Currently no ray species can be legally exported from the country. <> The protruberances are the pelvic “bones” and should not be visible in a well-fed ray. : elasmobranchs with low urea content. Tank maintenance must be similarly stringent. Developmental stages of the stingray Trygon pastinacum, a representative of early fishes with intra-uterine embryogenesis. Rays can be picky when it comes to selecting a mate. pp. Hyg. McKee, R.E. For example some ray keepers suggest that discus make good tankmates, while others have reported that smaller fish such as these are picked off by their rays at night. Basic Author Observations of the riverine ray. IV. all my rays eat like pig,so far on average slowest growth is 1/2''per mth and fastest is 1''per mth,so very hard for me to believe 2''per mth!! 1970. 1. Dim lighting is preferable, although once settled in most rays will also be active under brighter conditions. & E.J. Z.H. Copeia 1980: 900–901. J. Morph. Alternatively install one or more high qualty external canister filters. However this is probably beyond the means of most hobbyists. PubMed Google Scholar, Thorson, T.B., Langhammer, J.K. & Oetinger, M.I. In: P.P. Vol. 17: 379–410. 1945. In another words females will grow faster after that size. Cheers.. i got a 6" motoro last december, now it around 9-10". They’re active fish with a high metabolic rate and as such will need feeding at least twice a day. Potamotrygon species utilise a breeding strategy known as matrotrophic viviparity. Mem. Before buying a ray please read as much as you can on the subject. Introduction. If selecting a single pair try to choose similarly patterned specimens, and a bigger female than male. If you can see a bony-looking growth protruding on each side of the caudal peduncle, this is a clear indication of malnutrition. Conversely they also seem to prefer a quiet life and will often fail to thrive when kept alongside very aggressive or territorial companions. Clark, R.S. Our results described here show that the nociception is mainly induced by venom from young female stingrays. Investigations of the Ichthyofauna of Nicaraguan Lakes, School of Life Sciences, Univ. Successful captive breeding of several species has occured regularly in recent years, . La Marca, M.J. 1964. Reproduction, life history, and ecology of the round stingray, Urolophus halleri Cooper. Med. One potential pitfall when keeping more than one species of Potamotrygon together is that most will hybridise freely. They are aplacentally viviparous, the young being nourished in advanced stages by uterine milk secreted by trophonemata. Old-timers at the aquarium. These are used to inseminate the female when mating and are clearly visible, appearing as finger-like extensions extending backwards from the inside of the fin. (Ser. We find this process abhorrent, and urge you not to buy these genetic misfits with the hope of stifling their popularity. The Potamotrygonids are part of the only group of Elasmobranchs that have evolved to occupy purely freshwater habitats. If stung, at the very least expect excruciating localised discomfort, headaches, nausea and diarrohea. (In Spanish). The venom is protein-based and contains a cocktail of chemicals designed to cause both intense pain and rapid tissue degeneration (necrosis). 36: 199–220. Arts Sci. Keep a close eye on developments if your rays begin to show signs of mating behaviour, and have the facilities on hand to separate them if need be. This species has a very wide natural range, taking in parts of Colombia, Peru, Bolivia, Brazil, Paraguay, Uruguay and Argentina. 1975. Halstead, B.W. McKee, R.E. Poisonous marine animals. More severe reactions than this are not uncommon, and medical advice should be sought no matter how serious the sting. pp. Size at onset and completion of sexual maturation, breeding season and behavior, gestation period, litter size and sex ratios are discussed. Libby, E.L. & P.W. Rpt. 1963b. Pregnant females are generally safe to be left in situ, although once the pups are born they’re best removed to avoid predation by other tankmates. Immediate online access to all issues from 2019. Biol. Assoc. Mem. 4 0 obj Gilbert. Castex, M.N. It’s essential to feed the female in sufficient quantities during this period as she will expend a lot of energy providing for her pups, and her appetite will increase significantly. Subscription will auto renew annually. Female rays will grows up to 1" per month after reaching 10" disc size. Inside the uterus of the female specialised filaments or villi develop. 120 pp. Thorson (ed.) Departamento de Ciencias, Colegio de la Inmaculada Concepción, Santa Fe, Argentina. Potamotrygon motoro is a freshwater stingray that belongs to the potamotrygonidae family. Whilst conservation projects have been suggested, a general lack of biological information regarding the various species, as well as frequent misidentification, has so far made the development of species specific management plans difficult. Biol., 1967, No. %���� They aren’t usually aggressive fish, using their sting only as a means of defence. Pt. Richards, S.W., D. Merriman & L.H. Cottrell, K. 1976. The actual stinging apparatus or spine is formed from dentin (the same substance that composes much of a human tooth) and possesses associated venom glands. Comp. <> Bingham Oceanog. They’re also notoriously big eaters and it’s going to cost you a considerable amount of money to keep even a single specimen in good health. U.S. Nat. Gilbert, P.W. Motoro stingray produce fully formed live young, these are known as “pups”. If you’re lucky enough to own a pair of rays that are breeding regularly, give the female a break from the male after every 2-3 litters. There are currently three genera in the family Potamotrygonidae, all of which hail from South America. Plenty of enthusiasts keep Asian or South American arowana with their rays, and in a roomy tank this can be a very striking combination. A net should never be used to catch a ray, instead use some kind of solid container or large fish bag. 2. The Brazilian government has recognised that a problem exists and stingray exports for the trade are now controlled by the Brazilian Environmental Agency (IBAMA). Sometimes pet shops sell it as a Mini Moss, it looks quite similar to Christmas moss. It’s been recorded in the main Amazon basinand numerous smaller rivers including the Rio Orinoco, Rio Uruguay, Rio Paraná and Rio Paraguay. Notes on the family Potamotrygonidae Garman, 1913. It goes without saying that the highest form of caution should be exercised when keeping rays. Many hobbyists like to hand feed their rays and this is fine as long as you’re careful. Marshall, N.B. If possible choose a sump–type arrangement, as this allows most of the equipment to be located outside the tank. Like other members of the genus it inhabits a variety of biotopes. Rays also like to bury themselves in sand when stressed and are usually found in sandy or muddy habitats in nature so to deny them the option of cover seems rather cruel to us. Like other rays they’ve also developed specialised breathing apparatus to allow them to breathe whilst lying in or on the substrate (the mouth and gills are on the underside of the fish, so can’t be used when the fish is at rest like this).