Hista hegemon ( Kollar, 1839 )

Moraes, Simeão S., Duarte, Marcelo & González, Jorge M., 2010, Revision of Hista Oiticica (Lepidoptera: Castniidae) and discussion on the validity of its subspecies, Zootaxa 2421, pp. 1-27 : 19-24

Hista hegemon ( Kollar, 1839)

( Figs. 40–54 , 67–78 )

Castnia hegemon Kollar, 1839: 217 , pl. 13, fig. 2 (taxonomy), lectotype 3 [designated by Lamas, 1995b: 248], BRAZIL, Rio de Janeiro (NMW) [photograph examined]; Walker, 1854: 26 (catalogue); Boisduval, [1875]: 514 (taxonomy); Butler, 1877: 5 (taxonomy); Westwood, 1877: 178 (taxonomy); Kirby, 1892: 7 (catalogue); Strand, 1913: 10, pl. 5b, fig. [2] (taxonomy); Dalla Torre, 1913: 10 (catalogue); Rothschild, 1919: 11 (taxonomy); Hoffmann, 1937: 164 (catalogue).

Castnia menetriesi Boisduval , [1875]: 511 (taxonomy), syntype 3, BRAZIL (BMNH) [photograph examined]; Westwood, 1877: 180 (taxonomy); Kirby, 1892: 7 (catalogue); Strand, 1913: 11 (taxonomy); Dalla Torre, 1913: 12 (catalogue); Rothschild, 1919: 12 (catalogue). New synonym.

Castnia dalmanii [sic] (nec Gray, 1838); Boisduval, [1875]: 512 (taxonomy); Westwood, 1877: 179 (taxonomy); Kirby, 1892: 7 (citation); Dalla Torre, 1913: 10 (citation).

Castnia satrapes ; Buchecker, [1880]: pl. 12, fig. 17 (taxonomy), syntype 3, BRAZIL [not examined; lost?]. Junior primary homonym of Castnia satrapes Kollar, 1839 .

Athis hegemon ; Houlbert, 1918: 290, 683 (taxonomy); Lathy, 1922: 76 (catalogue); Lathy, 1923: 225 (catalogue).

Athis menetriesi ; Houlbert, 1918: 297, 684, 710, pl. 453, fig. 3818 (taxonomy).

Castnia hegemon menetriesi ; Rothschild, 1919: 11 (taxonomy).

Castnia hegemon variegata Rothschild, 1919: 11 (taxonomy), holotype 3 (nec Ƥ) [fixed by evidence of monotypy], BRAZIL, Rio de Janeiro (BMNH). New synonym.

Hista hegemon ; Oiticica, 1955: 152 (taxonomy); Miller, 1995: 134 (catalogue); Lamas, 1995a: 77 (catalogue); 1995b: 248 (taxonomy).

Hista hegemon variegata ; Miller, 1995:134 (catalogue); Lamas, 1995a: 77 (catalogue).

Hista menetriesi ; Miller, 1995: 134 (catalogue).

Hista hegemon menetriesi ; Lamas, 1995a: 77 (catalogue).

History. Kollar (1839) described Castnia hegemon , type locality Rio de Janeiro, Brazil.

Boisduval ([1875]) described Castnia menetriesi , type locality Brazil. There is no evidence that this description was based on a unique specimen, although this is the most probable because Houlbert (1918: 297) mentioned finding only one male in the collection of Boisduval.

Boisduval ([1875]: 512) used the name Castnia dalmanni but the description referred to Castnia hegemon .

Rothschild (1919: 11) described Castnia hegemon variegata based on one specimen wrongly sexed as a female. Additionally, he proposed Castnia menetriesi as a subspecies of Castnia hegemon , but his evidence is actually an example of clinal variation.

Diagnosis. Forewing with maculae slightly darker than the ground color. Hindwing of light yellow hues medially, with two extradiscal spotband fused at tornus forming a “V” positioned horizontally.

Redescripion (male and female). Head. Identical to H. fabricii .

Thorax. Dorsally dark brown, prothorax and tegula slightly lighter, ventrally white. Coxa and trochanter white, other segments brown. Forewing subtriangular, outer margin rectilinear. Average wing length of 39 mm in males and 53 mm in females. Dorsal surface brown, darker at base, with three pale maculae, slightly darker than ground color; the upper macula being of elliptical contour and located at distal end of discal cell; the other two maculae being of subtriangular shape and located at postmedian region: one near apex and reaching vein M3, the other one near inner margin and reaching CuA1. These maculae are usually fused acquiring the form of a large postmedian band. Ventral surface orange with similar pattern of maculae as the dorsal surface. Hindwing with dorsal surface reddish orange, brown or pale brown, darker basally; discal cell white in females while in males there is a yellow area between M1 and 1A+2A and white between 1A+2A and the inner margin in males; showing two black extradiscal spotbands fused near the inner margin as a “V” positioned horizontally, sometimes with variable branches; inner band usually extending from Rs or M3 to 3A, and the outer band from Rs to M2 to 3A. Ventral surface reddish orange or pale brown with the same pattern of dorsal maculae but less marked.

