Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Synbranchiformes
(Spiny eels) > Mastacembelidae
Etymology: Macrognathus: Greek, makros = great + Greek, gnathos = jaw (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical; 26°N - 25°N, 96°E - 97°E
Asia: Myanmar. Known from Lake Indawgyi and an unnamed small hill stream south of Mogaung, Kachin State, northern Myanmar (Ref. 84451).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 21.6 cm SL male/unsexed; (Ref. 84451)
Morphology | Morphometrics
(total): 21 - 22;
soft rays: 50 - 51;
Vertebrae: 74 - 75. Macrognathus aureus is a member of the M. aculeatus species group. It differs from all other members of this species group by the following combination of characters: rostral tooth plates 8–10, dorsal-fin spines 21–22, and a unique colour pattern consisting of a series of large white rimmed dark-brown to black blotches along the dorsal fin and even larger black blotches along the lateral line, of which some are confluent with the dorsal series. In particular it differs from M. aral, M. lineatomaculatus, M. pentophthalmos, M. siamensis, M. tapirus, and M. aculeatus in having fewer rostral toothplates (8–10 vs 11–55), from M. pavo, M. morehensis, M siamensis, M. meklongensis, and M. pentophthalmos in having a greater number of dorsal-fin spines (21–22 vs 4–18). The only species of the M. aculeatus group with a similar range in the number of rostral tooth-plates and dorsal-fin spines is M. obscurus, from which the new species differs in its colour pattern (large white rimmed dark brown to black blotches along the dorsal fin and the lateral line, of which some are confluent with the dorsal series, vs minute or absent dorsal fin spots and absence of lateral line blotches) (Ref. 84451).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Britz, R., 2010. Macrognathus aureus, a new spiny eel of the M. aculeatus species group from the Upper Ayeyarwaddy River Drainage, Myanmar (Teleostei: Synbranchiformes: Mastacembelidae). Zootaxa 2514:55-60. (Ref. 84451)
IUCN Red List Status (Ref. 115185)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00302 (0.00138 - 0.00659), b=2.91 (2.72 - 3.10), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.3 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (26 of 100) .