Minotauros Hall

Hall, Jason P. W., 2007, Two new genera in the Nymphidiina (Lepidoptera: Riodinidae: Nymphidiini), Zootaxa 1415, pp. 35-42 : 39-42

Minotauros Hall , n. gen.

( Figs. 2 A,B; 4; 6)

Type species: Lemonias lampros Bates, 1868 .

Etymology: The name of this genus is based on the monster from ancient Greek mythology with the head of a bull and the body of a man, in reference to the dorsally bifurcate male genital uncus of the type species.

Description: MALE: Forewing length 11–14 mm. Wing shape: Both wings slightly elongate; distal margin of forewing prominently convex, costal and anal margins slightly convex (anal margin of M. lampros curled in Fig. 2 A); hindwing rounded. Venation: As in Livendula , four forewing radial veins. Dorsal surface: Ground color of both wings brown overlaid with dark blue scaling on both wings in M. lampros , and rufousbrown scaling on forewing and costal half of hindwing and white scaling on anal half of hindwing in M. charessa (Stichel, 1910) ; three black spots in discal cell of both wings, two black spots at base of cell Cu2, jagged band of black postdiscal spots and smooth band of small black submarginal spots lined proximally with whitish scaling in M. charessa , postdiscal and basal spots on hindwing barely visible, all dorsal black spots more prominent in M. charessa ; M. lampros with a well-defined, raised, oval pad of dark yellow androconial scales in middle of hindwing costal margin, and M. charessa with a more poorly defined patch of rufous-brown androconial scales in same position; forewing fringe brown, hindwing fringe brown in M. lampros and largely white in M. charessa . Ventral surface: Differs from dorsal surface in following ways: Ground color pale yellowish brown in M. lampros , and a paler version of dorsal surface in M. charessa ; M. charessa with a poorly defined patch of rufous-brown androconial scales at middle of forewing anal margin; dark spots surrounded by yellowish scaling in M. lampros and whitish scaling in M. charessa , spots more prominent on both wings in M. lampros and on hindwing in M. charessa .

Head: Labial palpal segments yellow at base and brown distally in M. lampros , and pale brown dorsally and dark brown ventrally in M. charessa , second and third segments elongate; eyes brown and bare, with pale scaling at margins; frons brown with yellow scaling ventrally in M. lampros , and whitish scaling in M. charessa ; antennal length approximately 60% of forewing length, segments brown with pale scaling at base, nudum along inner ventral margin of shaft prominent; clubs black, tips orange brown.

Body: Dorsal surface of thorax and abdomen dark brown and ventral surface pale brown in M. lampros , and dorsal surface of thorax rufous brown and ventral surface pale brown in M. charessa (removed abdomen of unique holotype was probably white); eighth sternite of M. lampros a simple rectangle with a very small distal indentation (eighth sternite shape in M. charessa unknown); all legs brown with yellow scaling in M. lampros , and whitish in M. charessa , tarsus of foreleg unimerous, coxa of medium length for family, midleg and hindleg with a tibial spur and a group of spines at inner distal tip of tibia and spines along inner margin of all tarsal segments.

Genitalia ( Fig. 4 ): Uncus in M. lampros approximately rectangular in lateral view, with a prominently bifurcate dorsal posterior margin and a pair of elongate, ventrally and inwardly directed projections at ventral margin, uncus in M. charessa plain and approximately rectangular in lateral view, lateral “window” dorsally separated; falces of average size and shape for family; vinculum sinuate and slightly enlarged medially, saccus absent; valvae narrow, elongate, and approximately rectangular, with an elongate basal lateral bulge, valvae fused dorsally at posterior tips, posterior tip of each valve in ventral view in M. lampros with a narrow and apically downturned process; aedeagus short and of medium width, with pointed posterior tip opening dorsally and to right, and rounded anterior end opening to right, lip of posterior tip curled to right in M. lampros ; everted vesica of M. lampros short and broad, with one short membranous process at dorsal base of vesica and another more posteriorly at ventral margin, and a single long, ventrally directed, “blade”-like cornutus that projects away from membrane towards anterior tip, uneverted vesica of M. charessa (as illustrated by Stichel (1910–11 )) with a continuous row of about eleven small cornuti and a single larger cornutus anteriorly; pedicel of M. lampros posteriorly elongate with sclerotized lateral margins, pedicel of M. charessa simple and strap-like.

FEMALE ( M. lampros only): Differs externally from male in following ways: Both wings slightly more rounded; ground color of both wings pale and slightly rufous brown; a broad, cream colored, postdiscal band on hindwing extending from middle of anal margin to near apex crisply defined on dorsal surface and more diffusely defined on ventral surface; diffuse cream scaling present distal to postdiscal band on ventral forewing, yellow-white scaling in association with submarginal spots more prominent on both wings.

Head: Second and third palpal segments slightly more elongate.

