Lake "Maravi" (Malawi) first appeared on Portuguese maps as long ago as 1546. Maylandia crabro, the "bumblebee cichlid" of aquarists, is a cleanerfish. That is to say, in Lake Malawi it obtains much of its food by nibbling small parasitic crustaceans known as fish lice (Argulus) from the skin of Bagrus catfishes, which are much larger than it is. The cichlid's bright beelike coloration of yellow with chocolate-brown vertical bars may serve to "advertise" its cleaning services. The southern and western shores of Lake Malawi were extensively explored by David Livingstone. A lepidophage (LEP-id-o-fayj) is an organism that eats another animal's scales. Lepidophages have evolved independently at least four times among Lake Malawi's cichlids: two mbuna (Melanochromis lepidiadaptes and Genyochromis mento) and two "haps" (Corematodus spp. and Docimodus evelynae). The two Corematodus species and some Genyochromis are also aggressive mimics of their prey's coloration. Lake Malawi boasts an endemic genus and species of freshwater sponge, Malawispongia echinoides. This little colonial animal occurs nowhere else on earth. In a cichlid fauna replete with unusual dietary specializations, the two species of Docimodus surely have some of the strangest. With its short, wide, powerful jaws-- somewhat recalling those of a bolt-cutting tool-- D. johnstonii bites off and eats the fins of clariid catfishes. Its sister species, D. evelynae, bites pieces from the skin of these poor catfishes, as well as eating scales bitten from cichlids and cyprinids. The first fishes from Lake Nyassa (Lake Malawi) to reach Western science were collected by Dr. John Kirk, the naturalist with David Livingstone's second expedition (1858-1864). Kirk correctly observed, "The fishes of the lake are almost all of species peculiar [i.e., not found elsewhere]." These specimens, in the form of dried skins, were described in 1864 by Albert Günther at London's British Museum. Lake Malawi, in its water chemistry (notably, its total ion concentration, or alkalinity, and its resulting electrical conductivity), is intermediate between Lakes Victoria and Tanganyika, and much more similar to Lake Victoria. It is possible-- although not recommended-- to keep Victoria cichlids in the same aquarium as those from Lake Malawi. Tanganyika cichlids, however, should never be kept with those of Lake Malawi. Periphyton (PAIR-ih-fy-tun) is the term for algae that grow on higher aquatic plants. A few Lake Malawi cichlids have jaws and teeth specialized to exploit this specific food source, including the "hap" Hemitilapia oxyrhynchus and the mbuna Cyathochromis obliquidens. Otters can be seen fishing and playing in the water off rocky shores in Lake Malawi. There are two kinds: the Spotted Necked Otter, Lutra maculicollis, which is often seen during daylight hours, either singly or in small groups; and the more nocturnal Cape Clawless Otter, Aonyx capensis. Both otters are widely distributed in southern Africa. Strange as it seems, the commonest cichlid in Lake Malawi (Diplotaxodon limnothrissa) was unknown to science until 1994, when George Turner published its name and description. It is believed to have a population size of 1.5 billion adults at any one time. Moreover, Lethrinops turneri, the commonest cichlid in Lake Malombe (south of Lake Malawi), was only named in 2003. Some 850 million of this fish are caught each year. Question: How is Tilapia rendalli different from all other cichlid species found in Lake Malawi? Answer: T. rendalli is the only cichlid in the lake that guards its eggs and larvae on the substrate, instead of carrying them in the mother's mouth for protection. This tilapia is widely distributed in southern Africa. Epixylic (ep-ee-ZY-lik) algae are algae that grow on submerged wood. Only one Lake Malawi cichlid, the undescribed mbuna known as Pseudotropheus sp. "acei," is known to feed principally on this specific food source. P. "acei" live around waterlogged tree trunks and large branches that are washed into the lake in some places. An aggressive mimic is a predator that appears to be something else to capture prey. Superb examples from Malawi's cichlids: Corematodus shiranus mimics the silvery color and ragged vertical bars of shoaling tilapias; it swims among them and can get close enough to dart in and bite off mouthfuls of scales. Nimbochromis livingstonii, colored like a rotting fish, plays dead and eats small fishes attracted to its "carcass." With a vast surface area of 31,000 km² (12,000 mi²), Lake Malawi is the third-largest African lake, and ninth- or tenth-largest in the world. Its surface is 474 meters (1555 feet) above mean sea level, but its maximum depth of 704 meters (2310 feet) makes it the world's fourth-deepest lake. Cape Maclear is a prominent geographic feature in southern Lake Malawi, at the division between the two southern arms of the lake. Cape Maclear was named by David Livingstone. Aufwuchs (OWF-vookhs) is a handy German term (meaning "on-growth") for naming the complex algal community that grows on submerged rocks and other surfaces. It includes a range of both firmly attached and loose algae, cyanobacteria, and other organisms living among these algae, including diatoms, small crustaceans, worms, insect larvae, rotifers, bacteria, and others. See? It's much simpler to call it all Aufwuchs. A true eel (Anguilla bengalensis labiata) is among the fishes occurring in Lake Malawi. Every individual is born in the Indian Ocean. Those found in the lake have swum from the ocean into the Zambezi River, negotiated its falls and rapids, swum the length of the Shiré River, passed through Lake Malombe and the upper Shiré, and finally entered Lake Malawi. As improbable as it seems, the first British naval victory of World War I was won on L. Nyasa (L. Malawi). On 13 August 1914, H.M.S. Gwendolen, commanded by E.L. Rhoades, shelled and captured the German ship Hermann von Wissmann, beached for repairs at Sphinxhaven (now Liuli, Tanzania). German commander Berndt, Rhoades's close friend, was unaware that war had been declared and thought Rhoades was drunk! A catfish common on rocky shores of Lake Malawi, Synodontis njassae, has turned out to be also a very common member of the pelagic (open-water) fish community. It occurs all the way down to the lower limit of dissolved oxygen (~230 meters), feeding on zooplankton. Every night, these catfishes migrate up to the surface layers where their feeding on zooplankton increases; then they return to deeper water. The fish eagle (Haliaeetus vocifer) is common along the shores of Lake Malawi, where it is often seen snatching fish from the water as it flies. The fish eagle closely resembles the American bald eagle, which also belongs to the genus Haliaeetus. Lake Malawi's fauna contains more species of fresh-water fish than all of Europe and North America combined. Aquarists adore L. Tanganyika's "shell dwellers," small lamprologine cichlids that defend individual empty snail shells as breeding territories. But did you know that L. Malawi also has shell-dwelling cichlids? Two mbuna, Maylandia livingstonii and M. elegans, when young, hide from predators in empty Lanistes snail shells, common on sandy shores. Both species outgrow the shells, and mature and breed elsewhere. An inquiline (IN-kwil-line) is an animal that lives in the home of another and shares its food. Lake Malawi's fish fauna has an excellent example of an inquiline. Young individuals of the cichlid Maylandia livingstonii often hide in the empty shells of dead Lanistes snails on sandy shores. A tiny amphiliid catfish, Zaireichthys lacustris, lives as an inquiline in some of these cichlid-occupied shells.