Paragini, with the single genus Paragus, is a compact and distinctive group occurring in all continents other than South America and Antarctica. Paragus species are small, slender to moderately robust, with thorax black or with apex of scutellum pale, and abdomen usually extensively red-orange to entirely black. Paragus has postpronotum bare, antenna short, anterior anepisternum bare, abdomen parallel-side, face yellow in background colour, metaepisternum bare, scutum black laterally, at most with a poorly defined yellow polinose vitta, and metasternum bare.
The subgenus Afroparagus sensu Vujic et al. (2008) has eyes with vittae of shorter pile; face with distinct facial tubercle; scutum without polinose, submedian vittae; scutellum without conspicuous teeth on posterior margin, rhomboidal; wing hyaline with extremely reduced microtrichia; spurious vein ending before meeting point of vein M1 with vein DM; abdomen very short and rounded; terga 1–5 completely fused, at least laterally; the posterior margins of terga 3 (female) and tergite 4 (in both sexes) visible except laterally; male genitalia: postgonite curved anterior and posteriorly; ejaculatory apodeme with three apical ridges; minis large, lateral arms of minis short; epandrium in narrower part half the length of cercus; lateral lobe of aedeagus not fused with aedeagal apodeme; aedeagal apodeme with dorsal structure extremely developed, with spines and reduced lateral arms; aedeagus in lateral view slightly asymmetrical, ‘amphora-like’.
Paragus (Afroparagus) borbonicus Macquart, 1842.
Macquart, P.J.M. 1842. Dipteres exotiques nouveaux ou peu connus. Tome deuxieme.--2e partie. Mem. Soc. R. Sci. Agric. Arts, Lille 1841(1): 65-200, 22 pls. [1842.??.??]
Synonyms:
Paragus borbonicus Macquart, 1842: 166.
Paragus latus Walker, 1849: 545.
Paragus antimenes Walker, 1849: 546.
Paragus nudipennis Loew, 1858: 376.
Paragus latecinctus Bigot, 1884: 540.
New description:
MALE.
Head: Face with facial tubercle, yellow, black ventroalterally on epistoma and gena, long whitish-yellow pilose; frontal triangle yellow with a medial dark brown joining facial vitta ventrally, whitish-yellow pilose; vertical triangle black, black pilose, golden pollinose anteriorly; eye pilose; antenna black, basoflagellomere brown, slightly elongate-oval; arista brown, submedial; occiput black, silver pollinose, withe pilose ventrally, golden pilose dorsally.
Thorax: Scutum shiny black, long golden pilose with appressed pile anteriorly; postpronotum bare; scutellum shiny black, long golden pilose, subscutellar fringe complete. Pleuron black, with long golden pile, very dense on posterior anepisternum, golden pollinose medially and dorsally; metasternum bare; calypter yellow; plumula yellow; halter yellow; spiracular fringes yellow. Wing: Wing membrane hyaline, mostly bare with scarce microtrichia medially and apically. Legs: Entirely yellow except coxae and trochanter black; profemur black on basal 1/3, mesofemur black on basal 1/2 and metafemur black except apical 1/4 yellow; yellow pilose with long pile on tibiae, especially metatibia.
Abdomen: Parallel-sided, concave, punctuate, yellow pilose. Terga 1-2 black; terga 3-6 orange, with some darker areas on tergum 4; terga 1–5 completely fused, at least laterally; the posterior margins of terga 3 (female) and tergite 4 (in both sexes) visible except laterally.
FEMALE.
Similar to male except as follows: face yellow with medial narrow black fascia, black ventrolaterally; frons black, yellow pilose; abdomen black with a broad arcuate orange fascia between terga 2 and 3.
Paragus is the only genus of the tribe Paragini and its phylogenetic position is uncertain. Dusek and
Laska (1967) did not comment on the sister group of Paragus but mentioned that the genera Didea and Paragus share some characters of the adult morphology and male genitalia and they placed Paragini as one of the first branches of Syrphinae, commonly called basal clades. Shatalkin (1975) said that Paragini was a tribe aberrant in relation to all other tribes of the subfamily based on characters of the male genitalia. Rotheray and Gilbert (1989) using larval characters, resolved the genus as sister group of the tribe Pipizini. In 1999, Rotheray and Gilbert reported Paragus as sister group of the clade Eupeodes + Scaeva + Ischiodon.
Ståhls et al. (2003) using morphological and molecular characters resolved Paragus as sister group of the genera Chrysotoxum and Syrphus. Hippa and Ståhls (2005), based only on adult morphological cahracters, found a similar conclusion: Paragus as sister group of Chrysotoxum, Syrphus, Toxomerus and Sphaerophoria. Mengual et al. (2008) using only molecules, resolved Paragini as sister group of Allobaccha, a position never suggested before.
Although there are recent studies about the intrageneric classification of Paragus (Kassebeer, 1999a,b, 2001; Rojo et al., 2006; Vujic et al., 2008), the placement of this tribe in the subfamily Syrphinae is unresolved as previous results disagree. Currently there are four subgenera based on the study by Vujic et al. (2008): Paragus s. str., Serratoparagus, Afroparagus and Pandasyopthalmus (the latest with two species groups, tibialis and jozanus groups).
unless otherwise stated