


Shane's World Catfishology The White Seam Bristlenoses |
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| by Ingo Seidel, uploaded October 10, 2008 Translation by Kate McKay
Introduction Ancistrus dolichopterus or L 183 - the genuine Blue Bristlenose or White seam
Bristlenose. In its earliest youth, Ancistrus dolichopterus distinguishes itself from the very similar L071, which loses the white fin bands in adulthood, only by the number of fin rays. As far as science is concerned these two different species are not separated, since Ichthyologists do not have the luxury afforded to aquarists of being able to observe live fish and their colour at all stages of life. And so Fisch-Muller (1999, 2003) attributes to A. dolichopterus a much larger area of distribution than this species has in reality. Fisch-Muller concedes though, that A. dolichopterus never has as high a number of fin rays as those occurring in the Rio Negro basin. In my opinion the real A. dolichopterus (L 183) has never yet been detected anywhere else. According to Romer they can be found in the river system of the Rio Negro in black water and white water as well as in some types of clear water (see Evers & Seidel 2002, S 70ff). This species typically lives in water of around 26-32 C depending on season; the water is very soft and most often very noticeably acidic. Sexually mature males of Ancistrus dolichopterus can develop a powerful "antler", which is not typical and which often has multiple branched tentacles at its end. A special characteristic of the species furthermore is that even the females show unusually numerous, pronounced tentacles. Whereas females of other Ancistrus species mostly have only few short tentacles along the edge of the snout, the L183 females often also have somewhat longer and even branched outgrowths of skin at the front of the head, because of which the differentiation of sexes just before sexual maturity, which in many Ancistrus species is easily possible, is made very difficult in this species. The A. dolichopterus, which at the moment are always shipped from Manaus, are as a rule not more than 10-12 cm long and often already sexually mature. In the wild however they can grow significantly bigger and reach lengths up to an unbelievable 25-30 cm. So far I have only once set eyes on such big fish. What was noticeable with these fish was that even at this size they were still just as attractively marked as juvenile specimens can be. The care of A. dolichopterus demands great attention from the outset, as the newly imported fish are still very frail. Once they are acclimatized, the fish can be kept without any problem in harder water. Soft water is admittedly best with acidic pH in the region of 5.0 - 6.5, which one should give to the fish in any case for breeding. In this respect, this species is significantly more demanding than the other three, whose breeding is still possible at a somewhat higher pH. In the first few weeks of life the young fish have really very few spots and a vertical white seam on the tail fin which disappears shortly thereafter.
Ancistrus hoplogenys or L059 The catfish L059 was discovered by Kilian, Ludwig and a few collectors from the firm Tropicarium Para (Belem) in the summer of 1989 in a small tributary of the Rio Guama in the vicinity of the village Ourem. The hunters described this place of discovery as a smallish quite flat clear water river, in which the fish preferred to attached themselves to submerged wood, for example the wooden supports of a road bridge. The firm Transfish (Planegg) succeeded several times in importing fish of this species to Germany and in the meantime Werner (Transfish) has been able to breed A. hoplogenys in the aquarium. This bristlenose is the rarest and at the same time the most sought after species of this group and it is to be hoped that it can be maintained though breeding since new imports are hardly to be expected. Regarding the distribution of the white spots, Ancistrus hoplogenys is particularly similar to the other species described here. However the young of this species show a strongly red brown portion of the fins in the form of round flecks as well as larger areas, especially on the rim of the fin. With increasing age these red parts die away more and more. Even the white fin borders become narrower and narrower and finally disappear completely. The final size of this species can lie between 16-18cm. Perhaps it would be larger in the wild. The dorsal fin of this species has only 7 soft rays.
Ancistrus sp. (L 71/ L 181/ L 249) - The Spotted Bristlenose In her review of the genus Ancistrus which admittedly only exists so far as an unpublished doctoral thesis, Fisch-Muller regards this species as identical to Ancistrus dolichopterus. According to Fisch-Muller A. dolichopterus has a gigantic area of distribution in the Amazon. As for of the specimens examined by her from the Rio Trombetas, the Rio Tapajos, the Rio Tefe and the Rio Madeira (possibly L 292), it is certainly not a case of A. dolichopterus in the narrower sense, which as already mentioned, can be proved in other ways than just from differences in the number of dorsal fin rays. In adulthood the species can also be distinguished from A. dolichopterus simply by its colour, since at 4cm length the fish already begins to lose first the white seam of the dorsal fin then a little later also the seam on the tail fin. Finally they also have the dots on the body which turn out to be marginally finer than in A. dolichopterus. However, quite young specimens show an almost identical colouring to this species at first, even the white strip at the base of the caudal is apparent in the first weeks of life and does not disappear until later. The spotted bristlenose belongs to the most highly recommended of the more beautiful of the Ancistrus species, since the species is really unproblematic in its care. The fish breed in whatever suitable breeding caves are available mostly without any lowering of the pH level and can be really quite productive. The rearing of the young is no problem, but more on that in the last section of this report.
