Leucophora chalten Ramírez-Mora & Patitucci, 2025

Leucophora chalten Ramírez-Mora & Patitucci sp. nov.

https://zoobank.org/NomenclaturalActs/ecef76be-8811-4d15-a4e3-e4922cc2524c

Figs. 14–18 View FIGURE 14 View FIGURE 15 View FIGURE 16 View FIGURE 17 View FIGURE 18

Diagnosis. Leucophora chalten sp. nov. can be differentiated from its congeners by the following combination of characters: abdominal tergites with longitudinal brown vitta and big lateral patches; male with processes of sternite 5 with inward apex, surstylus short, distiphallus tubular, acrophallus short and up-curved and minute free paraphallic processes; female with wide frons, modified ovipositor, only one pair of spiracles, sternite 8 represented by two long and strongly sclerotized parallel plates, cerci (in posterior view) with enlarged and acute lateral distal margin.

Material examined. Holotype 1 ♂ ( MACN): “Arg. Santa Cruz / El Chaltén XII-06 / Mariluis col. [White label, printed]”; “ MACN _En / 36253 [white paper, printed]”; “MR 1314 [white label, handwritten]”; “ Holotype 1♂ / Leucophora / chalten [red label, printed]”.

Paratypes 1 ♀ ( MACN): same as holotype, except: “ MACN _En / 36254 [white label, printed]”; “MR 1315 [white label, handwritten]” ; “ Paratype 1♀ / Leucophora / chalten [red label / printed].

Description

Male ( Figs. 14–16 View FIGURE 14 View FIGURE 15 View FIGURE 16 )

Body length 7.0 mm, wing length 5.5 mm.

Coloration ( Fig. 14 View FIGURE 14 ). Head black with silvery-white pruinosity; frontal vitta black to dark brown with greyish pruinosity ( Figs. 14B, D View FIGURE 14 ). Fronto-orbital plate, parafacialia, genae and face with silvery whitish pruinosity; parafacialia in profile ( Fig. 14C View FIGURE 14 ) with a wide shifting black patch at level of insertion of antennae to level of the postpedicel tip, posteriorly almost reaching the genal patch; genae with a dark brown to black patch from the vibrissal angle to the lower eye margin. Antennae black, inner surface of pedicel, scape and postpedicel with grey and brown pruinosity. Arista dark brown with darker base. Prementum black to dark brown. Palpi brown to light brown basally, darker apically. Thorax black with greyish pruinosity, with three longitudinal dark brown vittae ( Fig. 14D View FIGURE 14 ), central vitta wide, anteriorly filling the space between the presutural acrostichal setae and posteriorly filling the space between almost the dorsocentral setae, extending over the scutellum but less evident, lateral vittae filling the space between the posthumeral and supra-alar presutural setae and intralar postsutural setae and prealar and supra-alar postsutural setae. Anepisternum with an upper anterior brown patch ( Fig. 14A View FIGURE 14 ). Legs dark brown to black, densely covered with grey pruinosity, except the tarsomeres. Pulvilli brownish. Wing membrane hyaline, with a light brown tinge basally. Veins basally brown and darker distally. Calypters yellowish. Halteres brown with darker base. Abdomen dark brown with grey pruinosity, with a longitudinal dark brown vitta ( Fig. 14E View FIGURE 14 ), widened towards posterior of each tergite; with a dark brown posterolateral patch on tergites 3–4 connected with the central vitta at posterior margin. Sternite 5 dark brown with lighter processes. Syntergosternite 7+8, epandrium and cerci black to dark brown, surstylus lighter.

Head. Fronto-orbital plate at narrowest point 1.1x width the anterior ocellus, scarcely widening anteriorly, without setulae; frontal vitta at narrowest point 2x width of anterior ocellus, widening towards lunule; eyes separated at narrowest point 4.2x width of anterior ocellus ( Fig. 14B View FIGURE 14 ). 6–8 pairs of fr s, the uppermost pair very short, with fine short setulae in between ( Fig. 14C View FIGURE 14 ); infr s minute, convergent. oc s pair longer than longest fr s; ocellar triangle with 2 additional pairs of setulae; poc s pair shorter than the oc s. i vt s as long as oc s, convergent; o vt s less than the half the length the i vt s, proclinate. Postpedicel 1.2x the pedicel length; arista 2.5x the postpedicel length, pubescent, longest hairs about 2x the basal diameter of arista. Parafacials 0.4x width of eye. Genae below lowest point of eye margin 0.3x eye height. Vibrissal angle in profile projected beyond level of frontal angle ( Fig. 14C View FIGURE 14 ). Prementum 0.7x head height. Palpus 0.5x as long as head height, slightly expanded at tip.

