Figure 1: L134

The sucker mouth catfish family (Loricariidae) is surely one of the most morphologically varied families of fish. With more than 70 different genera and over 600 described species it is the largest family of Neotropical catfish, only exceeded in number of species by the families Characidae (Characins), Cichlidae (Cichlids) and Cyprinidae (Cyprinids). In contrast however to the widespread distribution of these fish families, sucker mouth catfish are entirely limited to Central and South America.

Figure 2: L025

It is evident that within the confines of one lecture it's almost impossible to discuss this family in its entirety. Because of this I have selected one group from the large family of sucker mouth catfish on which to speak. Using the latest taxonomic status, recognized by most scientists, Loricariids can be divided into the following five subfamilies; Ancistrinae ( Ancistrus relatives), Hypoptopomatinae (dwarf plecos), Hypostominae ("common" plecos), Loricariinae (whiptails) and Neoplecostominae, the latter being largely unknown to aquarists.

Editors Note:
The aforementioned common names are the generally accepted English common names. The literal translations from German are rather interesting and are certainly worth noting here. Hypoptopomatinae are Ohrgitter-Harnischwelse (ear mesh pleco - referring to their perforated head bones), Hypostominae are Schilderwelse (armour plated catfish, but specifically flat plated armour that also covers the arms) and Loricariinae - Hexen, Nadel & Störwelse (witches, needle and sturgeon catfish). Hexen / Witch Catfish, what a great name! Plecos in general are known as Harnischwelse, which literally means horny catfish! At first I thought of this in the sense of rough textured like a pineapple skin. After further research however the precise meaning was found to be mail armour, so plecos are more sensibly called mailed catfish. Mind you, katzenfisch (catfish) sounds strange to German ears.

Figure 3: L267

Thus the Loricariids from the Ancistrine group are the focus of this article, and specifically, the reproduction of these species. I've been working with them for some years now. Firstly, I would like to explain how one defines a representative of the subfamily Ancistrinae in the first instance.

Figure 4: Barbed hooks of Ancistrus sp. L120/L182

The name of the subfamily is derived from the Greek "agchistron" or "agkhistron" and essentially means "barbed hook". This is also the discerning feature of Ancistrine plecos. The representatives of this sub family possess an evertible area between their gill covers, (Interoperculum), on which can usually be found spines or tentacles (Odontodes). With some members of the sub-family these interopercular odontodes are very strong and curved, with others long, smooth and thin. Aquarists who keep such fish, occasionally encounter these hooks the hard way! When netting plecos with these anatomical features, the animals invert their interopercular hooks and invariably remain hanging in the net with their hooks caught.

Figure 5: Hypancistrus zebra in the spawning site

The representatives of the sub family Ancistrinae are also without exception cave breeders. The male will guard a clutch of eggs which typically comprises relatively few eggs of 2.5 - 5 mm in diameter and whitish or yellow in colour. The male assumes responsibility for these eggs up until when the young fish hatch. These offspring are not immediately independent however. The larvae of most types initially possess an enormous yolk sac which sustains them for some days. Up to then they remain with the male in the brood crevice.

Figure 6: Head of Typical Male Ancistrus sp.

To have any chance of breeding success at all, firstly, animals of both sexes must be present. You would think that one could easily buy a small group and therefore have, in all probability, the presence of both sexes. However, since some plecos are quite expensive, the average aquarist won't usually be able to afford any more than 2-3 animals and thus a great importance is attached to the recognition of the sexes. As Ancistrus species mature, numerous tentacles grow on the head of the male Ancistrus. Most female Ancistrus possess only small extensions around the edge of the lip. Now, although the Ancistrus species are simple to sex, determining the sex of other members of the Ancistrinae sub-family is unfortunately not that easy.

Figure 7: Male L66 (Frontal view)

With all representatives of every other genus, no head tentacles are available to allow clear distinction between male and female. However there are numerous other secondary forms of sexual dimorphism. Odontodal growth on these fish does however point to differences between the sexes. Investigation of these odontodal growths on the body surface reveals calcified conical structures, which strongly resemble comb-like teeth. The odontodal growths can be found on the bone plates of the entire body, on all fin rays and on the outside surface of the head bones. The surface thus feels like the skin of a shark; very rough indeed. The development of such rugose growth differs from species to species.

