SEAVR 2019: 048‐049
ISSN: 2424‐8525
Date of publication: 23 April 2019
Hosted online by ecologyasia.com

Recent record of the Tiger Freshwater Moray Gymnothorax polyuranodon,
and an updated location list for the Philippines
John Paul V. QUINDO & Abner A. BUCOL
abnerbucol2017@gmail.com (Bucol)

Observers: John Paul V. Quindo, Abner A. Bucol.
Photograph by: Abner A. Bucol.
Subject identified by: Abner A. Bucol.
Location: Nangka, Bayawan River, Negros Oriental, Philippines (9.397545°N, 122.815191°E).
Elevation: 12 metres.
Habitat: River with denuded banks and patchy vegetation, about 7.73 km from the river mouth.
Date and time: 23 December 2018, 09:00 hrs.
Identity of subject: Tiger Freshwater Moray, Gymnothorax polyuranodon (Pisces: Anguilliformes: Muraenidae).
Description of record: Whilst undertaking fish sampling in the upper station (Barangay Nangka) of the Bayawan
River the first author, along with local fishermen, captured a single specimen of the rare Tiger Freshwater Moray,
Gymnothorax polyuranodon, measuring 372 mm in total length (Fig 1).

Fig. 1.

© Abner A. Bucol48

Remarks: This species can be readily distinguished from other morays in the Philippines by having black blotches
on a yellowish to creamy white background. Among the muraenids, it is the only known species in which adults
spend much of their life in freshwater but return to the marine environment to spawn (Ebner et al, 2011;
Tsukamoto et al, 2014). Juveniles of the species may also inhabit estuarine areas (Mailautoka and McCosker
2012).
According to Mailautoka and McCosker (2012), G. polyuranodon has the following known distribution:
Australia, Brunei Darussalam, Fiji, Indonesia, Malaysia, Micronesia, Federated States of New Caledonia, Palau,Papua New Guinea, Philippines, Sri Lanka and Taiwan, Province of China.
In the Philippines, however, only a few records of this species can be found in the literature. Herre (1924) was thefirst to describe this species as one of the rare eels in the Philippine archipelago. An updated list of localities
where this species occur is provided under Site Summary:
Site Summary:
1. Saub River, Cotabato, 1 specimen obtained by E.H. Taylor, 4 km from the sea, April 29, 1923 (Herre, 1923)
2. Craan River, Cotabato, 2 specimens obtained by E.H. Taylor, 4 km from the sea (Herre, 1924)
3. Brook at San Ramon Penal Colony, Zamboanga as reported by FishBase (Froese and Pauly, 2019)
4. Canigaran, Palawan, as reported by FishBase (Froese and Pauly, 2019). Probably based on Herre, 1923, citing arecorded by Boulenger in 1895.
5. North Bais Bay, Negros Oriental in 1988, now at Silliman University Fish Collection (SUML‐FI MUR 0004, coll:
CLRP, identified by M.L. Dolar), as reported by FishBase (Froese and Pauly, 2019).
6. Siaton River; 15‐30 km from the rivermouth, Siaton, Negros Oriental; 1 specimen captured by E.E. Carumbanaand local fishermen; now at the United State National Museum (USNM 385604); February 2004 (Bucol andCarumbana, 2010).
7. Sicopong River; Barangay Kabulakan (9.374778°N, 122.883050°E), 7.2 km from rivermouth, Sta. Catalina,
Negros Oriental; 1 specimen captured by R. S. delos Santos using a fishing rod; February 16, 2019.
8. Bago River; 1 specimen captured by J. Linaugo (La Consolacion College‐Bacolod) and party in upper stations ofthe Bago River (10.560413°N, 123.118811°), about 35.6km from rivermouth, in 2010 (Bucol et al. 2010).
References:Bucol, A. A., and Carumbana, E. E. (2010). Checklist of fishes found in the fresh and brackish waters of Negros andSiquijor, Philippines. Asian Journal of Biodiversity 1(1): 91‐125.
Bucol, A. A., Menes, C. C., Linaugo, J. D., and Pacaliioga, J. O. (2010). The Anguilliform Eels (Pisces: Anguilliformes)of Bago River and Adjacent Waters in Negros Occidental, Philippines. Silliman Journal 51(1): 89‐103.
Ebner, B. C., Kroll, B., Godfrey, P., Thuesen, P. A., Vallance, T., Pusey, B., ... Perna, C. N. (2011). Is the elusive
Gymnothorax polyuranodon really a freshwater moray? Journal of Fish Biology, 79(1), 70‐79.
Froese, R. and D. Pauly. Editors (2019). FishBase. World Wide Web electronic publication. www.fishbase.org(02/2019).
Herre, A.W.C.T. (1923). A review of the eels of the Philippine Archipelago. The Philippine Journal of Science 23(2):123‐236.
Herre, A.W.C.T. (1924). Some rare Philippine eels. The Philippine Journal of Science 24(1): 107‐111.
Mailautoka, K. & McCosker, J. (2012). Gymnothorax polyuranodon. The IUCN Red List of Threatened Species 2012:e.T195780A2416879. http://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T195780A2416879.en. Downloaded on 27
March 2019.
Tsukamoto, K., Watanabe, S., Kuroki, M., Aoyama, J., Miller, M. J. (2014). Freshwater habitat use by a moray eel
species, Gymnothorax polyuranodon, in Fiji shown by otolith microchemistry. Environmental biology of fishes,
97(12), 1377‐1385.

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