Body: Foreleg with spines at inner distal tip of tibia and tarsal segments one to four.

Genitalia ( Fig. 6 ): Corpus bursae elongate, with a pair of posteriorly positioned, medium-sized, spine-like signa; ductus bursae broad and membranous, with a short, broad and flattened sclerotized section at posterior tip; membranous ductus seminalis exits ductus bursae on dorsal right side immediately before sclerotized section; ostium bursae consists of a broad and flattened sclerotized section enveloping sclerotized section of ductus bursae, with a narrowly elongate and round-tipped sclerotized projection from middle of dorsal posterior margin, and an inverted “T”-shaped sclerotized pad on abdominal surface; papillae anales approximately rectangular.

History of classification: The two species placed here in this new genus were described in Lemonias and Echenais , and treated in two different species groups of Echenais by Stichel (1910–11, 1930–31). Not previously recognized as being close relatives, lampros Bates, 1868 , and charessa Stichel, 1910 , are here transferred to Minotauros (n. combs.) from Adelotypa . The female of M. charessa remains unknown, whilst the female of M. lampros was only recently discovered, and is associated with the male for the first time here.

Diagnosis and systematic position: The genus Minotauros is erected here primarily for lampros , and the placement of charessa in Minotauros can only be tentative at the present time. In a family that is full of extraordinary rarities, M. charessa is one of the most poorly known species. It was described nearly a hundred years ago from a single male specimen collected on the Rio Juruá in western Brazil (Stichel, 1910), and to my knowledge has never been collected again. In addition, the abdomen of the holotype, housed in the Zoologisches Museum of the Humboldt Universität, in Berlin, Germany (ZMHU), was long ago removed for dissection, and may well be lost. Despite repeated searches of the ZMHU by myself and museum staff, no trace of the genitalia dissection has ever been found. Although the male genitalia of the holotype were, very unusually, illustrated by Stichel (1910–11), his illustration is somewhat stylized and almost certainly not entirely accurate. As a consequence, knowledge of the genital morphology of M. charessa remains incomplete. Stichel’s illustration does indicate the presence of numerous small cornuti in the uneverted vesica, and a small process on the valvae that are not present in M. lampros . The wing coloration of M. charessa also differs from that of M. lampros , but because M. charessa shares several unusual wing characters with M. lampros , I place it for now in Minotauros .

Minotauros lampros possesses numerous unique apomorphies, including a dark royal blue dorsal wing pattern, a prominent raised pad of yellow androconial scales across the middle of the costal margin on the dorsal hindwing (ultrastructure illustrated by Hall & Harvey (2002b)), a prominently bifurcate posterior margin to the uncus, a pair of elongate, ventrally and inwardly directed projections at the ventral margin of the uncus, a unique valve shape, a laterally curled posterior lip to the aedeagus, a very large, blade-like aedeagal cornutus, a posteriorly projecting and laterally thickened pedicel, and a unique arrangement of sclerotized structures in the vicinity of the female genital ostium bursae. Minotauros lampros and M. charessa have very similar wing shapes and spotting patterns on both wings, and share a convex forewing anal margin, which is found elsewhere in the Nymphidiina only in the unrelated “ Setabis ” tapaja (Saunders, 1859) and an undescribed relative. They also share a prominently visible patch of androconial scales along the costal margin of the dorsal hindwing, which is found elsewhere in the Nymphidiina only in the unrelated Pandemos pasiphae (Cramer, 1775) . As outlined in the diagnosis for Livendula , the species of Minotauros appear to be most closely related to those of Livendula .

Distribution: Both species of Minotauros appear to be largely confined to the lowlands of the western Amazon, with an outlying record of M. lampros from the mountains of southern Guyana.

Figures

FIGURES 1 – 2. Adults (dorsal surface on left, ventral surface on right). 1 A. Livendula huebneri male, nr. Cacaulândia, S. W. Brazil [Ro] (USNM). 1 B. Livendula huebneri female, nr. Cacaulândia, S. W. Brazil [Ro] (USNM). 2 A. Minotauros lampros male, Estación Científica Yasuní, E. Ecuador (JHKW). 2 B. Minotauros lampros female, Estación Científica Yasuní, E. Ecuador (JHKW).

FIGURES 3 – 4. Male genitalia. 3. Livendula huebneri, Matoury, French Guiana (USNM), with genitalia and cornutus (bottom) in lateral view, and valvae in ventral view (top). 4. Minotauros lampros, upper Río Tiputini, E. Ecuador (JHKW), with genitalia in lateral view, valvae in ventral view (left) and uncus / tegumen in dorsal view (right). Scale bar = 1 mm.

FIGURES 5 – 6. Female genitalia in dorsal view. 5. Livendula huebneri, Parque Nacional Manu, Pakitza, Peru (USNM). 6. Minotauros lampros, Mitú, Colombia (AME). Scale bar = 1 mm.