Wing venation ( Figs. 67–68 ). Typical of the genus.

Abdomen. White dorsally with A1-A3 and A8 dark brown. Ventrally grayish with some gold admixed at the posterior margin of each sternite.

Male genitalia ( Figs. 69–75 ). Tegumen subrectangular in dorsal view. Uncus with three lobes; medial lobe longer than the lateral ones. Gnathos excavate posteriorly, dorsal and ventral arms sclerotized and fused anteriorly. Valva subtriangular, slightly rounded; upper margin slightly convex in the region of costa, lower margin parallel to the horizontal axis near the region of sacculus, and inclined posterodorsally, inner surface without ornamentation. Subscaphium weakly sclerotized. Subscaphium weakly sclerotized. Sacculus developed, consisting of a fold on the inner surface of the valva, oriented towards distal-medial axis. Saccus developed, with anterior projections rounded apically and uncurved. Juxta not immediately obvious. Aedeagus with distal lateral carina forming a flap, lacking spines; cornuti absent; coecum developed, longer than the wider diameter of the ejaculatory bulb foramen, usually ornamented with a ridge anteriorly.

Female genitalia ( Figs. 76–78 ). Eighth tergum with anterior margin concave, uniformly sclerotized, posteriorly with a triangular shape and an apex acute. Lamella antevaginalis weakly sclerotized. Lamella postvaginalis with posterior margin irregular. Anterior and posterior apophyses well developed; the former two fifths the length of the latter. Papillae anales sclerotized and bristled. Antrum membranous longer than wide. Ductus bursae with a spirally twisted portion near corpus bursae. Signa symmetric and ellipsoidal. Bulla seminalis globular and ornamented with scattered microspicules.

Ethology. Not much is known. Like H. fabricii , H. hegemon also whirls around trees as Sphingidae do ( Miller 1986). The flight period is usually from 11:30 to 13:00 overlapping with that of H. fabricii ( Miller 1986) . Also perches in stegopterous position and prefers to do this in sunny areas on small tree trunks and occasionally on bare twigs ( Miller 1986).

Distribution ( Fig. 54 ). Hista hegemon occurs mainly in the south and southeast of Brazil, with records for the states of Espírito Santo, Rio de Janeiro, São Paulo, and Santa Catarina.

Etymology. The specific epithet hegemon is a Greek word, which means leader.

Comments. Hista hegemon is sexually dimorphic. The females are larger than the males, and both sexes have different color pattern on the discal cell region of the hindwing. The females of H. hegemon are very rare and similar to those of Yagra dalmannii ( Gray, 1838) , differing from the later by the absence of a transverse white band on the forewing. The scarcity of H. hegemon in nature and in collections have been a problem for defining populations based either on morphological and color pattern variation or on geographical distribution.

Material examined: BRAZIL. Distrito Federal: Brasília, no date, 1 male ( CUIC). Espírito Santo: Colatina, Estação Nova Venecia, córrego do Sabiá, X-1936, 1 male ( MNRJ). Rio de Janeiro: no date, 1 male ( USNM); no date, 1 male ( FMNH); Nova Friburgo, no date, 1 male ( USNM); Nova Iguaçu, Tiguá, 14- XI- 1958, 1 male ( MNRJ); Rio de Janeiro, I-1909, 1 male ( MNRJ); idem, no date, 1 male, 1 female ( MNRJ), idem, no date, 2 males ( USNM), 1 male ( MZSP), 1 male ( DZUP); Rio de Janeiro, Floresta da Tijuca, estrada Paineiras, I-1925, 1 female ( FIOC); idem, I-1926, 1 male ( MNRJ); idem, XII-1926, 1 male ( MNRJ); idem, I- 1927, 2 males ( MNRJ); idem, I-1927, 5 males ( MNRJ); idem, I-1929, 1 female ( MNRJ); idem, I-1932, 1 male ( FIOC); idem, 12- I-1935, 1 male ( FIOC); idem, I-1937, 1 female ( MNRJ); idem, 15- I-1938, 1 male ( FIOC); idem, I-1938, 1 male ( MNRJ); idem, 20- I-1938, 1 female ( MNRJ); idem, I-1938, 4 males ( MNRJ), idem, 05- I-1939, 1 male ( MNRJ); idem,07- I-1948, 1 male ( MNRJ); idem, 25- I-1957, 1 male ( DZUP); idem, 15- I- 1960, 1 female ( DZUP); idem, 21- I-1975, 1 male ( DZUP); idem, no date, 1 male ( MNRJ), idem, no date, 1 male ( MZSP); Rio de Janeiro, Bairro da Boa Vista, 05- I-1971, 1 male ( DZUP); idem, 09- I-1978, 1 male ( DZUP); Rio de Janeiro, Gávea, 1918, 1 male ( MNRJ); Angra dos Reis, Japuiba, I-1935, 1 male ( MNRJ); idem, I/ II-1937, 2 males ( FIOC); idem, 10- VII-1937, 1 male ( FIOC); idem, I-1956, 1 male ( FIOC); Angra dos Reis, Jussaral, I/ II-1935, 3 males ( MNRJ), 1 male ( FIOC); idem, II-1937, 1 male ( MNRJ); idem, no date, 3 males ( MGCL). São Paulo: São Paulo, no date, 3 males ( MZSP); Guaraú- Peruíbe, 25- XII-1976, 3 males ( MZSP). Santa Catarina: São Bento do Sul, 900m, 13- III-2003, 1 male; Joinville, 15- I-1957, 1 male ( DZUP); idem, 23- XII-1978, 2 males ( DZUP); idem, no date, 1 male ( MNRJ); no locality, no date, 2 males ( USNM); idem, no date, 1 male ( MNRJ); idem, no date, 1 male ( MNRJ), 1 male ( DZUP). Unknown state (but Brazil as locality): no date, 2 males ( MGCL); no date, 1 male ( AMNH).