Figure 8: Strong Interopercular Odontodes on L66

In many Loricariids , extended odontodal growths are found on the head area, on the fin rays, the back and rear body. The males of certain species display an intensified development of such odontodes during the breeding season. Particularly, the interopercular odontodes are longer on most adult males than those of the females. With some species large bundles of such spines project out from the lower front gill cover. We can see here the head of a full grown male L66, which displays very strong interopercular odontodes.

Figure 9: Male Dekeyseria scaphirhynchus

Also on the thickened front edge of the pectoral spine are numerous forward pointing denticles, which vary in strength from species to species and frequently between sexes. This male Dekeyseria scaphirhynchus from the Rio Tefé in Brazil, photographed immediately after being caught, had extraordinarily strong pectoral fin odontodal growth. Equally large females however, were found to have no hint of growth on this spine.

Figure 10: Peckoltia sp., "hairy" male and "bald" female

In some genus (e.g. Peckoltia, Panaque and Hypancistrus) further denticles on the rear-body bone scutes can be found on nuptial males. This pair of a still unidentified species of Peckoltia from North East Brazil clearly display sexual dimorphism. Rarely however, do Peckoltia and Panaque species show this level of odontodal growth on the back portion of the body. Most males exhibit many shorter, hair-fine denticles which can be seen if one looks at them from the correct angle, essentially so that the light is reflected by them.

Figure 11: Male Oareiorhaphis bahiana

There are some quite extreme examples of secondary sexual dimorphism. By way of further example a species which even a novice would be able to sex is Pareiorhaphis bahiana. With this catfish the sides of the males head are widened and endowed with strong spines. Additionally the other leading fin ray bristles of the males are extremely obvious. If it were always so simple!

Figure 12: Genital papilla of female L002

For those plecos which are not identifiable by the previous techniques, the aquarist must finally take a magnifying glass to hand and examine the sex organs of the animals. The genital papilla of many females is, as shown here, round and blunt, those of the males by comparison are smaller and pointed.

Figure 13: Breeding tank

Given that we have selected suitable animals for reproduction, then we must consider the next important: the selection and decoration of the breeding tank. Simply put: the larger the better. Some species have already bred in smaller aquaria starting from a size of 60 litres. Surely however the prospect of breeding success increases (ultimately including the larger species), with the tank size. The decoration can be kept quite spartan. Some flat stones arranged in layers and wood should be available however as minimum decoration. Substrate and aquatic plants can be omitted if necessary. In addition, the cosmetic appeal of such a tank is important particularly since the inclusion of both substrate and plants surely provides for more stable water conditions.

Figure 14: Water system

And so we come to the water. The reproduction of Ancistrine plecos succeeds with most species simply in medium hard, slightly alkaline tap water. Soft water (it does not have to be acidified) is not necessarily required. It is my experience that the animals grow up more evenly in soft water and I've not had many losses in raising the fish this way after adopting this approach. It should also be considered that some "hard nuts" are perhaps to crack (be induced to spawn) in soft water. For some black water inhabitants, for example many Rio Negro types, mechanically purified soft water is recommended. The aquarist must decide for themselves whether to produce soft water, as seen here, through a water system or through a full demineralizer. In some areas one can perhaps fall back on rain or spring water.

Figure 15: Filtration

A much larger importance should be applied to filtration as opposed to water chemistry. The whole shape of a pleco is adapted to a life in flowing waters. Therefore it is advantageous to provide via strong filtration in the aquarium a certain current. How much water movement one needs for the reproduction of a certain species, cannot be forecast that easily. This is different from species to species and perhaps even from animal to animal. By way of example, for two years in succession, my L66 began spawning only after I increased the filtration rate in both 120x50x30 cm breeding tanks by an additional 600 litres water per hour. This increased the water through flow by another third.

Figure 16: Teeth of Peckoltia sp.

Reproduction can only be induced with well conditioned fish. Therefore when considering breeding, it is crucial to pay special attention to correct nutrition. The number, form and arrangement of teeth inform us of the nutritional requirements of these animals. Many plecos nourish themselves in nature by eating algae or Periphyton - [Aquatic organisms, such as certain algae, that live attached to rocks or other surfaces. From Greek, 'phuein' to grow-Ed] , which they scrape off from stones or wood with their series of comb-like teeth. Aquarists are particularly fond of these species, since they "clean" the furnishings and walls of the aquarium and remove the unsightly algae. Once clean however, sufficient algal growth to sustain a group is unlikely to develop. In order to fulfil the vegetarian requirements of these animals, supplemental food must be offered in the form of vegetables or "green" tablets. But our fish are not purely vegetarians, commonly it is the aquarist that simply assumes this.

