Venom effects and medical significance are different from toxicity rankings. Do not handle a snake on the basis of this summary.
A very small head and narrow front body contrast strongly with the thicker rear body. The cited diagnosis reports 17–21 neck scale rows and 30–36 around the thickest part. Its atlas account links 1 named island or island-group record to the source literature.
OccurrenceConfirmed
Islands named1
Natural history6 sourced topics
References3
Literature updated 2026-10-07 · Editorial review pending
Reserved for a contributor imageCredit and usage rights will accompany the image.
The illustrated collection
Adult & juvenile
Adult · study plate
Microcephalophis gracilis
Image to follow
Reserved for a contributor imageCredit and usage rights will accompany the image.
Juvenile · study plate
Microcephalophis gracilis
Image to follow
Reserved for a contributor imageCredit and usage rights will accompany the image.
Life stages will be labelled from the contributor’s information. Images alone do not establish identification or a locality record.
Media provenance
Every image carries its source.
Contributor images are forthcoming. Photographs and illustrations will retain their individual credits, permissions and evidence notes.
One species · Across borders
Global distribution
Countries and territories named in the checked sources. Island links and country lists use these same occurrence records; a country record does not imply presence on every island.
Checked 7 October 2026. Listed, introduced and uncertain records remain distinct. Islands not yet indexed are not claims of absence. Broad references such as “Borneo” or “New Guinea” are not automatically assigned to every country sharing the island.
Indonesian locality notes and qualifications
Explicit Indonesian country or island locality supports inclusion.
Coastal island outlines are geographic context, not a mapped marine range.
Appearance & identification
A very small head and narrow front body contrast strongly with the thicker rear body. The cited diagnosis reports 17–21 neck scale rows and 30–36 around the thickest part.
Species-level database summary; literature review, not expert validation.
The cited account does not establish population-wide variation or the conditions at every Philippine locality.
Diet & foraging
The account associates the specialised narrow head and front body with hunting eels in burrows. This ecological interpretation does not supply a Philippine prey-frequency dataset.
Literature documented · Comment: ecology; Voris & Voris (1983)
Species-level database summary; literature review, not expert validation.
The cited account does not establish population-wide variation or the conditions at every Philippine locality.
Reproduction
The species account records live-bearing reproduction, using the term ovoviviparous. A verified Philippine litter-size range and reproductive calendar are not established here.
Reproductive mode reported for this named species.
Mode alone does not establish litter or clutch size, seasonal timing, or captive husbandry requirements.
Ecology & habitat
The account records a marine habitat. Island names on the map identify reported coastal areas; they are not land occupancy or a boundary of the species’ marine range.
Species-level database summary; literature review, not expert validation.
The cited account does not establish population-wide variation or the conditions at every Philippine locality.
Taxonomic context
Microcephalophis gracilis is retained in the atlas’s dated checklist under Elapidae. The authority is (SHAW 1802). Earlier names and the original source notes are preserved below for comparison.
Literature documented · Checklist identity and nomenclatural trail
Checklist verified 2026-09-05; not a newly revised taxonomic backbone.
Historical names can cover different biological concepts; synonyms should not be used to transfer records automatically.
Across the archipelago
Where this species is recorded
PhilippinesN ↑
Coastal records: blue outlines
Blue outlines locate coastal records, not land occupancy or marine range boundaries.
Philippine distribution
Documented places
Manila Bay.
1 named island / island group
Select an island to read its distribution record and sources. Uncoloured islands are not evidence of absence.
Distribution record & sources
Indian Ocean: Pakistan, India (Gujarat etc.), Sri Lanka, Bangladesh, Myanmar (= Burma), Thailand, Philippines,
South China Sea northward to the coast of Fujian (China), Vietnam,
Persian Gulf to Bay of Bengal (Oman, United Arab Emirates, Iran)
Coast of Peninsular Malaysia through Indoaustralian Archipelago to New Guinea,
Melanesia
Indonesia (Borneo)
Type locality: not given (fide O’SHEA 1996)
Venomous · Effects not yet summarised in this atlas
Observe from a distance. Do not handle, corner or capture a snake to identify it. An incomplete venom account is not evidence that a species is safe to handle.
After a suspected snakebite, keep the person still and arrange urgent medical care. Avoid tight tourniquets, cutting, suction and unproven remedies. Do not wait to identify the snake before seeking help.
Distribution reviewed against cited source (p. 468). Manila Bay.
Islands named
Luzon
Range noteCountry/island text is not a range polygon or locality record.
Source distribution statement
Indian Ocean: Pakistan, India (Gujarat etc.), Sri Lanka, Bangladesh, Myanmar (= Burma), Thailand, Philippines,
South China Sea northward to the coast of Fujian (China), Vietnam,
Persian Gulf to Bay of Bengal (Oman, United Arab Emirates, Iran)
Coast of Peninsular Malaysia through Indoaustralian Archipelago to New Guinea,
Melanesia
Indonesia (Borneo)
Type locality: not given (fide O’SHEA 1996)
Knowledge coverage
EndemismResearch pending
EcologyLiterature documented
VenomVenomous Effects not yet summarised in this atlasDetailed research: Research pending
Venomous!
Synonymy partly after COGGER 1983 and STEJNEGER 1907.
Type species: Hydrus Gracilis SHAW 1802 is the type species of the genus Microcephalophis LESSON 1832.
Phylogenetics: we follow Sanders et al. 2012 in recognizing Microcephalophis as a clearly distinct lineage. Microcephalophis is one of at least 15 microcephalic Hydrophis group species specially adapted for hunting eels in burrows, with small heads and hind-body girths more than twice to five times the girth of the fore-body (Voris and Voris, 1983).
Distribution: Erroneously reported from New Caledonia fide BAUER & SADLIER 2000. Reports from New Caledonia turned out to be H. coggeri (Rasmussen 2014). Not in Australian waters fide Rasmussen 2014. Reports from Australia are doubtful or misidentifications (e.g. of H. elegans).
Habitat: marine.
References attached to this record
2026
The Reptile Database — species checklist, 17 June 2026
Microcephalophis gracilis — The Reptile Database species account
Uetz, P.; Hallermann, J. et al. (editors)
Public species fields consulted for bounded biological summaries. Primary sources quoted within the database were not independently examined unless explicitly stated. The catalogue name may differ from the current source title.