Moray Eels (Muraenidae)

  • Giant Moray (Gymnothorax Javanicus)

    Giant Moray Eel (Gymnothorax Javanicus)
    There are 4 images in this gallery
    Thu, 12/23/2010 - 21:07

    Growing to a maximum length of between 2 - 3m, the Giant Moray Eel (Gymnothorax Javanicus) is the largest, although not the longest member of the Moray Eel family in terms of body mass and bulk, in much the same way as the Green Anaconda is considered the largest living snake as opposed to the longer Reticulated Python.

    The title of the world's longest Moray Eel actually goes to the Slender Giant Moray Eel, also known as the Gangetic Moray Eel (Strophidon Sathete) which may reach lengths of up to 4m.

    Although Giant Moray Eels may historically have attained a fearsome reputation, this is due almost entirely to their appearance and size rather than attacks on humans.

    As a shy, reclusive, nocturnal hunter, attacks on humans are incredibly rare and are almost certainly the result of provocation or self defense.

    Adult Giant Morays are easy to identify due to their size alone, although other distinguishing features include an overall brown/green-ish colouration with dark spots, which in some cases give the appearance of a leopard-like pattern. There is also a dark marking around the circular gill opening.

    As with other members of the Muraenidae family, they lack pectoral fins, whilst the dorsal fins form a single, continuous fin from the rear of the head to the tail.
    They have relatively small dark, red-ish/brown eyes and pronounced nostrils, both of which are evidence of their nocturnal nature and heavy reliance on their sense of smell rather than sight.

    One peculiar feature which i've observed often with this species is what appears to be a covering over the teeth. This "covering" seems more like skin in the process of being shed, rather than a permanent covering. So far i've been unable to find any mention of it in reference material.

    With a diet consisting mainly of small fish and crustaceans, Giant Morays are unlikely to have any natural predators of their own, with only human hunters posing them any real danger.

    The Giant Moray, although extremely common on Thailand's west coast, is rarely seen in local waters although there is what appears to be a very small, isolated population at Sail Rock, Koh Phangan.

  • Palechin Moray Eel (Gymnothorax Herrei)

    Palechin Moray (Gymnothorax Herrei)
    There are 3 images in this gallery
    Thu, 12/22/2011 - 15:40

    The Palechin Moray (Gymnothorax Herrei) is one of the smallest and most elusive of the Moray species found in local waters.

    Growing to a maximum length of only around 30cm, the size alone makes identifying this species fairly easy.

    Unlike many other Morays, the Palechin lacks any pattern markings, instead being an overall pale brown/pinkish colour that because lighter around the face and beneath the jaw area.

    Although they are probably fairly common, the Palechin Moray spends almost all of time (during daylight at least) hiding in deep crevices or beneath the layers of stinging Anemones such as Amplexidiscus Fenestrafer which offer them protection against larger predators such as Groupers.

    They are usually found at depths between 10 - 20m at the deeper offshore sites such as Sail Rock and Chumphon Pinnacles, although it is likely that they have a greater location and depth range.

  • Undulated Moray (Gymnothorax Undulatus)?

    Undulated Moray (Gymnothorax Undulatus)
    There is 1 image in this gallery
    Wed, 12/29/2010 - 11:04

    Of the small number of locally occurring members of the Moray (Muraenidae) family, the Undulated Moray (Gymnothorax Undulatus) is the one for which positive identification is the most uncertain.

    Of the numerous photos of this species that appear in reference books or websites, not many appear to closely match the species found in local waters.

    A general description of the species on the fishbase website suggests a maximum length of around 1.5m and a "distinctive pattern of light undulating lines and speckles on a dark green background".
    Some of its other common names, such as Leopard Moray and Mottled Moray throw even more doubt on this identification as it certainly does not appear to have a leopard-like appearance.

    These common names and the physical description matches most of the available photos of the species, but do not seem to closely match the species featured here, particularly the undulating lines and speckles.

    As, like most Morays, only the head is generally seen, there is the possibility that the markings described above are present, but not visible during most encounters.

    Another obstacle to positive identification is the fact that this is a very elusive species which is seldom seen. It appears from time to time at Sail Rock, Koh Phangan, although is likely to be more widespread.

    Until a more confident identification can be made, i will leave this species tentatively named as it is, but i will also include it in the "unidentified" section of the gallery.

  • White-Eyed Moray Eel (Siderea Thyrsoidea)

    White-Eyed Moray Eel (Siderea Thyrsoidea)
    There are 3 images in this gallery
    Tue, 12/20/2011 - 22:04

    The White-Eyed Moray Eel (Siderea Thyrsoidea) is by far the most frequently encountered species of Moray Eel in local waters.

    Growing to a maximum length of around 70cm, the White-eyed Moray is easily distinguished by its overall brownish colouration which has a gold, speckled pattern, particularly on the dorsal area.

    As the name suggests, the eyes are white and there are rows of sensory pits around the face area.

    This species can be found at most of the frequently visited dive and snorkelling sites in the area, although it appears to be far more common at the offshore sites such as Sail Rock, Koh Phangan.

    As with most of its relatives, the White-Eyed Moray is a primarily nocturnal hunter, spending most of the day resting in holes or crevices, with only the head being visible.