Pherodactylus micromorphus Poinar, Su & Brown, 2020

Cadena-Castañeda, Oscar J., Tavares, Gustavo Costa, Hu, Tian-Hao & He, Zhu-Qing, 2024, On the Myanmar amber field-crickets described as “ transitional ” mole crickets (Orthoptera: Gryllidea), Zootaxa 5555 (4), pp. 579-589 : 584-585

† Pherodactylus micromorphus Poinar, Su & Brown, 2020

= † Pseudogryllotalpa scalprata Gu, Yuan & Ma, 2024 syn. nov.

= † Petilus zhengi Gu, Yuan & Ma, 2024 syn. nov.

= † Unidigitus longialatus Gu, Yuan & Yue, 2024 syn. nov.

Comments. † Pseudogryllotalpa scalprata Gu, Yuan & Ma, 2024 syn. nov. is synonymized under † P. micromorphus . The specimen used to describe † P. micromorphus was a subadult female, while the type specimen of † P. scalprata syn. nov. is an adult female. Despite being females at different developmental stages, several characteristics are shared. † P. micromorphus had developing wings, which is one of the characteristics distinguishing it from † P. rectanguli , whose adult females are wingless. Unfortunately, the wing venation and shape of † P. scalprata syn. nov. are not visible. However, the shape of the tympanum and the apical spurs or dactyls in both † P. micromorphus and † P. scalprata syn. nov. match, as does the arrangement of the setae, spines, and spurs on the mid and hind tibiae. The congruence of these characters indicates they belong to the same species, thus the synonymy of † P. scalprata syn. nov. is effective. Besides, a lack of congruence is seen in the original description of the species and the genus. † P. scalprata syn. nov. is described as having an elongated pronotum, but for the genus, the pronotum is described as “relatively short and nearly quadrate in dorsal view.”

† Unidigitus longialatus Gu, Yuan & Yue, 2024 syn. nov. is synonymized under † P. micromorphus . The specimen on which the description of † U. longialatus syn. nov. was based is an adult female. The genus name † Unidigitus derives from only one dactyl on the fore tibia. However, according to the photographs in the original description, this does not seem to be the case. At least one additional dactyl appears to be broken, and the tarsal segments of at least the left foreleg are not fully preserved. Additionally, the apex and terminal appendages of this only foreleg present are clearly not well preserved, suggesting that additional dactyls may be lost. That raises questions about the supposed single dactyl on the foreleg. Does the same condition apply to the other foreleg? It is not specified in the original description, so verifying it would be interesting. In other characteristics, the specimen aligns with † P. micromorphus . The coloration of the † U. longialatus syn. nov. female follows the typical pattern of † P. micromorphus and † P. scalprata syn. nov. The tympanum is similar and present on both sides of the tibia, and the ovipositor shows no variation between the species compared here. Regarding the wings, the venation is not visible, but both forewings and hindwings are developed. It is not entirely clear for † P. scalprata syn. nov., as its original description does not mention fully developed hindwings, though they might be present, and the positioning of the photographs might obscure them. Based on the evidence presented here, the synonymy of † U. longialatus syn. nov. is established.

† Petilus zhengi Gu, Yuan & Ma, 2024 syn. nov. is also synonymized under † P. micromorphus . The specimen used to describe † P. zhengi syn. nov. is an immature female with the thorax partially separated from the abdomen, from which part of the organs and internal contents are exposed. In the † Petilus diagnosis, the genus is distinguished by “elongated pronotum; tympana present on the outer side only; tarsus relatively slender; short and thick ovipositor, laterally broadened.” The pronotum of † P. zhengi syn. nov. is described as elongated, but this could be a misinterpretation due to the separation of the thorax from the abdomen in the type specimen, giving the impression that the pronotum is more elongated compared to the other taxa discussed here. The tympana are only present on the outer side of the tibia, which is possible. In some cricket species, in nymphal stages, one or both tympana may not be fully formed and develop in subsequent stages or adulthood. Even in adult crickets, individuals can exhibit tympana at varying stages of development or even lack them altogether ( Cadena-Castañeda et al. 2022; Tavares et al. 2024). The dactyls and tarsomeres of the legs show similarities with the subadult or adult specimens of † P. micromorphus . The ovipositors of both species in their nymphal stages are also similar, except that in the holotype of † P. micromorphus , the valvae are slightly separated in the dorsal view. The coloration pattern of the † P. zhengi syn. nov. holotype is similar to † P. micromorphus and the other synonymized species exhibit lighter tones compared to the other analyzed specimens. Based on the arguments discussed, the synonymy of † P. zhengi syn. nov. is established.