Abaddonella nwarrngaal, Schall & Heads & Husemann, 2025

Abaddonella nwarrngaal sp. nov.

Figs 1 View Figure 1 , 2 View Figure 2

Etymology.

Nwarr ngaal is Burmese and means “ little cow ”. It refers to the conspicuous color markings on the species’ head and pronotum.

Locality and horizon.

The specimen was included in amber found in Hkamti , Sagaing Division, Myanmar or Tanai , Kachin State Burma, Myanmar, two nearby amber mining locations. The amber from Hkamti is ca. 110 My and the amber from Tanai ca. 99 My old.

Holotype.

Male. Specimen part of the LIB-Hamburg collection; collection number GPIH 07231 View Materials (ex coll. Martin Husemann, coll. no. MH 0086).

Diagnosis of species.

As for genus (monotypic).

Description.

A fully preserved specimen, except for left metathoracic leg.

Measurements: Values given with a “ ca. ” indicate measurements based partly on estimation. Body-length ca. 1.83 mm. Head height 0.68 mm. Compound eye height 0.31 mm, width 0.21 mm. Antenna length 0.85 mm. Pronotum length 0.54 mm, height 0.4 mm. Forewing length 0.55 mm, hindwing length 1.64 mm. Prothoracic leg: femur 0.38 mm long. Tibia 0.36 mm long. Mesothoracic leg: tibia 0.5 mm long. Femur / Tibia width = 1.07 (at mid of both). Metathoracic leg: femur ca. 0.86 mm long, 0.51 mm wide. Tibia ca. 0.79 mm long, ca. 0.09 mm wide (around mid-length). Tarsus> 0.31 mm long. Cercus 0.15 mm long. Paraproctal lobe ca. 0.05 mm long. Subgenital plate 0.18 mm long.

Head: Antennae 10 - segmented, moniliform. Pedicel and scape wider than antennomeres. Head with two small bumps on the vertex in front of the compound eyes. Compound eyes placed laterally on the head. Head with distinct coloration; a lighter area crosses the eye dividing it into two equal parts and continuing on the dorso-lateral portion of the head. Ocelli not seen.

Thorax: Pronotum with similar light / dark contrasting colors as head, but here the base color is light and several dark spots are scattered across the surface. Pronotum without elevation. Both fore- and hindwings present. Forewings with same color pattern as pronotum, hindwings uniformly dark. Hindwing slightly longer than abdomen.

Legs: Prothoracic leg: femur bearing some long hairs. Tibia slightly inflated, completely covered with shorter to longer hairs. Apically with three dactyls, the longest of which is 0.05 mm long. Tarsus slender, only distal segment can be seen, bearing two curved claws.

Mesothoracic leg: femur with some short hairs on both margins. Femur rather slender towards coxa, becoming wider towards tibia. Tibia slightly inflated, but not as wide as distal part of femur. Tibia apically with dense long hair. Tarsus slender with two claws.

Metathoracic leg: femur inflated along its entire length. Tiger stripe coloration, which can be seen on the metafemur of the specimen is probably due to fissures in the amber and not actual coloration. Connection to tibia damaged. Tibia with lateral carina that runs until apex. Fin with distinct serration. Subapical and apical spurs present, approximately the same length. Tarsus proportionally long and rather thin. Ventrally with eight to nine hairs. Apex of tarsus hidden behind mesotibia.

Abdomen: Epiproct short, not covering cercus. Cercus one-segmented, cylindrical in shape and with many long hairs. Paraproct distinct with paraproctal lobe in ventral position. Paraproctal lobe significantly smaller than cercus (both length and width), cylindrical without hairs. Subgenital plate elongated, approximately the length of the cercus and with long hairs; one especially long hair on the apex. Subgenital plate mostly dark in coloration becoming slightly lighter towards apex. Cercus completely of lighter color.

Remarks.

The new genus is assigned to Ripipterygidae based on the following characters: 1) cercus one-segmented. 2) Mesotibia not inflated. It is most similar to Burmaripipteryx Zhao, Xu, Jarzembowski, Fang & Xiao, 2023 but differs from the latter by the two bumps on its forehead and the coloration pattern of the head, pronotum as well as external genitalia ( B. oblongus Zhao, Xu, Jarzembowski, Fang & Xiao, 2023 , only species of the genus, has cerci with the basal half light in color and the distal half dark, while the subgenital plate is completely light. Head and pronotum show no noteworthy color pattern). These characters also differentiate Abaddonella from any other ripipterygid-genus. The underdeveloped paraproctal lobes of this genus and also Burmaripipteryx (much smaller than cerci, of no distinct shape and without apical setae) are rather unusual for Ripipterygidae . According to Song et al. (2015), the estimated split between the lineages of Ripipterygidae and Tridactylidae occurred 153.45 Mya, ca. 50 My prior to the formation of the Kachin amber from Tanai. Maybe, at this point in time the separation of the two families had not yet been fully completed and a third lineage, ancestral to both, still existed. This is a question that will be answered with more findings of Tridactyloidea from Kachin amber in the future. For now, we follow Zhao et al. (2023) and place Abaddonella in Ripipterygidae .