• Location: Romblon Island

  • Depth: shallow / medium depth

  • Cover Photo: Christophe Kazmierski

  • Scientific Name: Cyerce blackburnae (K. Moreno, Gosliner, N. G. Wilson, Krug & Á. Valdés, 2025), before known as Cyerce sp. / Cyerce cf. bourbonica

Cyerce blackburnae: A Stunning Discovery in Philippine Waters

Cyerce blackburnae is one of the most recently described species of butterfly seaslugs, belonging to the fascinating family Caliphyllidae within the order Sacoglossa. This elegant marine gastropod was previously known to the diving community as a Cyerce sp. that closely resembled Cyerce bourbonica, but has now been recognized as a distinct species with its own unique characteristics.

A Case of Mistaken Identity

What makes Cyerce blackburnae particularly interesting to our diving resort in Romblon is how it demonstrates the ongoing evolution of marine taxonomy. For years, underwater photography enthusiasts and marine biologists encountered this beautiful seaslug during scuba diving expeditions, often identifying it as the similar-looking Cyerce bourbonica. However, detailed scientific analysis revealed significant differences that warranted its recognition as a separate species.

Characteristics and Identification

Like other members of the Cyerce genus, Cyerce blackburnae displays the characteristic butterfly-like cerata (finger-like projections) that give these seaslugs their common name.

Habitat and Distribution

Cyerce blackburnae has been documented in Indo-Pacific waters, particularly thriving in the pristine coral reef environments around Romblon. The species typically inhabits areas with abundant algal growth on reef slopes and coral gardens, where it finds both food sources and natural camouflage among the diverse marine vegetation. For underwater photography specialists, the clear waters around Romblon provide good visibility for macro photography, making it an ideal location for capturing detailed images of these cryptic creatures.

Photography and Diving Opportunities

The discovery and formal description of Cyerce blackburnae highlights the incredible biodiversity that exists in Romblon’s marine environments. For scuba diving enthusiasts visiting our diving resort, encountering this species represents both a photographic challenge and a scientific opportunity. These seaslugs require keen observation skills and patience to locate, as their excellent camouflage and small size make them elusive subjects for underwater photography.

Conservation and Research Importance

The description of Cyerce blackburnae underscores how much we still have to learn about marine biodiversity, even in well-studied groups like seaslugs. Every newly described species adds crucial information to our understanding of marine ecosystems and emphasizes the importance of continued research and conservation efforts.

For guests at our diving resort in Romblon, spotting Cyerce blackburnae during scuba diving expeditions represents not just an exciting wildlife encounter, but a connection to cutting-edge marine science. The species serves as a reminder that the waters around Romblon continue to yield new discoveries, making each dive an opportunity for both adventure and scientific contribution.