Thorax. Chaetotaxy: 5 pairs of psut acr s, prescutelar pair longer than the longest presut acr s ( Fig. 14D View FIGURE 14 ). Prealar seta less than half the length the notopleural anterior seta. 5 anepst s. 2+2 kepst s, lower anterior less developed ( Fig. 14A View FIGURE 14 ).

Legs. Fore femur with a row of fine av setulae on basal third. Fore tibia with 1 ad and pv setae. Mid femur with 1 av seta on basal fourth; 5 pv setae on basal half and 1 apical seta; a setae indistinguishable from the surrounding setulae, 1 subapical seta; 2 p setae. Mid tibia with 1 ad and pd setae; 2 p setae. Hind femur with a row of av setae longer on distal half; one complete row of ad setae; 2 subapical d setae; 1 subapical p seta; one row of pv setae on basal half and 2 subapical setae. Hind tibia 3–4 av, ad, and pd setae, 3 p setae.

Abdomen. Lateral marginal setae strong ( Figs. 14A, E View FIGURE 14 ). Sternite 1 3x wider than long, laterally setulose. Sternite 2 slightly longer than wide, posterior margin slightly narrowed, covered with long setulae. Sternites 3–4 slightly wider than long, anterior margin rounded, strongly setulose, longest setae longer than sternite length. Sternite 5 ( Fig. 15A View FIGURE 15 ) 1.3x longer than wide, anteriorly tapered, anterior margin almost straight; processes rather longer than basal region, slender, slightly convergent, apex slightly truncated and with an inner distal projection directed inward, inner margin with long and sinuous setulae, specially basally, outer surface densely covered with strong setae becoming longer distally, longest setae longer than processes length.

Terminalia . Surstylus with slightly curved outer margin, distally tapered and apex rounded ( Fig. 15B View FIGURE 15 ); in profile slightly curved basally, ventral margin slightly sinuous, distally tapered, apex rounded; scattered setulae on ventral surface ( Fig. 15C View FIGURE 15 ). Cercal plate slightly longer than wide, about 0.3x the surstylus length; distally tapered, apex rounded, unpigmented and weakly sclerotized medially; in profile with dorsal surface convex on basal half, acute apex; covered with scattered setulae, 1–2 pairs of long and strong setae apically, longest setae almost 2x the cercal plate length. Pregonite ( Figs. 15E View FIGURE 15 ; 16B View FIGURE 16 ) about 3x longer than wide, more than 0.5x the postgonite length, narrow and slightly constricted at middle, distally acute with 1 basal short seta, without sensilla. Postgonite longer than wide, dorsal margin slightly sinuous, apex narrow and slightly directed ventrally, with 1 seta on ventral surface, with a couple of sensilla basally. Phallapodeme ( Fig. 15D View FIGURE 15 ) in profile basally curved, parallel-sided at middle, strongly expanded towards distal half; epiphallus with rounded apex, slightly constricted preapically and slightly curved ventrally; distiphallus ( Figs. 15D View FIGURE 15 ; 16A View FIGURE 16 ) slightly curved on basal half, shorter than phallapodeme, with very short and slender free paraphallic processes with a trident-shaped tip ( Fig. 16C View FIGURE 16 ); acrophallus unpigmented and up-curved distally ( Fig. 16C View FIGURE 16 ).

Female ( Figs. 17–18 View FIGURE 17 View FIGURE 18 )

Body length 6.2 mm, wing length 5.0 mm.

Differs from male as follows:

Coloration ( Fig. 17 View FIGURE 17 ). Fronto-orbital plate on inner half and ocellar triangle with golden pruinosity ( Fig. 17B View FIGURE 17 ).

Head. Fronto-orbital plate at narrowest point 3x width of anterior ocellus; frontal vitta at narrowest point 4.5x width of anterior ocellus, parallel sided; eyes separated at narrowest point slightly more than 10x width of anterior ocellus ( Figs. 17B, D View FIGURE 17 ). 6 pairs of fr s ( Fig. 17C View FIGURE 17 ). oc s as long as the longest fr s. i vt s longer than oc s; o vt s proclinate and slightly divergent. Postpedicel 1.4x the pedicel length; arista 2.3x the postpedicel length. Prementum 0.8x head height.

Legs. Mid femur with 4–5 pv setae on basal half, with a row of a setae on basal half and 1 subapical seta; 2 p setae. Hind femur with 1 pv seta on basal fourth and 1 subapical seta.