Figure 17: Teeth of Leporacanthicus sp.

The formula "sucker mouth catfish = good algae eater" does not hold true. There are a whole set of plecos, for example this galaxy pleco, Leporacanthicus galaxias [The German common name is trunk tooth catfish - Ed], which possess a sucker mouth but it's not suitable however for scraping off algae. These species have a greatly reduced array of teeth specialized towards eating quite different fodder namely detritus, insect larvae or molluscs.

Figure 18: Lasiancistrus heteracanthus eggs

As I have already stated, Ancistrine plecos are cave breeders. In nature the animals select themselves a hole or hollow column in the wood or rock they live on as spawning sites. Here a scooped out log was used. The large clutch of eggs which can be seen belongs to a Lasiancistrus heteracanthus from the Rio San Alejandro in east Peru. The guardian male dropped off when raising the log.

Figure 19: Various spawning holes

In the aquarium these animals happily adopt alternative spawning sites or caves. The mandatory coconut bowl or up-turned flower pot is only sufficient for a few modest, easily satisfied species. In the trade there are already various solutions; imitation logs made from clay or ceramic(s) are suitable. Since however a spawning cave should be adapted to the size of the potential parents, it is advisable to make these yourself from clay or slate. Self crafted caves can be baked in a pottery kiln relatively cheaply. Alternatively the fish will readily accept caves made of roof slate which can be cut with a friction disk and then stuck together with silicone (preferably black).

Figure 20: Cave with lateral entrance

Some plecos prefer caves with a lateral entrance. These should be built quite long but, erring on the side of caution, possess a large opening so that the fish can enter and leave comfortably. It is important that aquarists utilizing these caves ensure that the cave supplied "grows" with the fish. Otherwise you may find that once the fish is inside, it cannot leave again of its own accord!

Figure 21: Holes in the embankment

Until some years ago it was assumed that caves in the embankment are only used by certain suckermouth catfish of the sub-family Hypostominae as spawning sites. It is now known however this is also applicable to certain Ancistrine catfish. For example Leporacanthicus triactis reproduces in tunnels dug in the embankment. Since it is almost impossible within the confines of an aquarium to reproduce this type of environment for these fish to lay their eggs in, the aquarist would need to bring in clay tubes.

Figure 22: Ancistrus sp. (L110 / L157)

The genus Ancistrus, with approximately 55 described species, is the largest within the sub-family Ancistrinae. The many tentacle like growths on the front and sides of the males head are typical of this genus, we find no other with this feature. Females growths are either missing completely or are limited to the edges of the head. Although the name antenna catfish was actually already assigned to another South American family (Pimelodidae), the Ancistrus species are so called because of the adult males head decoration. [This dual use of common names only occurs in German, the English common name, Bristlenose catfish, has no such duality and we shall use it in future, it should be noted that the German common name is blue antenna catfish, even for the albino varieties. -Ed].

Figure 23: Ancistrus sp.

Without exact discovery site information, only a handful of species are sufficiently unique to correctly identify. In addition the species designations used in common literature are extremely doubtful. The species shown here is commonly called the bristlenose catfish or Ancistrus dolichopterus. It can be assumed that under this identification different but similar species are mixed up and this has surely already lead to confusion. Furthermore, most literature describes wild caught males usually with head decoration; over many generations of aquarium breeding, these identifying features diminish to the point where they are hardly present at all.

Figure 24: Ancistrus sp. with clutch of eggs

One cannot speak of more easily achieved breeding success than with these catfish. In an aquarium, in which suitable refuge for the male exists, spawning is actually hard to prevent! Bristlenose catfish aren't remotely discriminating with their selection of a brood cave; a clay flower pot or half a coconut shell (from which a small entrance/exit hole is broken) are completely sufficient. Up to 200 yellow eggs are laid by the female and are stuck together like a bunch of grapes within the spawning cave. The male guards the clutch of eggs alone and continues with this duty for some time even once the fry hatch. Only after consuming the yolk sacs will the youngsters permanently leave the protective dwelling and distribute themselves throughout the entire aquarium. Even in a heavily stocked community tank some young fish will come through. Despite the many enemies in such an environment and without further vigilance from the male nurse, the juveniles nourish themselves on algae and scraps of food. Those more concerned with their new charges welfare can siphon off the fry before they leave the spawning cave and maintain them in a species tank.

