Epimesoplecia stana, Lin, Xiuqin, Shih, Chungkun & Ren, Dong, 2015

Lin, Xiuqin, Shih, Chungkun & Ren, Dong, 2015, Revision of the genus Epimesoplecia Zhang, 2007 (Diptera, Nematocera, Protopleciidae) with five new species, ZooKeys 492, pp. 123-143 : 129

Taxon classification Animalia Diptera Protopleciidae

Epimesoplecia stana sp. n. Fig. 6

Etymology.

The epithet is an arbitrary combination of letters used as a nun in apposition.

Diagnosis.

Antennae moniliform. Sc very close to the level of r-m; fork of Rs distad of fork of M1+2; R2+3 distad of crossvein r-m; R2+3, straight, distinctly less than bRs and dRs combined; bRs 2.5 times as long as dRs, the latter 2 times as long as r-m; bM1+2 significantly longer than dM1+2 (2.3 times); bM3+4 slightly longer than m-cu; cell bp narrower than cell ba terminally.

Material.

Holotype: female, NO. CNU-DIP-NN-2013201p/c, in lateral view, a well-preserved body with partial antennae, almost complete wings and legs.

Horizon and locality.

The specimen was collected from the Jiulongshan Formation, late Middle Jurassic age (Late Callovian) from Daohugou Village, Ningcheng County, Inner Mongolia Autonomous Region in China.

Description.

Head (Fig. 6C): small, in lateral view; Antennae with segments 1-11 visible as preserved, moniliform. Maxillary palpi barely visible.

Thorax (Fig. 6A, B): Prothorax barely visible; scutum of mesothorax broad and oval, convex obviously; scutellum of metathorax projecting, semicircular; haltere depressed.

Legs (Fig. 6A, B): Forelegs relatively slender, femur slightly expanded, slightly shorter than tibia; tarsi not preserved. Mid legs similar to forelegs, femur thicker than tibia; tibial spurs minute; tarsi not preserved. Hind legs: femur slightly expanded, slightly shorter than tibia; tibia slender and long as preserved.

Wings (Fig. 6F): Wing long and narrow, more than 3 times as long as width (length: 11.2 mm, width: 3.4 mm as preserved); apex of wings covering the abdominal terminalia. Costal field long and thin, Sc reaching C very close to the position of r-m; Rs arising from basal one-fourth of wing length, furcating distad to level of fork of M1+2. Stem of Rs longer than stem of R, the former longer than R2+3, bRs 5 times as long as r-m; crossvein r-m longer than m-cu; CuA slightly curved, ending at posterior margin; vein A1 short, slightly longer than half of cell bp.

Female genitalia (Fig. 6D): The 8th segment slightly smaller than preceding segments, genitalia simple, cerci segments not visible.

Dimensions

(in mm). Holotype: female, CNU-DIP-NN2013201p/c, Body length 10.2, maximal width of body 2.2. Antennae 1.1 (segments 1-11). Foreleg: femur 2.5; tibia 2.7. Mid leg: femur 3; tibia 3.4. Hind leg: femur 3.7, tibia 3.4. Wing: length 11.2, width 3.4; R2+3 3; bRs 2.5; dRs 1.1; R4+5 3.7.

Remarks.

The new species having ratio of bRs/dRs of 2.5 is similar to Epimesoplecia elenae Zhang, 2007, but is distinguished from the latter by having Rs bifurcation significantly distad of fork of M1+2 (vs. Rs bifurcation slightly distad of fork of M1+2); bM1+2 distinctly longer than dM1+2 (vs. bM1+2 clearly shorter than dM1+2); dM1+2 clearly shorter than r-m (vs. dM1+2 as long as r-m); dM1+2 short, almost one-eighth of M2 (vs. dM1+2 long, one-fifth of M2). Comparisons with other species are listed in Table 1.