Dorachosa bilabeculafissura, Sanborn, 2024

Dorachosa bilabeculafissura sp. nov. ( Figs. 3–4 View Figure 3 View Figure 4 )

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Type material: Holotype. “ Vassoures – RJ / I–1965 / Murilo ” ♂ ( DZRJ).

Etymology. The name is a combination of bi - (L., bi -, two), - labecula - (L., labecula, diminutive, spot, stain, blemish), and - fissura (L., fissura, crack, fissure) in reference to the two small spots on either side of the dorsal midline in the ambient fissure of the pronotum.

Remarks. This is one of a small number of species in the genus that possess large male opercula. The coloration patterns and basal lobe appendages distinguish all species from one another.

Diagnosis. Dorachosa bilabeculafissura sp. nov. is one of a small proportion of species in the genus that possess large male opercula. Once again, the shapes of the claspers and pygofer basal lobe appendages quickly distinguish the species within the genus. The presence of mesothoracic and postclypeal markings distinguish Dorachosa cephalodigramma (Sanborn 2020b) and Dorachosa polygramma (Sanborn 2020b) from the new species. The complete lack of dorsal markings and equally sized extensions of the basal pygofer lobe distinguish Dorachosa chelappendicula (Sanborn 2020c) from the new species. Similarly, there is a lack of dorsal markings and the basal lobe appendage has a leaf-like terminus with three points in Dorachosa phyllodes (Sanborn 2019a) . Dorachosa melanomesocranon (Sanborn 2019a) can be distinguished by its primarily piceous head and lack of pronotal markings, and a basal lobe appendage that is flattened, forms a right angle, and tapers distally to a point. Finally, Dorachosa quadroacuminata (Sanborn, 2020d) is most similar to the new species but there is a single spot on the dorsal midline in the pronotal collar ambient fissure instead of the small spots on either side of the midline, the fore wings are about 3.0 times longer than broad rather than the 2.38 times, and the basal lobe appendages have four extensions rather than the two as found in the new species.

Description.

Ground color ochraceous, with limited castaneous and piceous markings. Live or fresh specimens are probably green.

Head. Head slightly wider than mesonotum, ground color, lateral vertex between eye and lateral ocelli and anterolaterally light castaneous, supra-antennal plates light castaneous, castaneous spots in anterior and posterior cranial depressions, piceous vertex margin along posterior half of dorsal eye. Ocelli rosaceous, fading to ochraceous in two ocelli. Eyes dark castaneous. Dorsal head with short silvery pile, longer and denser silvery pile posterior to eye. Ventral head ground color except piceous posterior two thirds of lorum. Postclypeus centrally sulcate from anterior to posteroventral margin to around apex, with eleven transverse ridges, short silvery pile on lateral margin and in lateral transverse grooves.Anteclypeus ground color. Ventral head and anteclypeus covered with short silvery pile, longer pile posteroventral to eye and radiating from lorum. Mentum ground color, labium ground color with castaneous lateral fascia becoming piceous distally and castaneous tip, reaching to anterior hind coxae. Scape and proximal pedicel ground color, distal pedicel castaneous, flagellar segments missing but probably castaneous.

Thorax. Dorsal thorax ground color, castaneous marks in posterior paramedian fissure, anterior lateral fissure, a small spot on either side of dorsal midline in ambient fissure. Pronotal collar ground color with castaneous spot anterior to pronotal collar lateral angle. Mesothorax ground color with castaneous fascia along parapsidal suture not reaching anterior margin, scutal depressions castaneous, piceous spot on lateral mesonotum in anterior wing groove. Silvery pile on posterior mesothorax, between arms of cruciform elevation, radiating from posterior wing groove, and on posterior metanotum margin. Ventral thoracic segments ground color with castaneous fascia along lateral junctions of coxae and ventral thoracic segments, covered with short silvery pile.

Wings. Fore wings and hindwings hyaline, lightly bronzed distally, with eight and six apical cells respectively. Venation ground color but darkening in apical cells, castaneous spot at base of costa and castaneous proximal and distal anal vein 2 + 3. Basal membrane grayish, darker along anal vein 2 + 3, light infuscation on wing margin along apical cells. Hindwing venation ground color at base becoming darker in apical cells, median vein darker, castaneous spot on base of anal vein 2 extending across base of anal vein 3. Anal cell 3 gray with castaneous distal spot and posterior margin, anal cell 2 along anal vein 3 and anal vein 2, anal cell 1 along anal vein 2 margined with gray.

Legs. Ground color except castaneous marks on lateral coxae, light castaneous distal tarsi, and castaneous distal pretarsal claws, short silvery pile on coxae, long golden pile radiating from legs. Fore femora with proximal spine longest and most angled, secondary spine almost upright, of intermediate length, tertiary spine angled greater than and not quite as long as secondary spine, secondary and tertiary spines with curving tip, very small apical spine extending from distal tertiary spine base, spines castaneous. Tibial spurs and tibial combs ground color with castaneous tips. Meracanthus ground color, broadly triangular, reaching beyond anteromedial opercular margin.

Opercula. Male operculum large for the genus, ochraceous covered with short silvery pile and radiating longer pile, small, rectangular lateral extension near lateral base, anterolateral margin straight, angled, curved laterally to rounded posterior margin forming a roughly semicircular posterior, rounded medial margin, opercula not meeting medially, concave anteromedial margin to base, covering all but posterior tympanal cavity, reaching to anterior margin of sternite II.

Abdomen. Abdominal tergites ground color, castaneous spot in lateral timbal cavity, on lateral tergite 2, tergites 3–8 with castaneous posterior margins and lateral castaneous spots, castaneous reducing in posterior tergites, tergites covered with short golden pile, long silvery pile radiating from lateral tergites 4–8. Timbal completely exposed, timbal with ten long ribs and nine intercalary ribs. Male sternites I ground color, sternite II ground color with transverse castaneous fascia across midline, sternite III ground color with transverse castaneous fascia on anterior midline, longitudinal castaneous mark on anterior half of midline, sternites IV–V ground color, sternites VI–VII ground color with castaneous spot on anterior midline, auditory capsule ground color with castaneous spot, sternite VIII with transverse posterior margin, open V-shape when viewed from posterior, epipleurites ground color, castaneous laterally in epipleurites 6–7, sternites and epipleurites covered with short silvery pile, denser along groove between sternites and epipleurites, and radiating long golden pile.

Genitalia. Male pygofer ground color with light castaneous dorsal midline, covered with short silvery pile. Dorsal beak narrow, curving ventrally then straightening out from base, longer than piceous anal styles. Pygofer upper lobe small, folded medially. Pygofer basal lobe extended, swollen, adpressed to pygofer, curving mediad, ground color with piceous spot on distomedial corner, dense, radiating long golden pile. Uncus absent, claspers expanding along sides of and barely meeting posterior to anal styles, claspers diverge at an approximate right angle to acutely angled distolateral corner. Basal lobe appendage flattened, broad at base, angled laterad, recurving, extension forms an asymmetrical, claw-like terminus with proximal extension small and distal extension very long and curved. Aedeagus castaneous, tubular with a pair of terminal extensions.

Female is unknown.

Measurements (mm). Length of body: 16.90; length of fore wing: 20.80; width of fore wing: 8.75; length of head: 3.00; width of head including eyes: 5.75; width of pronotum including suprahumeral plates: 6.75; width of mesonotum: 5.50.

Distribution. The new species is known only from the holotype specimen collected at Vassoures (22°24’14”S, 43°39’46”W) in the state of Rio de Janeiro, Brazil.