Figure 25: Albino Ancistrus sp.

With Bristlenose, as with many other very frequently bred aquarium fish, it was only a matter of the time before the first mutations appear. In keeping with this trend, the first colour variation available was an albino. Presently we know two different albino bristlenose catfish forms, a purely yellowish form and a yellow with white form (as shown here). This further indicates that under the common banner of bristlenose catfish several similar Ancistrus species are involved. Anyone crossing these two albinos together is in for a nasty shock: all the offspring are normally coloured! Otherwise the albinos are just as easily bred as the wild form.

Figure 26: Marbled Ancistrus sp.

Also a marbled variation of the bristlenose catfish has been bred. [This varieties name translates as the Piebald Ancistrus from German - Ed]. With this colour form the young fish are quite attractively coloured. They are almost equal parts brown and yellow-orange but, unfortunately, loose this juvenile attractiveness and become steadily darker with age.

Figure 27: Black-eyed Ancistrus (L144)

Although there is also a yellow Ancistrus with black eyes from Paraguay, there additionally exists another black-eyed version of bristlenose which is very pretty. The animals are substantially more attractively colored than the albino bristlenose. Their background colouration can be orange yellow in full (as depicted here). Due to the vast number being bred in captivity, further mutations will probably appear in the future. Opinion is divided regarding the sense and purpose of such selective breeding. As long as the vitality of the animals is not limited by such practice, one can surely tolerate this. One has to hope that "veil-tail Ancistrus" remain saved from us.

Figure 28: Ancistrus claro (LDA8)

I would like to demonstrate the breeding biology of Ancistrus species using Ancistrus sp. (LDA8) on the basis that it is a very pretty small species. In March 1993 under the moniker "LDA8" an Ancistrus species was presented, which due to their attractive patterning and the small full-grown size seemed very interesting indeed to the aquarist. [This species was later described as Ancistrus claro - Ed]. The females achieve a full grown length of around 8 cm with the males remaining somewhat smaller. Depending upon mood the colouring of the reticulated pattern can vary from quite inconspicuous light brown to a stunning, almost gold, yellow. It originates from the Matto Grosso area in Brazil although the exact discovery site remains unknown. One does not need enormous aquaria for the maintenance and spawning of this species. A 100 litre tank is approximately sufficient. Breeding is also possible in tap water.

Figure 29: Ancistrus claro eggs

Ancistrus eggs are laid in a firmly sticking cluster that closely resembles a bunch of grapes. They are usually yellowish and relatively large. It appears that smaller species (such as LDA8) produce substantially larger eggs than the bigger species. The number of eggs, by contrast, is extremely small. Typically LDA8 produces a clutch of only 25-30 eggs, while the Ancistrine giants can produce several hundred eggs. Fresh water is constantly passed over the clutch of eggs by the father who diligently wafts them with a pair of his fins. Dead eggs are also removed from the clutch.

Figure 30: Ancistrus claro fry with yolk sac

After 5 to 7 days the young fish hatch and initially possess an enormous yolk sac. Since they would be somewhat unprotected from the outside worlds ever-present predators, the fry remain safely inside the cave with their father and consume their yolk sacs. The Male exhibits an unusually high degree of parental care.

Figure 31: Three day old Ancistrus claro

Three days later the yolk sac is already clearly smaller. The fry has also greatly increased in length. The body shows now translucent light brown pigmentation. At this age the young fish sit together in a close group, these wriggling bundles of energy are constantly in motion.

Figure 32: One week old Ancistrus claro

After a week, at the latest, the yolk sac is entirely consumed and the young fish leaves the cave. From now on they are on their own and immediately strike out on the search for food. They can be brought on with smaller live food like brine shrimp nauplii, dry and green foods. Continuous attention must be paid to maintaining good water quality, failure to do so will result in high loses and a poor growth rate.

Figure 33: Raising tank for fry

Hanging fry tanks (with holes or slats in the sides) are substantially better than moving the fry to a separate aquarium. Shown here is a manufactured glass container with gauze side panels. These have the advantage that water can flow in from outside, but live food can't escape. If the aquarist raises the fry in an aquarium by themselves then either the danger exists that they do not find sufficient food (since the food is lightly distributed around the entire tank), or the aquarist may overfeed and spoil the water. In hanging boxes, which are best placed in large and well filtered aquariums, the aquarist can achieve both concentrated feeding and good water quality.

