This interesting piscivorous cichlid was first discovered, and collected, in December 2012, when Old World Exotic Fish, Inc, owned by Laif Demason, sent one of his collecting teams to the area of Lake Victoria around the northern region of the Mwanza Gulf to collect cichlids. His team of divers gathered various species at three locations, Makobe Island, Juma Island, and in the northern Mwanza Gulf itself, exact location unknown. Most locations collected at were primarily rocky biotopes. However, this species was collected offshore from Juma Island, in the area a few meters away from where the rocks end and the sandy/muddy bottom begins, water depth likely less than 8 meters depth, and so were collected over a muddy/sandy bottom and not within the rocky shoreline of this island. Juma Island is located about 6 miles just northwest of the entrance to the Mwanza Gulf.
It is significant that such a piscivore was collected (albeit only 4 were collected) since this island and the Mwanza Gulf had been regularly sampled for many years by the team in Leiden University, and yet this species had not previously been encountered. One possible explanation may have to do with this species being usually found outside this area of the lake, and that over time, had slowly migrated into this region.
This undescribed species, thought to belong to the genus Harpagochromis, reaches a maximum size of 18 cm. Their sub-adult coloration, at least up to the size of approximately 7.5 cm, shows yellow unpaired fins, and melanic cross hatch pattern of horizontal and vertical bars. These two elements seem to become more muddied/obscured as they reach adulthood, and in the male sex, develop a subtle reddish cast to the unpaired fins. This species is most likely undescribed, as all other piscivorous species from this portion of the lake do not possess the cross hatch patterning in juveniles and sub-adults along with yellow unpaired fins that give way to subtle reddish cast on adult males. Also, every other piscivore in this area, such as H. kujunjui, H. dichrorous, H. chrysogynaion, and H. pyrropteryx possess stouter bodies and deeper heads than does this undescribed species. Coloration, too is completely different with this new species over and against the other four aforementioned piscivores. Lastly, this new species has a somewhat more thickened body, when viewed cross-sectionally, and not so laterally compressed as in the other formally described piscivorous species. I propose to provisionally call it Harpagochromis sp. 'serranus juma island' until more studies are carried out to determine if should be considered a new taxon or not.
© Copyright 2015 Mark Smith, all rights reserved
Smith, Mark. (January 30, 2015). "Harpagochromis sp. 'serranus juma island'". Cichlid Room Companion. Retrieved on December 16, 2018, from: https://www.cichlidae.com/article.php?id=441.