Rasahus deliquus, Swanson, 2018

Swanson, Daniel R., 2018, Three new species of Rasahus, with clarifications on the identities of three other Neotropical corsairs (Heteroptera: Reduviidae: Peiratinae), Zootaxa 4471 (3), pp. 446-472 : 451-452

Rasahus deliquus sp. nov.

( Fig. 2 )

Diagnosis: Easily separated from all other species of Rasahus by the combination of lacking any major pale maculae in the apical half of the hemelytral membrane, particularly in or posteriad of the medial cell, the nearly completely luteous margin of the connexiva. The external genitalia of the male also are unique in possessing the combination of a moderately-slender, weakly-bent median process of the pygophore and two subequally-deeplylobed parameres.

Coloration: Generally dark castaneous, except base and apex of clavus, corium adjacent to clavus, very faint transverse suffusion in cubital cell of membrane, small spot on hemelytra membrane adjacent to corial apex, basal fourth to third of mesofemur, basal half of metafemur, all tarsi, and all connexiva dorsally and ventrally (except small fuscous spot at mesoposterior corner) pale. Posterior pronotal lobe slightly darker than anterior lobe. Hemelytra blackish, darker than body (except for pale spots). Ventrites 3–7 distinctly tawny, with area around spiracles and sublateral area faintly suffused with fuscous. Ventral surface of connexiva luteous and distinctly contrasting tawny ventrites.

Structure: Anteocular region covered with short golden pile, laterally with few long dark setae. Interocular region with width much narrower than width of eye, more or less glabrous. Neck generally glabrous.

Antennae: as per description under Rasahus .

Eyes in lateral view surpassing dorsal margin and reaching ventral margin.

Ocelli large, raised, separated from each other by width or slightly less of one ocellus and from eye by halfwidth of one ocellus.

Rostrum: as per description under Rasahus .

Pronotum: Anterior pronotal lobe with sulci and granules within sulci distinct, sparse long setae in remains of sulci. Posterior pronotal lobe with small longitudinal wrinkles coming from transverse pronotal suture, otherwise smooth, not granulose or rugulose, pilose along lateral and posterior margins.

Scutellum with apex prolonged in apically-rounded spine.

Pleura: Propleuron with integument sparsely granulate, delimited laterally from dorsal face by distinct carina. Mesopleuron with integument generally smooth, slightly punctate, with dense patch of pile near ventral margin. Metapleuron with integument transversely wrinkled and granulate, glabrous, metapleural sulcus narrow between carinae.

Sterna: Mesosternum damaged by pin. Metasternum convex medially, granulate, slightly carinate posteriorly.

Hemelytra distinctly exceeding abdominal apex, appearing glabrous, membranal cells minutely wrinkled.

Forelegs: Profemur with ventral setae multiseriate. Protibia slightly expanded at apex, protibial fossula spongiosa long, greater than half-length of tibia.

Middle legs: Mesotibial fossula spongiosa long, covering slightly less than one-half of tibia. All else as forelegs.

Hind legs: Femur and tibia with dense short pile near apex. All else as middle legs.

Abdomen with anterior portion of third ventrite also carinate medially.

Male genitalia: Eighth ventrite extended caudad as median triangular spine. Pygophore sparsely pilose, posterior margin somewhat concave between median process and base of parameres, median apical process tall, moderately slender, slightly bent. Parameres large, asymmetrical, both generally spade-shaped and deeply lobate, moderately pilose, right paramere with median lobe acutely triangular, apex rounded and bent inward, left paramere with median lobe more rounded, apex broadly rounded. Aedeagus not examined.

Female: unknown.

