Citizen science yields first records of Hippocampus japapigu and Hippocampus denise (Syngnathidae) from Taiwan: A hotspot for pygmy seahorse diversity.

Joseph Heard,Colin K C Wen,Jeng-Ping Chen

doi:10.3897/zookeys.883.39662

Abstract

Relatively very little is known about pygmy seahorses, and even basic information regarding their distributions is largely inconsistent and often based on unofficial reports. However, monitoring marine diversity, particularly for small and cryptic species, such as pygmy seahorses, can be both costly and time consuming. In such cases, the use of citizen science can offer an effective tool for addressing knowledge gaps caused by a lack of biodiversity-related data. Scuba divers and underwater photographers were engaged through social media in order to investigate pygmy seahorse diversity in Taiwan. Using this approach five species of pygmy seahorses were identified, including two new records for Taiwan: Hippocampus denise and Hippocampus japapigu, the latter of which is the first record of the species from outside of Japan. These new records mark Taiwan as one of the world’s pygmy seahorse diversity hotspots, matching that of Japan and Indonesia, as well as demonstrating the value of citizen science for marine biodiversity monitoring, particularly for small cryptic species.

Highlights

There are currently seven species of pygmy seahorse contained within the syngnathid genus Hippocampus Rafinesque, 1810 (Lourie et al 2016)
We engaged underwater photographers and dive guides through citizen science via social media in order to improve the current knowledge of pygmy seahorse diversity in Taiwan, where three species: H. bargibanti Whitely, 1970, H. colemani, and H. pontohi have so far been observed by scuba divers (Shao et al 2008; Short et al 2018)
Our search results returned 259 social media items, 75 of which included in situ photographs of pygmy seahorses from five different locations in Taiwan (Fig. 1)

Summary

Introduction

There are currently seven species of pygmy seahorse contained within the syngnathid genus Hippocampus Rafinesque, 1810 (Lourie et al 2016). The majority of pygmy seahorse species are known from a limited number of locations. With the exceptions of H. pontohi Lourie & Kuiter, 2008 and H. japapigu Short et al, 2018, all other pygmy seahorse species are currently classified as “Data Deficient” on the IUCN Red List of Threatened Species.

Results

Conclusion