Heteranassa Smith, 1899

Homziak, Nicholas, Hopkins, Heidi & Miller, Kelly B., 2015, Revision of the genus Heteranassa Smith, 1899 (Lepidoptera, Erebidae, Omopterini), ZooKeys 527, pp. 31-49 : 34-39

Taxon classification Animalia Lepidoptera Erebidae

Heteranassa Smith, 1899

Type species.

Homoptera mima Harvey, by subsequent designation by Nye 1975.

Taxonomy.

Heteranassa Smith, 1899: 105; Smith et al. 1903: 5; Barnes et al. 1917: 86; McDunnough 1938: 121; Kimball 1965: 130; Nye 1975: 239; Franclemont and Todd 1983; Poole 1989; Poole and Gentili 1996; Mustelin 2006: 7; Lafontaine and Schmidt 2010: 37; Zahiri et al. 2012: 118.

Diagnosis.

Heteranassa mima is now the only valid species in the genus. The genus and species can be distinguished from similar genera by the absence of spine–like setae on the mesothoracic tibia (Fig. 2) ( Smith 1899). The male genitalia (Figs 3, 4) serve to distinguish Heteranassa from other genera of Erebinae in the southwestern United States by the presence of a setose, membranous costal region of valves (Fig. 3) ( Franclemont 1986), and a “D” shaped, sclerotized saccular process connecting to the saccular region of the valves (Fig. 3). The female genitalia (Fig. 5) does not differ dramatically from other Omopterini . Male antennae fasciculate (Fig. 6), female antennae filiform. The proboscis (Fig. 7) is well-developed.

Specimens of Eubolina impartialis Harvey, Matigramma species, Acritogramma metaleuca (Hampson), Toxonprucha species and Coxina species are frequently misidentified as Heteranassa . Of these, Acritogramma metaleuca is the most similar to Heteranassa ( Franclemont 1986). Acritogramma metaleuca can be most easily distinguished by the presence of spine-like setae on the mesothoracic tibia, and there are also subtle differences in wing pattern ( Franclemont 1986). Acritogramma metaleuca has no brown lines or shading on the forewing, and the discal spot is distinctly lunulate. Eubolina impartialis is similar to both Heteranassa and Acritogramma metaleuca but has a brownish ground color on the hindwings, instead of grayish white, and spine-like setae on the mesothoracic tibia. From southern Texas into Mexico, Heteranassa may be confused with co–occurring Coxina species. This genus shows affinities to Heteranassa in forewing pattern and genitalia, but a lighter hindwing ground color serves to separate Heteranassa . Additionally, similarities in wing pattern and genital morphology suggest a relationship to the Caribbean and South American genus Elousa Walker. The ranges of Heteranassa and Elousa may overlap in southern Mexico. Elousa can be separated from Heteranassa by its smaller size, and the light gray to white mottling of the forewings. Toxonprucha species are generally smaller than Heteranassa , and they possess hindwings with a darker ground color and more distinct patterning than those of Heteranassa . A key to Heteranassa and similar species is provided below.

Taxonomic history.

Harvey (1876) described Homoptera mima from a single female from Texas, listing Belfrage as the source of the specimen. He referred the species to the genus Homoptera Guenée, but did not mention any characters used to determine generic placement. Grote (1882), in a checklist, moved Heteranassa mima to the genus Eubolina Harvey, 1875, again without any mention of characters used. Smith (1899) described Heteranassa fraterna and Heteranassa minor and placed these species in the genus Campometra Guenée, 1852. Campometra fraterna was described from a series of six lightly–marked specimens collected in Death Valley, California., and a single specimen from Catalina Springs, Arizona. Campometra minor was described from a series of five small female specimens collected in Arizona. Smith described these two species as new based on differences in size, coloration, and patterning. Smith (1899) proposed the genus Heteranassa to circumscribe Heteranassa mima , Heteranassa fraterna , and Heteranassa minor based on the absence of spine -like setae on the mesothoracic tibia in these three species. Smith (1899) wrote, "I prefer leaving them with Campometra temporarily, until all of the allied genera can be carefully studied, but suggest the term Heternassa in case generic separation seems desirable." These three species were formally referred to Heteranassa by Smith et al. (1903). Todd (1982) reviewed Smith’s type series and designated lectotypes for Heteranassa minor and Heteranassa fraterna . The pupa of Heteranassa was first described by Comstock (1955), and Crumb (1956) gave a description of the larva of Heteranassa .

