Alavesia longicornuta Sinclair & Grimaldi 2020, new species
Creators: name: Sinclair, Bradley J.
name: Grimaldi, David A.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Atelestidae
Alavesia
Alavesia longicornuta

description: Alavesia longicornuta, new species   Figures 1G, 2F, 5A, 8F, 9C–D, 13D, 14A  
 DIAGNOSIS: Males of this species are distinctive, characterized by greatly lengthened aristalike stylus (figs. 13D, 14A) (2.9 × length of postpedicel), bearing a light, apical flaglike expansion; elongate and flattened palpi; CuA strongly recurved, in line with m-cu; CuA+CuP sharply curved subapically to wing margin. Distinguished from males of A. longistylata by slightly longer stylus with a light (vs. dark) apical “flag,” broader palpus, longer and narrower wing; cell cua significantly thicker.   
 DESCRIPTION: Male. Coloration, except stylus, not preserved. Head: Scape and pedicel quadrate, scape longer than pedicel. Postpedicel greatly lengthened, L/ W 4.0, tapered on apical two-thirds, longer than head height. Stylus with two small basal articles, with apical aristalike stylus 2.9 × length of postpedicel (fig. 1G); apex of stylus with light, oval, flaglike flattened expansion (fig. 8F). Palpus bladelike (fig. 9C, D), flattened, projecting, strongly tapered, with fine setae ventrally, length about subequal to eye height.   
 Thorax: Chaetotaxy thickened (fig. 5A): biserial row of short acrostichal setae; dorsocentral setae similar to acrostichals, ending in pair of long prescutellar dorsocentral setae; 2 anterior and 1 posterior postpronotal setae; 4 anterior notopleural setae of variable lengths, 1 posterior notopleural seta; 1 postsutural supraalar seta; 1 postalar seta; 2–3 pairs of scutellar setae.   
 Legs: Forecoxa with short erect anterior setae. Femora with anteroventral row of short setae. Tibiae with long, apical ventral seta. Hind tibia with dorsal row of setae, length about half width of tibia; posterior face clothed with brush of fine setae.   
 Wing: Length 2.2 mm (fig. 2F), costa terminating slightly beyond M 1+2; Sc nearly reaching costal margin; R 4+5 parallel to M 1+2 until near wing margin; crossvein r-m opposite near middle of cell dm; apex of M 4 at equal distance between M 1+2 and CuA+CuP; CuA straight, turned toward wing base, aligned with bm-m; apex of cell cua truncate, length of cell cua shorter than cell bm; CuA+CuP mostly straight, sharply curved subapically to wing margin.   
 Abdomen: Setae short, without distinct posteromarginal setae. Segments 1–5 broad, remaining segments retracted with segment 5. Terminalia obscured by bubble.   
TYPE MATERIAL: Holotype, male, JZC Bu-556 (AMNH). Paratype: USNM PAL 726871 (1 male, USNM).  
 ETYMOLOGY: The specific epithet is from the Latin cornutus (“horned, bearing horns”), in reference to the elongate aristalike stylus.
description: Published as part of Sinclair, Bradley J. & Grimaldi, David A., 2020, Cretaceous diversity of the relict genus Alavesia Waters and Arillo (Diptera: Empidoidea: Atelestidae), pp. 1-40 in American Museum Novitates 2020 (3961) on pages 17-25, DOI: 10.1206/3961.1, http://zenodo.org/record/5370399