Eminepygia myanmarensis Chen & Zhang 2021, sp. nov.
Creators: name: Chen, Xin-Yu
name: Zhang, Hua-Chuan
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Dermaptera
Pygidicranidae
Eminepygia
Eminepygia myanmarensis

description: Eminepygia myanmarensis sp. nov.
(Figs. 1‒5)
Etymology. The specific name is the Latinized Burmese word “ Myanmar ” referring to the country from which the material originates.
Type material. Holotype, CSCLRCAB100190, well-preserved; deposited at the Cores and Samples Center of Land & Resources (CSCLR), Sanhe, Hebei, China.
Locality and horizon. Hukawng Valley, Kachin State, Northern Myanmar; lowermost Cenomanian, mid-Cretaceous.
Diagnosis. As for the genus.
Description. Holotype: third-instar nymph. Medium-sized earwig, 5.5 mm in length (excluding antennae and cercal forceps) (Fig. 1); head 0.80 mm long, 0.83 mm wide. Integument (as preserved) brown to light brown; strongly imbricate with shallow, weak, coarse punctures and sparse long setae.
Head (Fig. 2) prognathous, with medial length from clypeal to posterior border 0.69 mm, maximum width across compound eyes 1.17 mm; surface not tumid; ecdysial cleavage scar clearly “Y”-shaped (Fig. 2; ec), postocular ridge present albeit weak; temple corners acute with series of stiff, erect setae, such setae extending along posterior margin of head, length of head behind compound eye 0.83 mm; clypeus (Fig. 2; c) with scattered, relatively long setae; maxillary palpus (Fig. 2; mp) visible but not clear, with short sub-appressed setae; lacinia (Fig. 2; l) slender, with two apical teeth; galea (Fig. 2; g) highly sclerotized with one dagger-shaped tooth.
Compound eyes 0.21‒0.23 mm (Fig. 2; e), ellipsoid, medium-sized, prominent and exophthalmic, interocular distance 0.93 mm; ocelli absent; ventral cervical sclerites (Fig. 2; vcs) of equal size.
Antenna 1.84–1.93 mm (Fig. 2; a), with at least 11 antennomeres; scape relatively robust, length 0.31–0.33 mm; pedicel short, about one-fourth as long as the scape; meriston 0.28 – 0.30 mm long, length approximately three times the width, slightly thinner than scape; the subsequent flagellomere about as long as wide, remaining flagellomeres longer than width.
Pronotum (Fig. 3; prn) subrectangular, 1.13 mm wide, 0.92 mm long, with elongate, prominent, stiff setae at anterolateral corners and 2-3 short, stiff prominent setae near or at posterolateral angles; scutellum not present. Mesonotum (Fig. 3; msn) wider than long, 1.08 mm wide, 0.85 mm long, posterior border faintly and broadly convex, anterior margin covered by posterior margin of pronotum; metanotum (Fig. 3; mtn) 0.62 mm long, 1.19 mm wide, posterolateral angles broadly rounded, anterior margin covered by posterior margin of mesonotum.
Legs (Fig. 4) short, with spines or bristle-like setae on dorsal surface of femora; tarsi trimerous; forecoxae close but separated; fore femur thick and short, 0.63 mm long, 0.14 mm wide; middle femur 0.68 mm long, 0.18 mm wide; hind femur (Fig. 4; hf) 0.87 mm long, 0.19 mm wide; hind femur more swollen than other femora; tibia slightly longer than tarsi combined; pretarsal claws simple, arolium absent; tarsomere I (Fig. 4; t 1) elongate, with dense setae along ventral surface; tarsomere II (Fig. 4; t 2) blunt apically, not extending beneath the distalmost tarsomere; tarsomere III (Fig. 4; t 3) elongate, slightly shorter than tarsomere I; pretarsal claws long, simple; arolium absent.
Abdominal length 3.77 mm (excluding cerci), all ten transverse segments visible (Fig. 5), first five segments and last five segments nearly equal in length; lateral abdominal margins gently convex; terminal tergum 0.28 mm long, 0.72 mm wide, as long as tergite IX, with straight peg-like tubercle (Fig. 5; st) on posterior border; prominent bulges (Fig. 5; b) present, rising from lateral margins of tergite VIII, extending onto the lateral margins of tergite IX triangularly, and slightly extending past anterior border of tergite X.
Cercal forceps short, symmetrical, apices acute, curved and unsegmented, length 0.54 mm, separation between bases 0.32 mm; the inner edges appearing gradually arching; pygidium (Fig. 5; p) simple, segmented and basally subtriangular, without ornamentation, visible only on ventral view; paraproct (Fig. 5; pr) obvious.
Comments. In early instars the flagellomeres are poorly differentiated (Ren et al., 2018). The greatly elongated meriston and the reduced number of total flagellomeres are suggestive of an early instar (Brindle, 1987). The weakly swollen, paler lobes of the metanotal posterolateral area and the elongate meriston demonstrate some degree of development, thus suggesting that the specimen is likely a third instar.
description: Published as part of Chen, Xin-Yu & Zhang, Hua-Chuan, 2021, Eminepygia myanmarensis sp. nov., a new Earwig (Dermaptera) Nymph in Burmese Amber, pp. 571-579 in Zootaxa 4952 (3) on pages 573-574, DOI: 10.11646/zootaxa.4952.3.9, http://zenodo.org/record/4690708