by arrow in Figs. 10–11 ); eyes large, with anterior margin bisinuate, deep concavity in front of antennal insertions; ventral lobe having an ample concavity, tapering below, reaching mouthparts. Pronotum usually longer than wide and distinctly narrower than head, antero-lateral angles oblique, widest at apical third; lateral view with marked impression on apical third or relatively convex. Elytra with vittae expressed on the underlying cuticle, basic pattern from one to four vittae: pale vittae on a brown background or dark vittae on a pale background (Figs. 18–27). Fore tibia with a marked depression on inner apical third, apex of tibia with spine (shown by arrow, Fig. 1); hind tibial spurs subequal, robust, and truncate at apex, or acuminate and hollow with the inner spine rotated inwards. Dorsal blade of claws slightly curved from base to apex, ventral blade broader than dorsal near apical third; or dorsal blade of claws abruptly curved, ventral blade straight and much narrower and divergent. Pygidium narrowly emarginate, with apex incised or entire ( Figs. 3–5). Abdomen with last abdominal tergite twice wide, apex having a small median incision.

Male genitalia. Parameres incompletely sclerotized; parameral lobes at least twice as long as falobase, tapering to the apex, subparallel, separated at apical third, membranous and unpigmented except for a Y-shaped sclerotization which diverges apically and runs along the ventromedial surface of each paramere ( Figs. 2–2 a); basal region distinctly emarginate or not.

Female genitalia. Spermathecal capsule very well developed, spermathecal duct long and thin, with a large and tubular accessory gland; vagina large, ovariolas Y-form ( Fig. 28 ). Valvifer with ventrolateral basal stem large and straight; stylus with setae on apical third ( Fig. 28 a).

Included and excluded species: Adams and Selander (1979) examined in detail seven species ( E. abadona Skinner, 1904 ; E. occidentalis Werner, 1944 ; E. tamara Adams and Selander, 1979 ; E. temexa Adams and Selander, 1979 ; E. unilineata Champion, 1892 ; E. vittata ( Fabricius, 1775) and E. viticollis (Haag-Rutemberg, 1880)) from North America, two species ( E. apure Adams and Selander, 1979 ; E. aragua Adams and Selander, 1979 ) ranging from Central America to northern South America, and three species ( E. leopardina (Hagg-Rutember, 1880) , E. luteolineata Pic, 1933 ; and E. monachica (Berg, 1883)) from northern South America. They also mentioned 18 species ( E. borgmeieri Denier, 1935 ; E. bosqi Denier 1935 ; E. clericalis ( Berg, 1881) , E. floydwerneri Martínez, 1955 ; E. franciscana Denier, 1935 ; E. fulginosa ( Oliver, 1795) , E. grammica ( Fischer, 1827) , E. kraussi (Haag- Rutemberg, 1880), E. purpureiceps ( Berg, 1889) , E. missionum ( Berg, 1881) , E. nattereri (Hagg-Rutemberg, 1880) , E. philaemata ( Klug, 1825) ; E. rutilifrons Borchmann, 1930 ; E. strigata ( Gyllenhal, 1817) , E. subvittata ( Erichson, 1848) , E. xanthocephala ( Klug, 1825) , E. yungana Denier, 1935 ; and E. zebra (Dohrn, 1876)) from South America. Pinto (1991) examined eight species from North and Central America ( E. abadona Skinner, 1904 ; E. aragua Adams and Selander, 1979 ; E. occidentalis Werner, 1944 ; E. tamara Adams and Selander, 1979 ; E. temexa Adams and Selander, 1979 ; E. unilineata Champion, 1892 ; E. vittata ( Fabricius, 1775) and E. viticollis (Haag-Rutemberg, 1880)) , but did not provide any information on South American species.

The elytra with the vittate pattern expressed on underlying cuticle is a unique chracteristic within this genus and could be considered a synapomorphic character for the E. vittata group. Other characters that appears as exclusive within Epicauta to the vittata group are the marked depression on inner apical third of fore tibia; male gonoforceps incompletely sclerotized on apical portion, membranous and largely unpigmented, except for a Y-shaped sclerotization.

We excluded eight species that lack these exclusive characters of the group: E. borgmeieri Denier, 1935 , E. floydwerneri Martínez, 1955 , E. franciscana Denier, 1935 , E. fulginosa ( Olivier, 1795) , E. kraussi ( Haag-Rutemberg, 1880) , E. purpureiceps ( Berg, 1889) , E. philaemata ( Klug, 1825) , E. purpureiceps ( Berg, 1889) , E. rutilifrons Borchmann, 1930 and E. yungana Denier, 1935 , E. zebra ( Dohrn, 1876) . The species having these characters are: E. bosqi Denier, 1935 ; E. clericalis ( Berg, 1881) ; E. grammica ( Fischer, 1827) ; E. leopardina ( Haag-Rutemberg, 1880) ; E. luteolineata Pic, 1933 ; E. missionum ( Berg, 1881) ; E. monachica ( Berg, 1883) ; E. nattereri , E. rutilifrons Borchmann, 1930 ; E. strigata ( Gyllenhal, 1817) , E. subvittata ( Erichson, 1848) , and E. xanthocephala ( Klug, 1825) , plus other two species: E. excavata ( Klug, 1825) ; and E. semivittata ( Fairmaire, 1875) .

We revised the ten species mentioned by Adams and Selander (1979): E. bosqi Denier, 1935 ; E. clericalis Berg, 1881 ; E. excavata ( Klug, 1825) ; E. grammica ( Fischer, 1827) ; E. leopardina ( Haag-Rutemberg, 1880) ; E. luteolineata Pic, 1933 ; E. missionum Berg 1881 ; E. monachica ( Berg, 1883) ; E. rutilifrons Borchmann, 1930 ; and E. semivittata Fairmaire, 1875 . All them have the synapomorphic character and are found in southern South America.

Courtship and behavior: Courtship and behavior of seven species of the E. vittata group from North America and three of South America ( E. leopardina , E. luteolineata , and E. monachica ) were described in detail by Adams and Selander (1979). Courtship and behavior are unknown for the other species herein treated.

Distribution: The species studied herein are distributed in the Chaco, a subregion ranging from southern Bolivia, western Paraguay, southern Brazil, and central and northern Argentina ( Cabrera, 1971; Cabrera and Willink, 1973; Morrone, 1996, 2000). According to Morrone (1996, 2000), this biogeographical subregion is subdivided into five provinces; three of which correspond to the distribution of Epicauta : Chaco, Pampa and Monte. These biogeographical provinces are characterized by dry shrub or forest, and grasslands or steppes.

Figures

FIGURE 28. Female genitalia: (a) spca: spermathecal capsule; (b) ga: accessory gland; (c) spdu: spermathecal duct; (d) ca: calyx; (e) ov: ovary; (f) va: vagina; (g) va: valvifer; (h) stylus; (i) bsva: ventrolateral basal stem.

FIGURES 12 – 17. Head cuticle color: 12. E. excavate; 13. E. semivittata, E. missionum; 14. E. clericalis, E. luteolineata; 15. E. bosqi; 16. E. leopardina, E. monachica, E. rutilifrons; 17. E. grammica.

FIGURES 6 – 11. Epicauta lopardina, 6. Labial palpi with segment III strongly expanded from the basal third to the apex; 7. Maxillary palpi large (three times width) compressed dorso-ventrally, tapering to the base and expanding to apex. E. leopardina: 8. Prementum with central area having ample concavity; E. clericalis: 9. Prementum straight. Mandible dorsal views: E. leopardina: 10 (b, see arrow); E. clericalis 11 (b, see arrow).