Allodia paleoafricana, Bouju & Rosse-Guillevic & Griffon & Bojarski & Szwedo & Perrichot, 2021

Bouju, Valentine, Rosse-Guillevic, Simon, Griffon, Marion, Bojarski, Błażej, Szwedo, Jacek & Perrichot, Vincent, 2021, The genus Allodia (Diptera: Mycetophilidae) in Miocene Ethiopian amber, Fossil Record 24 (2), pp. 339-346 : 340-343

Allodia paleoafricana sp. nov.

LSID (species) urn:lsid:zoobank.org:act:D4BB6391-7842-4F9F-9420-F083136A255C

( Figs. 1–3 )

V. Bouju et al.: The genus Allodia ( Diptera : Mycetophilidae ) in Miocene Ethiopian amber 341

Material

Holotype MAIG 6017 , a complete female specimen preserved in a piece of clear amber (4.3 × 3.2 × 2.2 cm) from a locality near Weldiya in the South Wollo Zone, Amhara Region, Ethiopia.

Diagnosis (female)

Scutum with strong anteromarginal setae, lateral prealar and postalar setae, and dorsocentral setae. Scutellum with two strong posterior setae. Antepronotum with three to four strong setae. Wing with stem of M-fork slightly shorter than r–m, base of M4–CuA fork nearly aligned with base of r– m, CuP fading only shortly before M4–CuA fork. Metacoxa with one posterobasal and one posterodistal bristle.

Description

Head. Longer than broad, 0.54 mm long and 0.32 mm wide. Eyes widely separated, subcircular, about half as long as head, maximal diameter 0.27 mm ( Fig. 2a ). Three ocelli present, median ocellus larger than laterals, lateral ocelli touching eye margin. Antennae inserted near head’s midlength, 1.25 times as long as thorax ( Fig. 1 ); scape and pedicel subequal in size, 0.07 mm long, with gradual basal constriction, with few apical setae; flagellum progressively narrowed towards tip, 0.97 mm long, with 14 cylindrical articles clothed with fine trichia; first flagellomere longest, 1.6 times as long as scape, following flagellomeres all longer than wide, approximately as long as scape. Head covered with fine trichia, except for row of about five short setae near eye margin, above lateral ocellus ( Fig. 2a ).

Thorax. Antepronotum with three to four strong setae, other lateral sclerites bare ( Fig. 2a ). Mesonotum 0.90 mm long, 0.62 mm wide; scutum coated with thin, small, decumbent setae; additionally, with rows of long, erect setae: one anteromarginal, one to two laterals (prealar and postalar, more numerous around wing base), and two dorsocentrals ( Fig. 2a–c ); scutellum with two very long, posterior setae; several of these strong, dark thoracic setae detached from the specimen and floating around in amber matrix, although their points of insertion clearly visible, forming small, shallow pits on integument; setal apex apparently simply pointy.

Legs. All legs slender, pubescent; the tibiae covered by regular rows of trichia. Metacoxa with one anterodorsal bristle and one posterodorsal bristle ( Fig. 2a ). Profemur 0.90 mm long, 0.11 mm wide, thinner than others; metafemur 1.37 mm long, 0.20 mm wide; mesofemur 1.17 mm long, 0.12 mm wide. Protibia 1.09 mm long, 0.09 mm wide; mesotibia 1.15 mm long, 0.09 mm wide, with three to four anterodorsal bristles and one posterodorsal bristle; metatibia 1.56 mm long, 0.15 mm wide, with 13–14 dorsal bristles; tibial spur formula 1–2–2, longest metatibial spur about onethird of tibial length; tarsi slender, length of protarsomeres (in mm): TI 1.25, TII 0.75, TIII 0.52, TIV 0.30, TV 0.26.

Wings ( Fig. 3 ). Wings 2.66 mm long, ca. 1.00 mm wide, with microtrichia arranged on membrane. Sc short, approximating but not ending in R; R1 reaching C on the apical wing quarter; R2+3 absent; C reaching apex of R4+5, both veins reaching margin before wing apex; r–m slightly longer than stem of M-fork (M1–M2); M-fork situated distally of M4– CuA fork. CuP short, fading before reaching wing margin, ending around level of M4–CuA fork. A1 weak, less distinct than other veins, thus ending unsure.

Abdomen. About as long as wings, narrowly joined to thorax, densely pubescent, with six distinct segments. Terminalia mostly invisible in profile view, partly concealed by left metatibia and pubescence; only a small, apically rounded part of cerci visible ( Fig. 2d ).

V. Bouju et al.: The genus Allodia ( Diptera : Mycetophilidae ) in Miocene Ethiopian amber 343

Etymology

The specific epithet combines palaiós (Greek, meaning “ancient”) with Africa, in reference to the origin of the amber piece. The specific epithet is to be treated as an adjective in a genitive case.

Figures

Figure 1. Allodia paleoafricana sp. nov., female, holotype MAIG 6017. Habitus in lateral view.

Figure 2. Allodia paleoafricana sp. nov., female, holotype MAIG 6017. (a) Details of head and thorax in lateral view, with indication of mesonotal setae. (b) Thorax in dorsal view, highlighting the lateral and posterior mesonotal setae. (c) Mesonotum in dorsal view, highlighting the rows of dorsocentral setae. (d) Abdomen in profile view. Abbreviations: am s, anteromarginal setae; crc, cerci; dc s, dorsocentral setae; postal s, postalar setae; psctl s, posterior scutellar setae; preal s, prealar setae.

Figure 3. Wing of Allodia paleoafricana sp. nov., female, holotype MAIG 6017. (a) Photograph of left wing. (b) Drawing with indication of venation.