The validity of subspecies in Hista hegemon . The subspecies of Hista hegemon analyzed and dissected in this study were H. hegemon hegemon and H. hegemon variegata . The specimens dissected did not show variations for male genitalia (variation in females was not assessed because just one female was dissected). The study of H. hegemon menetriesi was possible only through photographs. For this reason, we examined only the wing color pattern of this subspecies.

Hista hegemon variegata was described by Rothschild (1919) from a single female that is deposited at BMNH. The author reported only one distinctive character in this form: the extension of extradiscal spotband in the dorsal surface of hindwing, which takes the form of “V” positioned horizontally near the outer margin.

In H. hegemon hegemon the extradiscal spotband is narrow and the internal arm of the “V” extends from the internal margin until vein CuA1 ( Figs. 40–41 ). In H. hegemon variegata the band is thicker and the internal arm of the “V” extends from the internal margin reaching vein Sc ( Figs. 48–49 ).

Although H. hegemon variegata had been described from a female specimen, we assessed variation only for males with the same pattern as described by Rothschild (1919) due to the fact that there were only two phenotypically identical females available for study. Furthermore, Dr. Gerardo Lamas (pers. comm.) searched for the female specimen described by Rothschild (1919), but only a male was found corresponding to the description of the subspecies ( Figs. 48–49 ). Rothschild (1919) must have erred in sexing the holotype of his variegata, as only a unique male was found in the BMNH, matching the original description.

The variation of the extradiscal spotband in the three subspecies may represent a smooth cline because there is a specimen that shows an intermediate phenotype between H. hegemon variegata and H. hegemon hegemon ( Figs. 42–47 ). The maculation on the ventral surface of the wings is also variable, but in this case the variation fits better in a random model than in a step cline ( Figs. 41, 43, 45, 47, 49 ). Also, the sympatry of these two forms ( Fig. 54 ) and the identical male genitalia morphology, plus the fact that the description of H. hegemon variegata is based on a single individual, makes the validity of this subspecies dubious.

The wing color pattern of Hista hegemon menetriesi resembles those of the two other subspecies, except by its darker hue ( Figs. 50–51 ). Despite this difference and the rarity of this form, the impossibility of dissecting specimens and absence of geographical data make questionable the status of subspecies for menetriesi .

Figures

FIGURE 54. Distribution of H. hegemon (Kollar, 1839) and variation of wing color in males. Although there are differences in extension of the hindwing extradiscal spotband, the different phenotypes may occur in a same locality.

FIGURES 40 – 51. Variation in wing color pattern of males of H. hegemon (Kollar, 1839). 40 – 41. H. hegemon (Kollar, 1839) Peruíbe, São Paulo, dorsal and ventral views, respectively. 42 – 43. H. hegemon (Kollar, 1839) Joinville, Santa Catarina, dorsal and ventral views, respectively. 44 – 45. H. hegemon (Kollar, 1839) Rio de Janeiro, Rio de Janeiro, dorsal and ventral views, respectively. 46 – 47. H. hegemon (Kollar, 1839) Timbó, Santa Catarina, dorsal and ventral views, respectively. 48 – 49. H. hegemon (Kollar, 1839) Rio de Janeiro, Rio de Janeiro. 50 – 51. Hista hegemon menetriesi (Boisduval, [1875]) Brazil. Scales 1 cm.

FIGURES 52 – 53. Hista hegemon (Kollar, 1839), female habitus. 52. Dorsal view. 53. Ventral view. Scales 1 cm.

FIGURES 67 – 68. Wing venation of H. hegemon (Kollar, 1839). 67. Forewing. 68. Hindwing. Scales 1 cm.

FIGURES 69 – 75. Male genitalia of H. hegemon (Kollar, 1839). 69. Aedeagus, lateral view. 70. Genitalia, lateral view. 71. Genitalia without valva, lateral view. 72. Tegumen and uncus, dorsal view. 73. Valva, internal view. 74. Genitalia, posterior view. 75. Saccus, ventral view. Scales 1 mm.

FIGURES 76 – 78. Female genitalia of H. hegemon (Kollar, 1839). 76. Dorsal view. 77. Ventral view. 78. Lateral view. Scales 1 mm.