Amphineurus (Rhamphoneurus) immaculatus, Santos & Santos & Ribeiro, 2022

Santos, Daubian, Santos, Rodrigo dos Reis & Ribeiro, Guilherme Cunha, 2022, Systematics of Amphineurus (Rhamphoneurus Alexander) (Diptera: Tipuloidea: Limoniidae), Arthropod Systematics & amp; Phylogeny 80, pp. 439-494 : 439

3.3.14. Amphineurus (Rhamphoneurus) immaculatus sp. nov.

Material examined.

Holotype: ♂, Chile, Osorno, Pucotrihue [40°32′S 73°42 W], 10/ 12-IV-1968, Peña (USNM)*. Paratypes: 1 ♂, Chile , Osorno , Bahia Mansa [40°35′S 73°44′W], South of Pucotrihue, 12-IV-1968, Peña (USNM) ; 2 ♂, Chile , Chaihuin [39°56′S 73°34′W], 810 m, 20-III-1955, Peña (USNM) . - Additional material: CHILE. 2 ♀ and 1 [sex unknown], Chiloé Is., Chepu [42°2′S 74°1′W], 1/ 3-II-1952, Peña (USNM); 2 [sex unknown], Chiloé Is., Aulen [42°2′S 74°1′W], 8-II-1952, L.P. Guzman (USNM); 1 [sex unknown], Chiloé Is., Chaiten [42°58′S 72°32′W], 5/ 8-II-1954, Peña (USNM); 1 [sex unknown], Chiloé Is., Aucar [42°9′S 73°30′W], 15-I-1952, L.P. Guzman (USNM) .

Etymology.

The word Amphineurus immaculatus is Latin for “unstained”. The term refers to the fact that the wing has no pterostigma or markings.

Diagnosis.

This species is characterized by having sinuous cross-vein m-cu and no markings near R2. Furthermore, the species is characterized by male terminalia with a curved sheath of aedeagus and right mesal lobe similar in shape, but longer than left one, and scutellum rounded in lateral view.

Description.

Wing length 6.22 mm, width 1.74 mm. - Coloration: General coloration brownish-yellow. Rostrum and palpus dark brown. First segments of antenna yellow, remainding segments dark yellow. Head dark brown. Eye black. Thorax brownish yellow, pleura pale. Scutum without stripes. Halter brownish-yellow. Coxae brownish yellow and legs brown. Abdomen blackish brown. - Head (dorsal view Fig. 19B , ventral view Fig. 19A ): Rostrum bifurcated with short appendices; first palpal segment as long as terminal segment; scape as thick as pedicel; terminal flagellomere as long as penultimate. - Thorax (lateral view Fig. 19E , dorsal view Fig. 19F ): Short setae on prescutum. Division line of laterotergite almost vertical; anatergite taller than katatergite. Halter with dilated knob. Wing (Fig. 19D ) without markings; veins near fork of bM (Fig. 19C ) visible; M1+2 as long as M1; R2+3+4 longer than R2+3; wing very light on pigmentation, almost translucent. - Female terminalia (Fig. 19H ): Female tergite IX shorter and as wide as tergite X; cercus slightly curved dorsad. - Male terminalia (Fig. 19G ): Male tergite IX slightly darkened along posterior margin, with deep V-shaped median notch; posterolateral lobes of triangular shape with rounded tips. Ventral branch of gonocoxite expanded in distal tip. Dorsal branch of gonocoxite half-length of ventral branch, curved ventrally. Lobe of gonostylus with rounded lobule; lobule longer than wide, longer than half-length of lobe of gonostylus, wider than stem. Clasper of gonostylus with similarly shaped branches: lateral branch rounded, narrow; medial branch wider, oblong. Mesal lobes of gonocoxite symmetrical; both straight with slightly bent pointed tip. Sheath of aedeagus curved halfway and darkened only near tip.

Remarks.

Some specimens of this new species were previously identified by C.P. Alexander as A. (R.) sanus Alexander, some as A. (R.) nullus Alexander and some as A. (R.) nonnullus Alexander. This species resembles A. (R.) billighami sp. nov. but differs mainly in attachment of m-cu, setae concentration in gonocoxite, shape of male tergite IX and right mesal lobe.

Figures

Figure 19. Amphineurus (Rhamphoneurus) immaculatus sp. nov. A head (ventral view); B head (dorsal view); C detail of wing; D wing; E thorax (lateral view); F thorax (dorsal view); G male tergite IX (dorsal view) and remainder of male terminalia (lateral view); H female terminalia (dorsal view). - Abbreviations: aed sh, sheath of aedeagus; anatg, anatergite; anepm, anepimeron; anepst, anepisternum; aprn, anteropronotum; cer, cercus; cgonst, clasper of gonostylus; cx, coxa; goncx, gonocoxite; hlt, halter; hyp val, hypogynial valve; k, knob of halter; kepm, katepimeron; kepst, katepisternum; ktg, katatergite; l ms, left mesal lobe of gonocoxite; lgonst; lobe of gonostylus; mr, meron; ms lobe, mesal lobe of gonocoxite; mtanepst, metanepisternum; mtepm, metepimeron; mtg, mediotergite; mtkepst, metakatepisternum; mtn, metanotum; p, posterior basalare; patg, paratergite; pprn, postpronotum; presct, prescutum; r ms, right mesal lobe of gonocoxite; sct, scutum; sctl, scutellum; st, sternite; tg, tergite; t 9, male tergite IX.