Ancistrus sp. (L088) - The black bristlenose In the meantime I am quite sure that the Ancistrus sp. "blue eyes" and Ancistrus sp. "black" pictured by Seidel & Evers (2005), which were both imported from Manaus, are identical to L088. Though a verbal statement from Wilhelm (see Evers and Seidel) we know that L088 lives for example in the Rio Demini,a tributary of the middle of the Rio Negro near Barcelos. In this clear water river however he could have detected this species in the upper reaches where it is at home in very soft acidic waters of about 26-29 C. How much further the distribution of this Ancistrus reaches is so far unknown. The Rio Demini is the main catchment area of catfish in the Rio Negro river system and Loricariids like Pseudacanthicus sp. (L114), Hypancistrus sp. (L136) and Panaque sp. (LDA001/L169) - to name but a few - are found, as well as Ancistrus dolichopterus *syntop* to L088. For this reason it is always a possibility with new imports of L088, that this species at least in adult colours, is comparatively plain and therefore might not be of the variety the 'catcher' would have preferred. The L088s I kept had a total length of 11-12 cm and were at that size fully sexually mature. However it is entirely possible that this species could grow significantly larger in the wild. Within a short time of having them, I succeeded in breeding them without great deal of effort. I kept the fish along with a few other catfish in a 200 litre tank which was filled with my own mix of tap water and reverse osmosis water, which I use for the breeding of other species I have sold. The pH was in the region of neutral. Since I had not reckoned on success so soon I can't say a lot about brood care, spawning and egg size. I was once surprised by a group of white banded young who had come out to eat and, when they were disturbed, darted quickly back to their hiding places. The young L088s as with all representatives of this group have at first a white border to the dorsal and caudal fins. The white spots, though, are not so numerous and the young does not have the white band at the base of the tail fin. At a length of 4-5 cm the spots have almost completely disappeared and at that stage only remnants of the white fin seams are visible.
Breeding A high occurrence of germs can be fought in various ways. The most effective method is regular changes of water; the more often you manage to do this the better the fry thrive. We know from experience that White seam bristlenose juveniles get on well with a 50 % water change once a week in a tank which is not too small. Also a lowering of pH in the breeding tank will naturally limit the number of germs, only I have noticed in my experience that there is no point is doing this when breeding of armoured catfish in aquarium conditions. For this reason I always acclimatize young fish as soon as possible to pH neutral water of medium hardness, even if, for purposes of successful breeding of certain species, I have at first had to use soft acidic water. Under conditions similar to the wild (soft, acidic water) you have the following problems. The fry of algae eating armoured catfish need a lot of food, almost constantly. In order to make sure they are getting enough food they are usually given more than they actually eat. Unfortunately most snails, which would otherwise be put in to polish off the left over food, cannot survive in calcium poor water, and so food is constantly rotting and causing pollution of the water that we simply cannot allow in the case of these sensitive fry. On the other hand even the fry of soft water catfish generally do very well in somewhat harder water. They don't absolutely need this lower pH but they do need the relatively germ free environment which have to try to provide for them by whatever means, and we must try to achieve this by frequent water changes. Furthermore we can of course in certain conditions keep the germ level low and extend the interval between water changes by adding a UV-water clearer. The frequently expressed doubt, that fish bred in such a way should later have problems with their immune defences in normal (high germ) conditions is completely unfounded, since by the addition of a UV water clearer the water is not made sterile and is never even as low in germs as the fish would be used to in their natural home. If you have got the knack for these fish and are successful in breeding them, they can even be quite productive. The reward for a breeder is a fairly certain market, since the demand for unusual and prettily coloured catfish is still high. So you would not be left with the breeders worst fear, namely that he might be stuck with his own product. There is further information on this species on the Cat-eLog page. Hits: 9113 |
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