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by Anton Lamboj |
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The cichlid genus Pelvicachromis, whose members are found in West and Central Africa, is possibly one of the most beloved and desired genera for dwarf cichlid lovers—at least for those who are focused on Africa. With all the numerous color morphs known, Pelvicachromis taeniatus (Boulenger, 1901) is surely a favorite within this genus. The taxonomic history of the species is, on the one hand, interesting, but on the other also a bit confusing.
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The species had been originally described as a member of the genus Pelmatochromis, in which it remained for decades. In 1968, the Belgian ichthyologist Thys van den Audenaerde published a revision of the genus Pelmatochromis in which he created a number of subgenera, but also synonymized some taxa. One of the new subgenera erected, Pelvicachromis, was subsequently established as a genus by Trewavas (1974). In his revision, Thys van den Audenaerde synonymized Pelvicachromis (Pelmatochromis) kribensis (Boulenger, 1911) and P. kribensis calliptera (Pellegrin, 1929), both described from southern Cameroon, with P. taeniatus, which has its type locality in Nigeria. Unfortunately, Thys van den Audenaerde did not state clear reasons for the synonymy; he referred only to certain color patterns of the male caudal fin (such as the number of ocelli) and to the poor coloration in the types of P. taeniatus. No morphological details or other arguments for the synonymy were given. Later, in 1987, Greenwood published a more detailed analysis on the phylogeny and anatomy of pelmatochromine cichlids. He established the tribe Chromidotilapiini for all genera that lack microbranchiospines (includes Pelvicachromis) and erected two new genera within the group, Limbochromis and Parananochromis. Greenwood’s publication contained no discussions on the species level and hence Thys van den Audenaerde’s P. taeniatus remained largely untouched. Subsequently, in all scientific publications after Thys van den Audenaerde (1968), P. kribensis had been treated as a junior synonym of P. taeniatus. This was likely based on the fact that anatomical or morphological differences between populations of the species were not or only very poorly recognizable—which is a well-known condition for several species groups within the genus (see e.g. Lamboj & Stiassny, 2007). In contrast to the scientifically accepted classification, several authors of aquaristic articles questioned the validity of Thys van den Audenaerde’s synonymy, with their main arguments based on differences in coloration between live specimens from Nigeria and Cameroon (e.g. Paulo, 1977; Loiselle & Castro, 1980). Some of these publications presented a few morphological data, but none of these were based on type material or specimens deposited in collections. Also, neither of the articles were published in scientific journals, nor did the authors state unambiguous conclusions, so consequently none of these had been recognized or accepted as valid revisions. | |
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Over the years (starting at about 1970) numerous geographical color morphs of P. taeniatus had been discovered by the ornamental fish trade and by aquarists collecting cichlids in Cameroon. It became evident that at least three main groups could be distinguished within the species and that also some color variation exists within most of these groups (Lamboj, 2004). These three groups are: 1. A group from the Niger River system in Nigeria and Benin with distinct coloration differences when compared to the other two groups. 2. A Cameroon group represented by two similar clusters of populations from regions around Mount Cameroon and from localities south of the Nyong River. 3. A second Cameroon group consisting of only one form known from the Wouri River system. Most differences both within and between the three groups are found in the male-specific coloration, less so in the female color pattern. A molecular investigation of several specimens, combined with morphological and anatomical data formed the basis of a recent revision of the P. taeniatus group (Lamboj et al., 2014), the results of which I want to explain here in hopefully an understandable way. Since the main differences between species are found in the color pattern of the dorsal and caudal fins, I will focus on these. An important result of the revision was that the name P. taeniatus has been restricted to specimens from Nigeria and Benin only (as it was in the original description). This includes all the forms we know from the Niger River system, e.g. the forms called “Yellow”, “Green”, “Warri”, “Calabar”, “Red Cheek”, and “Nigeria Red” (which appears to be a line-bred form). Main coloration differences to the other species/forms from Cameroon are as follows: In males, the upper half of the caudal fin is whitish to yellow, with 3–12 dark dots (the number varies between individuals), and the lower half has a black margin and a white to yellow submargin, while the central field of the fin is reddish with 4–8 rows of blue spots. In females, the dorsal fin is iridescent yellow, with a black margin and a whitish to bluish submarginal band. The black margin is widest on the first 1–2 spines and continues from the tip of the spine down to the base of dorsal fin. Posterior of these two spines the black margin tapers toward the end of the fin and is absent on the last two or three rays. One or two black dots are visible in the soft-rayed part in some individuals. The caudal fin is yellow with a dark gray to black margin and 1–3 horizontal dark bars stretching over the length of the fin, of which the central bar is the most prominent extending from the dark midlateral band. The upper half of the caudal sometimes show 1–3 black dots in some individuals (rarely more, in which case it could be the result of captive breeding, as I have not yet seen it in wild-caught specimens). | |