In his study of southern California Noctuoidea, Mustelin (2006) determined Heteranassa minor to be a synonym of Heteranassa fraterna . He found no differences in genital morphology between the types of Heteranassa fraterna and Heteranassa minor ( Mustelin 2006). Mustelin (2006) did not examine the type specimen of Heteranassa mima , located in the Natural History Museum, London.

Description.

Adult male (Fig. 8): Head: front smooth scaled, vertex scales erect, elongate; labial palpi elongate, erect, three segments; area of frons behind labial palpi unscaled with domed center; antennae (Fig. 6) fasciculate, smooth scaled, conspicuous sensory setae on ventral surface; eyes smooth; proboscis well developed, coiled between labial palpi (Fig. 7). Thorax: smooth scaled dorsum; ventrally lighter; thick tuft of hairs arising below base of forewing. Legs: smooth scaled; prothoracic tibia with spatulate epiphysis, flattened hairs on ventral surface; mesothoracic tibia with thick tuft of scales, expanded distally, pair of spurs at distal end, spine-like setae absent; metathoracic tibia with pair of spurs mesially and at distal end; tarsi with three rows of spine-like setae. Forewing: 9.7-14.9 mm; antemedial line pointed apically on anal vein; medial line black, pointed mesially on radial, cubital, and anal veins; postmedial line black, outlining apical half of discal area; subterminal line brown, jagged, bordering lighter colored terminal area; terminal line scalloped outwardly at termini of veins, apical margin traced in lighter coloration; fringe scalloped apically at termini of veins; reniform spot markings range from white spot (Fig. 9), to thin white vertical dash (Fig. 10), to a barely visible dash (Figs 8, 11), or black (Fig. 12). Hind wing: ground color gray-white, darker shading distally; terminal line black, scalloped apically at termini of veins; fringe light gray, with dark shading between termini of M3 and CuA2 and between termini of 2A and 3A. Abdomen: segments 1 through 4 tufted dorsally. Genitalia (Figs 3, 4): Tegumen slightly excurved dorsally, lateral processes at distal end of each arm, process dorsally at distal end; uncus sparsely setose, curved, pointed; tuba analis membranous; scaphium sclerotized, tuba analis opening apically; juxta lightly sclerotized, excurved ventrally; transtilla membranous; vinculum U-shaped, mesial margin heavily sclerotized towards articulation with tegumen, widened in middle; valves conjoined basally, sclerotized basally, membranous distally; sacculus sclerotized; saccular process extended dorsally connected to membranous costal region; sclerotized part of valve with finger–like extension half distance from base; base of costa with a looped sclerite, connected to saccular process; aedeagus curved, narrowed apically, rounded anteriorly, dorsally sclerotized, ventrally membranous, dorsal surfaces undulating apically, apex pointed; ductus seminalis on ventral side; vesica membranous, without setae or cornuti, not elongated,four diverticula: one subbasal, two medial, and one apical. Adult Female: (Figs 7-10, 12) forewing length 11.0-16.7 mm. Exterior similar to male, except antennae filiform, mesothoracic tibiae not expanded distally. Genitalia: (Fig. 5) papilla analis membranous, rounded apically, setae stout, variable length; posterior apophysis extending just beyond anterior margin of 8th abdominal segment, apically curved inwards; anterior apophysis ca. 0.5 × length of posterior apophysis, paddle-shaped apex; anal tube: interior lining of anal tube with many rows of minute spines directed anteriorly on dorsal wall, ventral wall densely covered with shark-tooth-like tubercles; intersegmen tal membrane with many shark-tooth-like tubercles; 8th abdominal segment ringed with stout setae caudally; ostium bursae lightly sclerotized; antrum circular, membranous; ductus bursae reduced, membranous; corpus bursae elongate, membranous.

Eggs. Dark bluish gray, ~1/2 mm diameter; captured females laid eggs singly or in groups of less than five in crevices of host plant bark, or singly on sides of enclosing container.

Larvae. Variable in color; eggs developed into adults within five weeks; observations are consistent with Comstock (1955) and Crumb (1956). Larvae pupated before high-quality photographs could be taken.