Measurements (in mm): total length (apex of head to apex of hemelytra): 18.2; head length: 2.8; head width (across eyes): 2.0; anteocular length: 1.4; postocular length: 0.3; neck length: 0.2; scape length: 1.8; pedicel length: 4.1; basiflagellum length: 2.8; distiflagellum length: 3.0; antennal segmental ratio: 1.0: 2.25: 1.5: 1.7; eye length: 1.1; eye width: 0.7; rostral segment 1 length: 0.9; rostral segment 2 length: 1.9; rostral segment 3 length: 0.9; rostral segment ratio: 1: 2: 1; prothorax length: 3.9; prothorax width (across humeri): 4.2; anterior pronotal lobe length: 2.4; posterior pronotal lobe length: 1.5; scutellum length: 2.3; scutellum width (at base): 1.8; hemelytra length: 12.9; procoxa length: 2.1; protrochanter length: 1.1; profemur length: 4.3; protibia length: 3.6; protibial fossula spongiosa length: 2.6 (of which 0.5 extends beyond apex of protibia); protarsi length: 1.8; protarsal segment ratio: approximately: 1.0: 1.7: 2.4; mesocoxa length: 1.1; mesotrochanter length: 1.1; mesofemur length: 4.4; mesotibia length: 3.8; mesotibial fossula spongiosa length: 1.6; mesotarsi length: 2.1; mesotarsal segment ratio: approximately 1.0: 2.1: 2.3; metacoxa length: 1.2; metatrochanter length: 1.2; metafemur length: 7.0; metatibia length: 7.3; metatarsi length: 2.8; metatarsal segment ratio: approximately 1.0: 2.5: 2.5; abdomen length: 8.6; abdomen (widest) width: 5.1; pygophore length: 1.6; pygophore width (across widest point): 1.6.

Material examined: PANAMA: Chiriqui Prov., Progreso, 16 April 1923, “390”, F. M. Gaige [1 male, holotype] ( UMMZ) .

Distribution: Known only from the type locality ( Fig. 4 ).

Etymology: The specific epithet comes from the Latin adjective deliquus , - a, - um, ‘wanting, lacking’ and references the absence of any pale macula in the medial membranal cell.

Remarks: The species is closest in coloration to those species lacking any pale maculae in or behind the medial cell of the hemelytral membrane, i.e., R. atratus and R. guttatipennis . Both differ from R. deliquus sp. nov. in lacking completely luteous margins of the connexiva. From the former, R. deliquus sp. nov. is easily separated by the presence of a distinct postscutellar macula (hemelytra wholly black in R. atratus ); it is also slightly larger (16.6 vs. 18.2 mm) as well as geographically separated ( Brazil, Peru vs. Panama). From the latter, R. deliquus sp. nov. may be separated by the absence of the pale macula of the cubital cell in the hemelytral membrane, as well as the larger size. The holotype possesses a distinctly dark-reddish cast to the head, pronotum, and dark portions of the legs; however, it is unknown whether this represents a real characteristic of the color pattern or is simply a result of differential melanization of the cuticle. Based on Coscarόn’s (1983a) plates, the genitalia, although generally similar to congeners, appear to be unique within the genus in possessing the combination of a moderately-slender, weakly-bent median process of the pygophore ( Fig. 5A ) and two subequally-deeply-lobed parameres ( Fig. 5B, C ).

Figures

FIGURE 2. Rasahus deliquus sp. nov., adult male (holotype): (A) dorsal habitus; (B) lateral habitus; (C) pronotum, dorsal view; (D) pygophore, caudal view; (E) labels. Scale bar = 2 mm.

FIGURE 4. Map indicating type locality of Rasahus nesiotes sp. nov., R. deliquus sp. nov., and R. abolitus sp. nov.

FIGURE 5. Male external genitalia: (A–C) Rasahus deliquus sp. nov.: (A) median process of pygophore; (B) left paramere; (C) right paramere; (D–F) R. abolitus sp. nov.: (D) median process of pygophore; (E) left paramere; (F) right paramere; (G–I) R. myrmecinus stat. rev. et comb. nov.: (G) median process of pygophore; (H) left paramere; (I) right paramere.