Figure 34: Young fish eating

Ancistrus youngsters can be fed tablets, brineshrimp nauplii and certain vegetables, namely blanched lettuce, spinach or brussels sprouts, the later two being defrosted from frozen. Unprepared vegetables are usually somewhat hard for the young fish and cannot be eaten until after a couple of days. The excrement of the young fish should be siphoned off regularly (1 or 2 times per day). Certain snails will eliminate surplus food scraps. Generally, feeding should be frequent but sparse (particularly if feeding brineshrimp).

Figure 35: Larger juvenile

Once they reach a size of approximately 2-2.5 cm the young fish can be moved into more spacious surroundings. They are now substantially stronger and this in turn means less danger that careful feeding will immediately cause starvation. The fish also have much more swimming space. In larger, heavily filtered aquaria, (which in terms of water quality are naturally more stable), water conditions are considerably more difficult to control than before. One must proceed carefully, especially with regard to feeding. Some tablets disintegrate and badly cloud the water. Most tablets with high plankton or Spirulina algae by comparison decompose substantially more slowly. They don't affect the water so strongly and can as be used long-term food.

Figure 36: Ancistrus sp. L089

At first glance one could think Ancistrus sp. (L89), was in fact, the "common" bristlenose. On closer inspection however some differences are noticeable. The animals possess a reddish fin seam, which is preserved as the fish mature to adulthood. Since the patterning of this Ancistrus is considerably higher contrast, it is called also network bristlenose or L89. Unfortunately the catfish doesn't always display its striking colouring and therefore can be mistaken with the "common" bristlenose.

Figure 37: Juvenile L089

The juvenile L89 are even more intensively coloured than the older animals, the network colouration pattern stands out particularly clearly. The species is just as easily bred as the "common Ancistrus". It can be considered a genuine alternative.

Figure 38: Ancistrus sp. (L183)

For some years now, the White seam or Spotted Bristlenose has been well-known to aquarists. It is imported regularly from the Rio Negro area into Brazil to us. As a black water inhabitant, one should maintain it in not too hard water. The first requirement for a successful spawning of this species is soft water. Also the species seems to need somewhat warmer water than most. Under favorable conditions spawning is easily achieved. After just a few weeks the young fish already exhibit the very attractive colouration of their parents and are therefore very popular. [Ed - L183 is now widely accepted to be Ancistrus dolichopterus]

Figure 39: Ancistrus sp. (L107 / L184)

Easily one of the most beautiful bristlenose, this is another species originating from the Rio Negro. I has been assigned two equivalent L-numbers (L107 and L184). Initially the juveniles possess an upper and lower caudal filament that is sometimes coloured white. This is very unusual amongst bristlenoses. The size of these white marks can greatly vary from individual to individual. The females of this species lay only a few but relatively very large eggs. Successful spawning was only achieved intermittently. For it, in any case, soft water is necessary.

Figure 40: Ancistrus sp. L120/L182

One needs large tanks, if one wants to maintain a bristlenose of such caliber. L120/L182 (from the Rio Branco in north Brazil) rarely reaches the 25 cm length that it can be found growing to in the wild. The males display unusually large head "bristles" around and during the spawning season. The longest bristles are often "branched" several times. Outside of the spawning season these can regress somewhat. This is the species I mentioned earlier whose clutches of eggs can consist of several hundred eggs. Although this species reproduced several times in caves fashioned from roof slate, these had to be adapted to the larger size of the animals. Spawning succeeds in tap water. Soft water is however more favorable for raising the fry as it ensures more even development.

Figure 41: Juvenile Ancistrus sp. L120/L182

One of the most pleasing aspects of raising tank bred fish is that the aquarist gets to view the fish at all stages of its development. One never knows, following the first successful spawning of a species, how the juveniles will look. Probably no one would have assumed that the fish pictured here is the same animal as the adult shown previously (Figure 40). Again it is unfortunate that these animals lose the attractive rusty fin seams with increasing age.

Figure 42: Ancistrus sp. 'Portel'

This species of Ancistrus illustrates that the spawning of certain species can be very unproductive. The fish originates from Brazil and initially appeared in the trade under the designation Ancistrus sp. "starry night" and is now known as Ancistrus sp. `Portel`. It's a pretty dwarf species of only about 8 cm total length, which can be bred relatively simply in tap water. Now, where's the catch I hear you ask? In two separate spawnings the clutches of eggs consisted in both cases of approximately 5 enormous eggs, from these hatched 7 fry. The fry were also very large and further raising was straightforward.

