Euphoria histrionica Species-Group

Orozco, Jesús, 2012, Monographic Revision of the American Genus Euphoria Burmeister, 1842 (Coleoptera: Scarabaeidae: Cetoniinae), The Coleopterists Bulletin (mo 11) 66, pp. 1-182 : 21-22

Euphoria histrionica Species-Group

(Appendix 3: Plate 1f–j )

Species in the histrionica species-group have a flattened and strigose frons, subquadrate to subtrapezoidal clypeus with apex and sides not raised, antennal club shorter than stem and subequal in length in both sexes, pronotal sides generally evenly rounded, protibiae not sexually dimorphic, striae mostly composed of lunulate punctures, venter without cretaceous markings, abdomen in males without longitudinal depression, and “typical” simple male genitalia.

With few exceptions, species in this group are difficult to separate based on adult morphology alone. The most useful character for species separation is the body sculpturing and vestiture (punctures, setae, cretaceous markings). The geographic distribution also aids in confirming the identification. While the male genitalia are useful to assign species to the group, they are of little use for species recognition within the group. The shape of the clypeus is also of no use for species diagnosis except in the case of E. subtomentosa (subtrapezoidal in contrast to quadrate as in the rest of the species).

Composition. Five species are included in this group: E. devulsa Horn , E. histrionica Thomson , E. levinotata Orozco new species, E. sonorae Bates , and E. subtomentosa (Gory and Percheron) .

Natural History. Adults of most species have been collected in the nests of Neotoma micropus Baird and Neotoma albigula Hartley ( Rodentia : Cricetidae ) or in the debris of ant nests.

K EY TO THE SPECIES OF THE HISTRIONICA SPECIES- GROUP

1. Clypeus subtrapezoidal ( Fig. 9b ). Cretaceous markings on elytra oriented longitudinally on striae ( Fig. 9a ). Mesometasternal process densely setose......................... E. subtomentosa (Gory and Percheron) (p. 27)

1′. Clypeus subquadrate. Elytra with or without cretaceous markings; markings never oriented longitudinally on striae. Mesometasternal process glabrous to setose..................................2

2. Scutellum impunctate, at most with a few punctures at base. Mesometasternal process wide, not strongly compressed laterally ......... ..................... E. histrionica Thomson (p. 23)

2′. Scutellum punctate. Mesometasternal process small, strongly compressed laterally.............3

3. Pygidium covered by cretaceous layer. Dorsal surface frequently densely setose ( Fig. 8a, d, e ). Cretaceous markings on elytra moderate to large, moderately dense ...................................... ................................... E. sonorae Bates (p. 26)

3′. Pygidium without cretaceous layer. Dorsal surface rarely densely setose. Cretaceous markings on elytra small, sparse ............... 4

4. Elytral striae bearing 3 evenly spaced rows of lunulate punctures ( Fig. 5a ). Pygidium at apex sexually dimorphic, rounded in males, acuminate in females ....... E. devulsa Horn (p. 22)

4′. Elytral striae bearing 3–4 irregular rows of grooves, double grooves, lunulate punctures, and geminate punctures ( Fig. 7a ). Pygidium at apex rounded in both sexes ...................... ..... E. levinotata Orozco , new species (p. 24)

C LAVE PARA LAS E SPECIES DEL G RUPO HISTRIONICA

1. Clípeo subtrapezoidal ( Fig. 9b ). Máculas cretáceas elitrales orientadas longitudinalmente sobre las estrías ( Fig. 9a ). Proceso mesometasternal densamente setoso ..... E. subtomentosa (Gory y Percheron) (p. 27)

1′. Clípeo subcuadrado. Élitros con o sin máculas cretáceas; máculas, cuando presentes, nunca orientadas longitudinalmente sobre las estrías. Proceso mesometasternal glabro o setoso...... 2

2. Escutelo sin punteaduras, cuando mucho con unas pocas en la base. Proceso mesometasternal ancho, no fuertemente comprimido lateralmente ......................... E. histrionica Thomson (p. 23)

2′. Escutelo punteado. Proceso mesometasternal pequeño, fuertemente comprimido lateralmente ........................................................................... 3

3. Pigídio cubierto por capa cretácea. Superficie dorsal frecuentemente densamente setosa ( Fig. 8a, d, e ). Máculas cretáceas elitrales grandes o medianas, moderadamente densas ............................. E. sonorae Bates (p. 26)

3′. Pigídio sin capa cretácea. Superficie dorsal raramente densamente setosa. Máculas cretáceas elitrales pequeñas, dispersas........................4

4. Estrías elitrales compuestas por 3 filas regulares de punteaduras lunuladas ( Fig. 5a ). Ápice pigidial sexualmente dimórfico, redondeado en machos, puntiagudo en hembras.............. .............................. E. devulsa Horn (p. 22)

4′. Estrías elitrales compuestas por 3–4 filas irregulares de surcos, surcos dobles, punteaduras lunuladas y geminadas ( Fig. 7a ). Ápice pigidial redondeado en ambos sexos ............................. ..... E. levinotata Orozco , especie nueva (p. 24)

Figures

Plate 1. Euphoria species. biguttata species-group: a, b) E. biguttata, c, d) E. canescens, e) E. dimidiata. histrionica species-group: f) E. devulsa, g) E. histrionica, h) E. levinotata, i) E. sonorae, j) E. subtomentosa. sepulcralis speciesgroup: k) E. boliviensis, l, m) E. leucographa, n) E. lurida, o, p) E. sepulcralis, q, r) E. yucateca. fulgida species-group: s, t) E. fulgida, u, v, w) E. limbalis, x, y) E. monticola.

Fig. 9. Euphoria subtomentosa. a) Habitus, b) Head, c) Parameres, d) Temporal distribution, e) Geographic distribution in Mexico.

Fig. 8. Euphoria sonorae. a) Habitus, b) Head, c) Parameres, d-e) Color variation, f) Temporal distribution, g) Geographic distribution in Mexico and the United States.

Fig. 5. Euphoria devulsa. a) Habitus, b) Head, c) Parameres, d) Temporal distribution, e) Geographic distribution in the United States.

Fig. 7. Euphoria levinotata. a) Habitus of paratype, b) Head of paratype, c) Parameres of paratype, d) Temporal distribution, e) Geographic distribution in the United States.