The genus name Yssichromis is Greek based in “yssos” meaning javelin or arrow correlating to the elongated slender body shape exhibited by these cichlids. These are usually smaller fish with pointed (arrow shaped) heads with a low straight or slightly convex cranial slope. The outer rows of both jaws are made up of unequally bicuspid teeth foremost, and tricuspid towards the rear. Small tricuspid teeth make up the inner rows. The lower jaw extends beyond the upper similar to Prognathochromis (Tridontochromis) species. The premaxillary is not as obvious as the fore mentioned species. The eyes of Yssichromis species are comparatively larger than most other Haplochromines.
Most Yssichromis are considered zooplanktivores. Until the late 70’s this representatives from the genus were abundant in many portions of Lake Victoria. With the up serge of Lates niloticus in the 1980’s, Yssichromis numbers dropped off dramatically. In the early 1990’s, various Yssichromis species began to appear once again in samplings. Numbers of some species (Y. laprogramma) were more abundant in the mid 90’s than initial estimates in the 70’s (Goldschmidt 1990, Seehausen 1997). Usually thought of as an open water schooling fish (comparative to the Cyprichromis species of Lake Tanganyika) some Yssichromis found refuge from the Nile perch by blending in with large schools of cyprinid (Rastrineobola argentea).
Yssichromis sp. “blue tipped” was discovered in 1992 by Yves Fermon and Olivier Berthelot off Rusinga Island Lake Victoria. This schooling species feeds upon zooplankton and will also take small insects in the wild. Maximum size is near 10cm for males, slightly smaller for females. The body shape is slender and elongated with a straight cranial slope. The lower jaw extends slightly beyond the upper. Subdominant males have a dull red-purple back with a lighter tan colored line directly under the dorsal fin. The flanks are light lime-green with dotted with dark blotching along the mid body. The blotches run along, and are part of very faint vertical barring. The abdomen is light brown. Two dark blotches on the caudal region are joined by a thin black bar running between them. The caudal fin is translucent. The dorsal has a light blue coloration. This is where the descriptive name was derived. The anal fin is also clear with two well defined egg spots dotting the upper rear portion. Females are mostly silver in color. They have the same black blotching mid laterally that is found in males. These blotches run into each other forming an almost continuous solid line. The pelvic, anal and caudal fins have a yellow tinge to them. Some blue can be seen on the forward portion of the dorsal. Dominant males sport jet-black body coloration. This black is so intense that when reflected by light, a green sheen appears. The dorsal fin is metallic-blue frontally and the remaining portion black. There is a yellow edging to this fin. The caudal fin is black with yellow edging. The yellow coloration is thicker at both points on the fin than between them. The anal fin is black at the base with lighter colored rays. The outer portions are yellow. The (usually) two orange ocelli are surrounded by a solid black orbit. The pelvic fins are black with the first ray elongated.
Being an open water species, we house our group in a 65 gallon deep tank with a silica sand substrate. One side of this tank contains a small rock work structure. A few strands of artificial Vallisneria are situated in the middle of the tank. Filtration is provided by an Aquaclear® 300 hang on the back power filter. Weekly water changes of twenty gallons help maintain acceptable conditions. The Yssichromis sp. “blue tipped” are housed with a colony of Platytaeniodus sp. “blue neon” of similar size. This mixture works well as both species are distinct enough that hybridization is unlikely. The rock structure is used by the Platytaeniodus sp. “blue neon” as a territorial boundary but has little attraction to the Yssichromis sp.“blue tipped”. Neither species is overly aggressive with the other; squabbles are restricted to co specs. The Platyaeniodus sp. “blue neon” prefer to remain near the bottom while the Yssichromis sp. “blue tipped” are usually roaming the upper portion of the aquaria. There are occasional bluffing duels between the most dominant males of each species but these are no more than jetting forward in an attempt to back the other up. There is no physical contact or jaw locking that occurs.
As male coloration darkens, one can be certain that spawning activity is already in the works. In our colony, two males suddenly turned jet-black with intense yellow edging to the fins. The next two days were spent bluffing one another with jetting runs at one another. Both males were of equal size and neither gave in. Each maintained dominant coloration and began courting an obviously ripe female. As of yet I have been unable to witness an actual spawning but have observed the pre-spawning dance on multiple occasions. The spawning advances occur in mid strata. The female roamed from one side of the tank to the other enticing each male to shake wildly presumably provoking her into mating. After two days, one of the males had obviously succeeded in winning the female over as she had a definite extended buccal cavity. The female is not harassed at all while incubating her young. We waited for 14 days and stripped her. She had 12 nearly free swimming fry. The young were placed in an egg tumbler for two days while the remaining egg sac was absorbed. The free swimming young are now in a 20 gallon tank where they are growing rapidly on a diet of Cyclop-eeze® and crushed basic flake. The fry are hardy and present no problems with regards to rearing. Filtration in the fry tank is provided by a sponge filter. Ideally, a five gallon water change should be done twice a week.
I suspect that spawning occurs on the tank bottom. The first two occasions I had a female hold she was found to only be carrying small stones when stripped. It is probable that she had picked up these stones with her own eggs and through the process of tumbling them around her throat, they disintegrated over time. Once we changed the substrate to silica sand, this problem disappeared.
Yssichromis sp. “blue tipped” (“tipped blue” as named by Fermon and Berthelot) is a very rare fish in the North American hobby. It is not held in the LVSSP program so it is up to the hobbyist to ensure its survival. Wild populations figures are unknown but like the others members of the genus, it should be considered at risk.
- Greenwood, Peter Humphry. 1980. "Towards a phyletic classification of the 'genus' Haplochromis (Pisces, Cichlidae) and related taxa. Part II; the species from lakes Victoria, Nabugabo, Edward, George and Kivu". Bulletin of the British Museum (Natural History) Zoology Series. v. 39(n. 1), pp. 1-101 (crc00319) (摘要)
- Greenwood, Peter Humphry. 1973. "A revision of the Haplochromis and related species (Pisces: Cichlidae) from Lake George, Uganda". Bulletin of the British Museum (Natural History) Zoology Series. Series 25 (5); pp 141-242 (crc00219)
- Greenwood, Peter Humphry & J. M. Gee. 1969. "A revision of the Lake Victoria Haplochromis species (Pisces, Cichlidae), part VII". Bulletin of the British Museum (Natural History) Zoology Series. v. 18; n. 1; pp. 1-65 (crc01014)
- Katunzi, E. F. & B. J. Zoutendijk, T. Goldschmidt, J. H. Wanink & F. Witte. 2003. "Lost zooplanktivorous cichlid from Lake Victoria reappears with a new trade". Ecology of Freshwater Fish. V.12(4); pp. 237-240. DOI: 10.1046/j.1600-0633.2003.00023 (crc01280) (摘要)
- Witte, Frans & B.S. Msuku, J.H. Wanick, O. Seehausen, E.F.B. Katunzi, P.C. Goudswaard, & T. Goldschmidt. 2000. "Recovery of Cichlid Species in Lake Victoria: An Examination of Factors Leading to Differential Extinction". Reviews in Fish Biology and Fisheries. v.10(2); pp. 233-241. DOI: 10.1023/A:1016677515930 (crc01279)
© Copyright 2006 Greg Steeves, all rights reserved
Steeves, Greg. (6月 26, 2006). "Yssichromis sp. "blue tipped"". Cichlid Room Companion. 检索 4月 17, 2021, 从: https://cichlidae.com/section.php?id=139&lang=cn.