Figure 43: Ancistrus ranunculus

It's probably true to say that all Ancistrus species will reproduce in the aquarium if one offers suitable conditions to them. Well, that and a lot of patience on the part of the aquarist. Some fish will not spawn despite apparent ideal conditions, in this case one should try from time to time to change certain conditions. Often transferring into another aquarium helps or a decrease of the electrical conductivity of the water, an additional flow pump or a rise in temperature. The Ancistrus ranunculus shown here, which are identified by the very broad and flat body, were induced to spawn in this manner.

Figure 44: Peckoltia vittata (L015)

The representatives of the genus Peckoltia strongly resemble the Ancistrus species in their requirements for maintenance. Many Peckoltia species are coloured and patterned even more attractively than most fish covered so far. There size also makes them especially suitable for keeping in the aquarium. Captive spawning is possible, as sporadic reports show. The Peckoltia vittata (L015) shown here from the Rio Xingu has apparently not been bred in captivity as yet. Sexing most species is relatively easy. Sexually mature males display numerous odontodes up to 3 mm long on the back half of the fishes body. These are substantially shorter on the females. Unfortunately all species do not exhibit such sexual dimorphism.

Figure 45: Peckoltia sp.

This Peckoltia species from the Tocantins river in the northeast of Brazil reproduces quite readily in the aquarium. It only achieves a length of approximately 10 cm and was spawned in a small aquarium. Given that you're tap water isn't that hard, then no modification of the water chemistry is necessary for this species. In a suitable spawning site (e.g. a clay cave) about 30-40 fairly large yellow eggs are stored. Immediately after hatching the fry are already very large indeed and sport a large (approx. 5 mm) yolk sac, they are however completely devoid of pigment.

Figure 46: Juvenile Peckoltia sp.

After approximately 12 days they have exhausted the yolk sacs contents and leave their cave and yolk sac behind. Raising young fish presents no difficulties and is very similar to the approach adopted for bristlenose catfish. They similarly have quite strong teeth and therefore should be presented with vegetable food. Young Peckoltia possess a very regular and high-contrast patterning. Since their price is usually affordable and they can be kept in smaller tanks, at present quite a few aquarists are occupied with these animals. Further spawning success with Peckoltia and similar species are to be expected in the future.

Figure 47: Hypancistrus zebra

Probably the most exciting, eye-catching discovery of the last few years was the zebra pleco (L46), this species was available to aquarists for some time before being assigned the scientific name of Hypancistrus zebra. This species has all the prerequisites of an ideal aquarium fish. It's endowed with an extremely attractive colouration, has a small final size (approximately 10 cm length) and is relatively easy to breed. The zebra pleco originates like many other "L" number catfish from the Rio Xingu in Brazil. When maintaining this species in the aquarium one should consider that in the Rio Xingu quite high temperatures of 30 - 35 °C prevail. This species has no particular requirements in terms of water chemistry.

Figure 48: Pair of Hypancistrus zebra

The sex differences are not as prominent with Hypancistrus zebra as in comparision with, for example, a bristlenose. Nevertheless one can determine the sex fairly accuarately with adult specimens. Males, like one shown here on the left, have a substantially broader head shape and longer interopercular odontodes which are thicker than the females. Females usually remain aroundl 1-2 centimeters smaller than their male partners. The female shown (on the right) displays quite well the narrower and more pointed head shape. Also the males can occasionally look egg bound and thus this is not a safe distingushing feature. I assume that the males starve themselves for the time in which they care for the clutch of eggs and live solely off fat.

Figure 49: Mouth of L046

This view of the mouth betrays the way of life of these animals. Since it has a fairly small suckermouth, it is to be assumed that this is not an inhabitant of fast flowing waters. The reduced set of teeth of the zebra pleco also shows that it is not a good algae eater. And indeed this catfish eats, almost exclusively, carnivorous food in the aquarium. If one offers optimal conditions to the animals, then spawning is not always that difficult. Actually there are only a few factors which one must consider in order to successfully achive this. These are: good water quality, water temperature of at least 27°C, balanced nutrition and a suitable spawning cave.

Figure 50: Six day old H. zebra eggs

The actual laying of eggs is usually difficult to watch, because the male almost completely obscures the inside of the cave with his body. The zebra pleco is quite unproductive laying only a few enormous eggs. The clutch usually consists of 7-12 eggs, which have a diameter of 4 - 5 mm. They are whitish coloured and stick very firmly together. Briefly before hatching, which depending upon temperature can take place after 6-7 days, parts of the fry can already be made out through the egg shell. The eyes in particular and some blood vessels stand out against the remaining body. One can even see the heart beating clearly.

