Eucalantica Busck, 1904

Sohn, Jae-Cheon & Nishida, Kenji, 2011, A taxonomic review of Eucalantica Busck (Lepidoptera, Yponomeutidae) with descriptions of six new species, ZooKeys 118, pp. 75-96 : 77-79

Genus Eucalantica Busck, 1904 Figs 1-35

Eucalantica Busck, 1904: 750. Type species: Calantica polita Walsingham, 1881, by original designation and monotypy.

Diagnosis.

This genus is superficially similar to Thecobathra Meyrick, 1922, which also has a silvery white body and forewings, but differs from the latter in having a dark brown costal streak in forewing. The male genitalia of Eucalantica are distinguished from those of Thecobathra in having three or four spines on socii (none or one spine in the latter) and a lack of dentiform projections on phallus (present in the latter). The female S8 is entirely or almost entirely sclerotized in Eucalantica , but not in Thecobathra . The female genitalia of those two genera are also different in the shape of the signum, if present: keel-like or discoid plate in Eucalantica , cruciform in Thecobathra .

Description.

When resting, Eucalantica moths lay their body parallel to the substrate with their forelegs extended forward (Fig. 5).

Head.

(Fig. 1). Vertex vestiture rough with white, piliform scales; frons dark brown. Antennae filiform, 3/5 as long as forewing; scape white, with brown pecten; pedicel and first two flagellomeres with two complete whorls of scales per segment, white dorsally, gray ventrally; the remaining flagellomeres with a dorsal cover of gray scales on anterior half, a complete whorl of gray scales on distal half. Labial palpus porrect, 1st segment pale brownish gray, 1/4 as long as 2nd; 2nd segment dark brown, with denser scales distad, as long as eye diameter; 3rd segment white except dark brown on ventrobasal area, with white scale tufts dorsally, as long as 2nd. Maxillary palpus 4 segmented. Proboscis devoid of scales, longer than labial palpus.

Thorax and abdomen.

Tegula and mesonotum white. Foreleg lustrous dark brown dorsally, gray ventrally; epiphysis arising at middle. Midleg with coxa to tibia lustrous pale brown dorsally, silvery white ventrally; first tarsus dark brown dorsally, silvery white ventrally; the remaining tarsi brownish gray with dark brown ring on distal end. Hindleg silvery white, slightly tinged with pale brown ventrally. The forewings (Figs 6-14) white, elongate-triangular, costa straight, apex at anterior 1/3 of termen, obtuse-angled, termen oblique after apex; a black spot at the upper corner of discal cell; scattered black spots on the posterior 1/2 and distal 2/3; a brown or orange dorsal patch; however, the latter two are often reduced, depending on the individual. The forewing venation of Eucalantica (Fig. 2) with pterostigma 2/5 of costa before R; Rs1 and Rs2 stalked; Rs4 below apex; M2 and M3 at base closer than M1; CuA1 directed to tornus; CuA2 ending at posterior margin. The hindwing slightly broader than forewing, pale gray, darkened to apex and anterior margin, termen broadly round, apex narrowly round; venation (Fig. 2) with Sc+R1 ending at the middle of anterior margin; Rs directed to apex; M1, M2 and M3 evenly spaced; CuP close to 1A+2A. Abdomen silvery white, slightly tinged with pale brown on basal half; pleural lobe silvery white.

Abdominal sternum II and terga.

(Fig. 3). Apodeme slender, 1/5 as long as venula; venula slender, 4/5 as long as 2nd sternite; transverse ridge at posterior 1/6 of 2nd sternite. A pair of spiniform setal zones on tergum II~VII; in polita, paired zones expanded, fused with each other.

Male A8.

(Fig. 4). A pair of coremata twice as long as pleural lobes; tergite elliptical, with lanceolate caudal end; pleuron expanded posteriorly as lobate; sternite subtriangular, enlarged caudad, posterior margin concave.

Male genitalia.

(Figs 17-30). Uncus linguiform, convex posteriorly, medially fused with tegumen; in four of the seven species, a pair of lateral humps present near apex; socii elongate, extended from ventrobasal area of uncus, with a row of 3-4 spines ventroterminally. Tuba analis with weakly sclerotized area ventrally ('subscaphium'), continuous to gnathos; gnathos as a transverse bulge below tuba analis, with narrow, band-like sclerotization along apical edge. Valva obovate or rectangular, setose on the posterior half of the ventral side, with species-specific groove or projections above basal sacculus. Vinculum narrower to saccus; saccus elongate. Aedeagus straight or bent medially; cornuti absent or as a zone of minute spinules.

Female genitalia.

(Figs 31-35). Papillae anales subtriangular. A pair of hairy humps on the distal margin of S8; interspace between the humps with dense, minute thorns, the thorny area extending above and below S8 humps. Segment S8 entirely or mostly sclerotized, sometimes posterolateral margins forming a semicircular fold (Figs 32 and 35, indicated by asterisk); depending on the species, with a pair of pits (Fig. 35a) or semicircular depression (Fig. 31b) near ostium. Antrum digitate or bowl-shaped, with numerous minute thorns internally; thorny area extending caudally beyond ostium bursae. Ductus seminalis near a connection between ductus and corpus bursae; bulla seminalis as large as (in polita) or smaller than corpus or absent (in costaricae). Corpus bursae very fragile due to its thin wall; signum absent in two species, present in three species and shaped like a dentate keel or a small scobinate disk.

Species diversity.

The distribution of Eucalantica as shown in this paper indicates a high diversity of the genus in the Central America. Three of the five Costa Rican species described in this paper were found in the high-elevation oak forests of Cerro de la Muerte region, indicating that multiple species can coexist in a single ecozone. Interestingly, there exists a different group of congeners in the high mountains of Heredia province. This pattern predicts more undescribed species of Eucalantica present along the montane systems of Costa Rica and other Central American countries.

Key to the adults of Eucalantica species including variants in forewing patterns

Note: External appearance is usually inadequate for species identification of Eucalantica . Whenever possible, examination of the genitalia is advised for reliable identifications of the species.

Key to Eucalantica species based on male genitalia

Key to Eucalantica species based on female genitalia

Note: the females of Eucalantica ehecatlella and Eucalantica pumila are unknown