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The second form from Cameroon, previously known as P. taeniatus “Wouri” is now described as P. drachenfelsi. Its distribution is restricted to the Wouri River system; currently we know of just two localities. Both are small tributaries of the main river containing black water of low conductivity and pH. The main color characteristics of the male’s caudal fin are that its upper half has a white margin, which is bordered by a dark submarginal band and by a second submarginal band which is white to bluish. The black submarginal band becomes the margin in the lower half which lacks the white margin, and the second white to bluish submargin of the upper half continues to a white to pale bluish submargin in the lower half. The pattern is very characteristic and not found in the other two species discussed in this article. The central field of the caudal is reddish and with four to seven rows of blue spots, which are more prominent in the lower parts of the fin. Females have an iridescent yellow dorsal fin with a thin black margin, with in some specimens an additional narrow, bluish submarginal band. The first two spines of the dorsal and the membranes between these spines are black. One or two black dots may be present in the soft-rayed part. The caudal fin is yellow with a dark gray to transparent margin. The upper half often has an iridescent bluish to pale violet hue, with one or two black dots in some individuals. | |
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All remaining forms from Cameroon are now referred to by the old species name, P. kribensis (Boulenger, 1911). This surely will cause some confusion for a while, as the common name “Krib” usually is connected with the species P. pulcher. I just hope that hobbyists will start to use the scientific names now more often to avoid confusion. However, the well-known forms of P. kribensis, such as “Kienke”, “Nange”, “Lobe”, “Nyete” (or “Niete”), “Bipindi”, “Bandwouri” 1 and 2, (or “Bandevouri”), “Loukoundje”, “Dehane”, “Moliwe”, and “Ndonga” are now all forms of P. kribensis. Of course “Muyuka”, “Kumba”, and “Njanje” are too, but these three “forms” have a peculiar aspect in common; they all originate from specimens collected in other areas and which have been introduced in creeks around the town of Kumba. Unfortunately, we neither know where they were collected nor whether the current forms are a mix or pure specimens. We now know for certain that these forms were introduced in the area, which was confirmed by African collectors as well as by the person who organized the introductions about 40 years ago. Main coloration characteristics of P. kribensis are as follows: The upper half of the male caudal fin has most often a red margin that is bordered by a white to bluish submarginal band in populations from the Lobe River system. The lower margin of the fin is usually dusky black to greenish. In most populations a white to yellow field in the upper half contains 2–8 black dots, but these are absent in all populations from the Lobe River system (forms “Lobe” and “Nyete”) and in some specimens of the form known as “Bandwouri 2”. Collectors informed me that they collect fish without dots—“Bandewouri 1”—at different places, but I would not exclude that “Bandewouri 2“ is from the Lobe system and just given a different name to increase sales. In addition, the villages of Bandewouri and Bipindi, which are supposed to have “different” forms, are less then 10 km (6 mi) apart on the same road. The central field of the caudal fin in P. kribensis is reddish with four to seven rows of blue spots, which are more prominent in the lower half. The females of P. kribensis have a dorsal fin with an iridescent whitish to yellow coloration and a thin black margin that is bordered by a narrow, bluish submarginal band in some specimens. The black margin is widest on the first spines and narrows toward the posterior part of the fin, and is usually absent on the last four to six rays. Some individuals have 1–3 black dots in the soft rayed part. The caudal fin is yellow, with a dark but indistinct margin. The upper half sometimes contains one to a few black dots. I can not exclude that P. kribensis as currently diagnosed may in fact contain more than one species, because the forms “Moliwe” and “Ndonga” as well as “Dehane” are geographically separated from the other forms all occurring south of the Nyong River. In order to resolve this situation many more individuals from all forms and from additional localities, especially from north of the Nyong River which were not available for the revision, should be examined and their genetic markers analyzed. Additionally, it would certainly be interesting to analyze the genetics of the introduced forms from the area between Kumba and Muyuka to clear up their origin (even though it may be more of interest to aquarists than for science). However, I hope that the aquarists will quickly become familiar with and use the names that were proposed in my revision. Without doubt these name changes will have no influence on the fact that all these cichlid species are beautiful and very interesting dwarf cichlids. Greenwood P.H., 1987. The genera of pelmatochromine fishes (Teleostei, Cichlidae). A phylogenetic review. Bull. Br. Mus. (Nat. Hist.), Zool. Ser., 53: 139-203. Lamboj A., 2004. The Cichlid Fishes of Western Africa. 255 p. Bornheim: Birgit Schmettkamp Verlag. Lamboj A. & M.L.J. Stiassny, 2007. Pelvicachromis Thys van der Audenaerde 1968: 313–319 In: Stiassny, Teugels & Hopkins (eds.) Poissons d’eaux douces et saumâtres de basse Guinée Afrique centrale de l’Ouest. Lamboj, A., D. Bartel, & E. Dell’Ampio, 2014. Revision of the Pelvicachromis taeniatus-group (Perciformes), with revalidation of the taxon Pelvicachromis kribensis (Boulenger, 1911) and description of a new species. Cybium, 38 (3): 205–222. Loiselle P.V. & A.D. Castro, 1980. The status of Pelvicachromis kribensis (Boulenger, 1911) (Pisces, Cichlidae). Buntbarsche Bulletin, 81: 13–21. Paulo, J., 1977. Anmerkungen zur Gattung Pelvicachromis, speziell zur Berechtigung des Taxons Pelvicachromis kribensis (Boulenger, 1911). DCG-Inf., 8(9): 161-168. Thys van den Audenaerde D.F.E., 1968. A preliminary contribution to a systematic revision of the Genus Pelmatochromis Hubrecht senu lato (Pisces, Cichlidae). Rev. Zool. Bot. Afr., 77: 349–391. Trewavas E., 1974. The freshwater fishes of rivers Mungo and Meme and lakes Kotto, Mbodaong, and Soden, West Cameroon. Bull. Br. Mus. (Nat. Hist.), Zool. Ser., 26: 328–419. |
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