Figure 51: H. zebra fry

And finally we are here! A still completely unpigmented fry with an enormous white yolk sac hatches out of the egg. As you can see, this is a large strain on the fry. It cannot initially free itself completely of the egg shell. Eventually this is achieved and the fry immediately attempt to attach themselves (using their still very small suckermouth) to a flat surface. This presents another great difficulty for the young fish due to the great mass of the cumbersome yolk sac still in tow. At this age the young fish rarely stop wagging their tails.

Figure 52: Captive bred juvenile

The yolk sac disappears completely after 11-14 days depending upon water temperature. The young fish are now miniature replicas of their parents. Like the Ancistrus species they now leave the spawning cave in search of food. Raising Hypancistrus juveniles is straightforward. They can be raised, loss-free, on Artemia nauplii and most dry foods. A note of caution however, don't use a plastic or plexiglass container for raising these fish since they scratch the sides so strongly (with their few, but large, teeth) that after just a short time you can't see in.

Figure 53: L066

There are other plecos with reduced teeth on their jaw related to the zebra pleco that are as easy to breed. One of the prettiest of these is L066 from the Rio Tocantins or Rio Xingu river in North East Brazil. The species attains a somewhat larger maximum length (14 cm) than the zebra pleco. In youth it is a very attractive fish with a high-contrast pattern. Unfortunately, as the fish ages, the pattern blurs. The adult males are inclined to be very dark and posses strengthened bundles of interopercular odontodes and fine, hair-like denticles on the entire back half of their body.

Figure 54: L066 - Pair in Spawning Cave

Again it is possible to spawn this species in clay or slate caves. Here you can see a couple with the eggs in a cave made from even roof slate. I could trigger L66 spawning in two sequential years by additional installation of a further flow pump, the output of which was aligned directly to the cave opening. Again in both cases the first clutch of eggs did not develop correctly, I analyze this is a characteristic of too many eggs being laid. Something like this is well known from breeding Characoidei. As to water requirements, the aquarist has little to do since all subsequent clutches of eggs developed normally in tap water.

Figure 55: Eggs of L066 and L046

The clutch of L66 eggs, which can be seen on the right, is very much larger than the clutch of eggs of Hypancistrus zebra (left). On the one hand we have a few 4.5 - 5 mm in diameter zebra pleco eggs and on the other larger eggs produced in greater numbers by L66. Clutches of L66 eggs can contain up to 50 eggs. Again in contrast the male L66 is a much better nurse than the zebra pleco. The development of eggs and larvae takes almost exactly the same amount of time with both species.

Figure 56: Young L066

L66 youngsters grow substantially faster than young zebra plecos, the later making the aquarist wait an age until they attain a size at which they can be passed on to another enthusiast. Raising L66 is problem-free given a diet of tablet food and small live food. The young fish fare considerably better in soft water as opposed to tap water.

Figure 57: L073

Another frequent import from the Rio Tocantins / Rio Do Pará tributary in North East Brazil, is the "Angelicus Peckoltia". This is a trade name and the fish is assigned several L-numbers (L4, L5, L28 and L73). The figure of L73 in DATZ ("Die Aquarien und Terrarienzeitschrift" a monthly German publication) corresponds to the adult colouration of the species, while the other l-numbers are stages of juvenile development. The angelicus is another relatively easy-to-breed species. Females of this species lay up to 50 fairly large eggs at a time.

The young fish have fewer yet larger spots than the adults. Rasing these fish doesn't present any big problem, but they do have a single, unpleasant, characteristic. Although they actually reject vegetable food offered to them, they use their large teeth to utterly destroy almost all aquatic plants which are in the "grow-out" tank. All that remains are perforated leaves. This behavior is probably a by-product of the search for food and I do not believe that this fish is an active vegetarian.

