Thecacera melkyi

Thecacera melkyi, informally known as Thecacera sp., is a species of nudibranch (sea slug) in the family Polyceridae, described from Timor-Leste and also recorded in Indonesia and Japan.

Taxonomy

Thecacera melkyi was formally described as a new species by Manuel Pola and colleagues in 2026. The species was collected in East Timor, which serves as its type locality. The epithet melkyi is a dedication to an individual named Melky. It belongs to the genus Thecacera, established by Fleming in 1828, and is classified within the family Polyceridae. No synonyms or subsequent reclassifications have been reported for this species since its description.

Description

The body of Thecacera melkyi is generally cream to orange, differing from the brighter yellow of T. pikachu. It features black dorsal spots that form a characteristic pattern converging into a Y-shaped arrangement toward the tail tip. The rhinophoral sheaths and extra-branchial processes are entirely dark brown. The species has a compact, elongate body plan typical of Thecacera, with paired rhinophores and prominent extra-branchial processes. Thecacera melkyi can be distinguished from T. pikachu by its cream-orange background colour, dark-brown appendages, and the distinctive dorsal black-spot arrangement.

Distribution and habitat

The species is found in shallow-to-moderate-depth reef environments. The currently documented observation of Thecacera melkyi is at a depth of 22 m. The geographic distribution of the species includes Timor-Leste and at least Ambon, Indonesia. A verified substrate preference for Thecacera melkyi has not been established in the available sources.

Diet

Thecacera melkyi is reported to feed on bryozoans and hydroids, apparently at night. As a polycerid nudibranch, it feeds by using its radula—a toothed rasping structure—to scrape or rasp prey from the substrate and ingest it.