Abdomen. Sternite 1 3x wider than long, with a couple of lateral setae. Sternites 2–5 1.5–1.8x longer than wide, setulose with long setae on posterolateral margins. Sternites 4–5 narrowed anteriorly.

Ovipositor ( Fig. 18 View FIGURE 18 ). Tergite 6 represented by a pair of well sclerotized lateral plates, slightly longer than wide, posterior margin narrow towards middle, anterior margin narrowed and rounded ( Fig. 18A View FIGURE 18 ); in profile with anterior half of dorsal surface straight ( Fig. 18C View FIGURE 18 ), slightly convex on posterior half, narrowed ventrally; posterior margin with a row of few but strong and long setae which extends onto the lateroventral membranes forming with setulae of the sternite 6 a more or less continuous band around segment (longest setae longer than tergite length). Spiracle 6th situated in membrane at middle length of tergite ( Fig. 18B View FIGURE 18 ). Tergite 7 similar in shape as tergite 6 but 2x longer than wide, longer than tergite 6, posterior margin slightly concave; in lateral view wide and slightly rounded ventrally; posterior margin unpigmented, setation as tergite 6 but longest setae shorter than tergite length. Spiracle 7th not observed/absent. Tergite 8 narrowly divided into a pair of robust and stoutest plates, slightly more than 2x longer than wide, in dorsal view strongly tapered anteriorly, on posterior half widened and almost touching on middle, outer margin strongly curved; in profile ( Fig. 18C View FIGURE 18 ), anterior margin acute, posterior half curved and rounded; posterior margin setulose. When fully extended, anterior region of tergites 6–8 remain hidden in the anterior segment ( Figs. 18A, C View FIGURE 18 ). Epiproct rhomboid ( Fig. 18A View FIGURE 18 ), curved ventrally ( Fig. 18D View FIGURE 18 ), setulose on posterior half. Sternite 6 slightly longer than wide, anterior margin slightly truncated and well sclerotized, posterior half weakly unpigmented; posterior margin setulose ( Fig. 18B View FIGURE 18 ). Sternite 7 about 1.2x longer than wide, slightly longer than sternite 6, anterior margin tapered and rounded, posterior margin unpigmented and setulose; membrane towards posterolateral corners of sternite weakly sclerotized. Sternite 8 represented by two longitudinal, narrow, long, and well sclerotized lateral plates, almost touching at anterior and posterior margin, without setulae, only with very short microtrichia; the membrane outer to the plates weakly sclerotized. Hypoproct wider than long, anterior margin rounded, posterior margin with short setulae; due the shape modification of segment 8, the hypoproct is transverse in position. Cerci modified as flat, strongly sclerotized and unmovable pair of transverse plates ( Figs. 18A–C View FIGURE 18 ); in posterior view ( Fig. 18D View FIGURE 18 ) with acute lateral projection directed ventrally, dorsal margin slightly rounded, on middle towards inner margin with an up-curved projection with a fringe of 4–6 strong but short spinules, more evident in profile; in profile ( Fig. 18C View FIGURE 18 ), the ventral projection with irregular anterior margin; with some microtrichia on ventral surface. Spermathecae longer than wide ( Fig. 18E View FIGURE 18 ).

Remarks. In external appearance, L. chalten sp. nov., resembles those in L. plumiseta , however can easily differentiated by the arista pubescent. The pregonite shaped and the up-curved acrophallus in L. chalten sp. nov., are similar to those in L. catamarca sp. nov., and L. junin sp. nov., but differ from both in having a bare pregonite ( Fig. 16B View FIGURE 16 ). From L. catamarca sp. nov., also differs by the slender and very short free paraphallic processes ( Fig. 16C View FIGURE 16 ) and by the tubular and straight distiphallus. Differs from L. junin sp. nov., by the relatively longer distiphallus, the presence of the short free paraphallic processes and the absence of distal cuticular projections of the acrophallus. Female ovipositor of L. chalten sp. nov., share modifications of tergite 8, epiproct, cerci and the presence of only 1 pair of spiracles (spiracles 6th) with C. catamarca sp. nov., but differs by the shape of cerci, epiproct, hypoproct and sternite 8.

Etymology. The species’ epithet refers to the municipality of “El Chaltén”, where the holotype was collected. This municipality is located within the National Park “Los Glaciares”.

Distribution. Neotropical: ARGENTINA (Santa Cruz) ( Fig. 53D View FIGURE 53 ).