Figure 59: Pseudacanthicus leopardus (L114)

Until fairly recently it was generally thought that the larger plecos wouldn't reproduce under aquarium conditions because the aquarist could not create living conditions appropriate to their large full grown size. Mind you, it is also know that many species do not attain their full grown natural length in the aquarium. Additionally these plecos become sexually mature extremely early. The leopard pleco, Pseudacanthicus leopardus (L114) falls into this category and is sexually mature at length of approximately 20 cm. (The German common name is "leopard-kaktuswels" or literally, leopard cactus catfish which, if you ask me, is a better, descriptively rich common name -Ed)

Figure 60: L114 in cave

For spawning sites, similar caves should be offered as are used for the other Ancistrine species. Naturally, these caves should be accordingly larger. Caves with a lateral entrance are gladly adopted. Obviously, over time, these fish will grow and there is a danger that these fish occasionally upon entering such a cave do not come out again. Accordingly, one should substitute larger caves from time to time. Since this a Rio Negro inhabitant, soft water is advantageous for breeding.

Figure 61: L114 Juvenile

I observed that the 20 cm long adults laid around 100 large eggs, out of which initially colourless young fish with enormous yolk sacs hatched. Subsequently the young fish assumed this attractive black-and-white colouring. They were fed with tablets and Artemia nauplii. Unfortunately, due to an illness that ate away the tails of the young fish, all the brood perished. More sadly, the parents have yet to spawn again.

Figure 62: Acanthicus adonis

Even of the gargantuan Acanthicus species, which can achieve a length of one metre in nature, one hears from time to time something regarding reproduction. The Acanthicus adonis illustrated here has been induced to spawn in larger aquarium. You see, nothing is impossible.

Figure 63: Rio Tulumayo

Finally I would like to introduce to you the bulldog pleco group (In German these are called mountain plecos -Ed), which, in terms of reproduction, deviate a fair bit from the species covered thus far. This is connected to these fishes origin. The habitat of the many species of Chaetostoma are fast-flowing waters of the Andes region of South America. Sometimes these waters are even so rapid that one dare not stand in them despite a relatively flat water level. Due to their very strongly flattened body form and their enormous suckermouth, these catfish are well adapted to these extreme habitats. Waters of the Andes region are very rarely soft and acidic. Therefore tap water is ideally suited for the maintenance and spawning of most species.

Figure 64: Rio Tulumayo Riverbed

One can create an aquarium for bulldog plecos that marvelously recreates nature. Use the finest sand as substrate. Upon this some flat stones are placed one above the other. No excessively strong filtering is required for spawning Chaetostoma species, although one would assume this due to the habitats of these plecos. Increasing the oxygen content of the water by way of an air diffuser or airstone is however a very good idea. The temperature should be set depending upon the origin of the species but will typically be between 20 and 27°C.

Figure 65: Chaetostoma sp. "Rio Meta"

This diminutive Chaetostoma is well-known in the upper Rio Meta river in Colombia and has emerged in the trade under several diverse common names. These are probably the only species of Chaetostoma successfully bred in the aquarium so far. There are not strong signs of sexual dimorphism exhibited by these fish. The males have however a somewhat larger and broader head, slimmer ventral sides and disproportionately large pelvic fins. Perhaps the over-sized pelvic fins play a large role in the fertilization of the eggs. By inverting these over the clutch of eggs, they prevent the sperm cells being carried away too fast in the current.

Figure 66: Chaetostoma eggs

Spawning this pleco can be accomplished successfully in relatively small tanks. The males dig themselves a cave under stones or wood, which they inhabit even outwith the breeding time. To the cover of the cave by the female a clutch of eggs out existing up to 60 eggs is attached. The eggs are first yellowish and become ever darker in the course of their development. The young fish can already be seen clearly through the egg shell.

Figure 67: Chaetostoma fry

After approximately 7 days the young fish slip almost completely developed out of the egg. They possess only tracks of a yolk sacs and leave immediately the cave. With the types from cooler waters that is actually quite understandable. One can also with other fish always again to observe that the hatch of the young fish the later taken place and this then many further is developed, ever cool the water is. Already after short time the young fish begin to eat and can now with various drying -, from green and live food places be nourished. Raising bulldog plecos can present significant problems. Even half-grown fish are still relatively sensitive and often acknowledge carelessness with death. One obtains the best results raising the youngsters in large tanks with good filtration at cooler temperatures. Since growth is quite slow, the new generation needs almost 2 years to achieve sexual maturity.

Figure 68: L200

One could see from this lecture that various Ancistrine species of most different genus under favourable conditions in the aquarium can be bred. For a spawning success a suitable pair of animals, as roomy an aquarium as possible, strong filtering, frequent water changes, correct and varied feeding, are important with most species. And don't forget water temperature and suitable spawning caves. Then it should be possible to produce offspring from, as yet, "unspawned" plecos. Nevertheless, simply try it.