News on cichlids
By Thomas Andersen (18-Feb-2012)
A new paper by Sven Kullander published in the recent issue of Zootaxa formally describe Krobia xinguensis from localities in the headwaters and in the lower part of the rio Xingu. It is distinguished primarily by a deeper caudal peduncle, and details of its color pattern, including contrasting interorbital stripes and a small dark spot anteriorly on each side of the lower jaw, and a rich orange coloration in live specimens. Krobia xinguensis has previously been known as Krobia sp. "xingu" in the aquarium hobby. In the paper Kullander also state that K. potaroensis and K. paloemeuensis, currently assigned to Krobia, is better included in the catch-all genus Aequidens, until further morphological analyses may provide support for an alternative generic classification of these two species.
By Juan Miguel Artigas Azas (27-Jan-2012)
A recently published study by Sven O. Kullander and Tyson R. Roberts (2011) shows that some Lake Tanganyika endemic fishes, including at least seven cichlids (one potentially undescribed) inhabit also the rapids of the Lukuga River (a river draining the lake) as far as 100 km away from it. This shows that the belief that Lake Tanganyikan cichlids can just survive in the particular lacustrine conditions where they evolved may be have to be reconsidered. Cichlid species found were Astatotilapia burtoni, Ctenochromis horei, Simochromis babaulti, Simochromis diagramma, Telmatochromis dhonti, Tylochromis polylepis, and a potentially undescribed Tanganicodus species, in an stable fish community independent of the lake.
By Juan Miguel Artigas Azas (21-Jan-2012)
A new paper by Topi K. Lehtonen, Jeffrey K. McCrary and Axel Meyer has been published in the online magazine Plos One on January 9, 2012. The paper deals with the response of parental Amphilophus zaliosus in Lake Apoyo Nicaragua, to the approaches of the introduced predator Gobiomorus dormitor, the sleeper goby. The study shows that A. zaliosus, not familiar with the predator, allows it to come closer to its fry before starting a defense behavior, which may cause a higher predation rate on the fry. Gobiomorus dormitor, present natively in other lakes where related Amphilophus species inhabit, is attacked at a farther distance in every occasion. The study shows one of the dangers that introduced species pose to native fauna.
Lehtonen, Topi K & J.K. McCrary, A. Meyer. 2012. "Introduced Predator Elicits Deficient Brood Defence Behaviour in a Crater Lake Fish". Plos One. 7(1):e30064. DOI: 10.1371/journal.pone.0030064 (crc04136) (abstract)
By Thomas Andersen (06-Jan-2012)
An interesting paper on the genus Crenicichla has been published in the latest issue of Molecular Phylogenetics and Evolution. A molecular analysis combining both mitochondrial and nuclear genes demonstrates that Crenicichla consist of two major clades, the first including the C. wallacii, C. lugubris, and C. saxatilis species-groups, as well as Teleocichla, and the second of the C. reticulata and C. lacustris species-groups, and C. macrophthalma. The study furthermore confirm the monophyly of the C. lacustris species-group with a very high support. A biogeographic reconstruction of this species-group using dispersal-vicariance analysis underlines the importance of ancient geographic barriers between the middle and upper Paraná River (the Guaíra Falls) and between the middle and upper Uruguay River (the Moconá Falls). The phylogeny presented in the paper also recovers two endemic species flocks within the C. lacustris group, the well known Crenicichla missioneira species flock from the Uruguay River, and the newly discovered Crenicichla mandelburgeri species flock from the Paraná/Iguazú Rivers. Among the many other interesting aspects of the paper is the finding, that within the nominal species C. lacustris three deeply isolated allopatric lineages are recovered. Two of these lineages agree with the nominal taxa C. biocellata and C. dorsocellata today considered synonyms of C. lacustris The generic distances between them indicate several million years of isolation and support the existence of several species.
Piálek, Lubomír & O. Rícan, J. Casciotta, A. Almirón, J. Zrzavy. 2012. "Multilocus phylogeny of Crenicichla (Teleostei: Cichlidae) with biogeography of the C. lacustris group: Species flocks as a model for sympatric speciation in rivers". Molecular Phylogenetics and Evolution. 62(1):46-61 (crc04105) (abstract)
By Thomas Andersen (05-Jan-2012)
A new paper published in Journal of Evolutionary Biology demonstrates that the course of speciation in the genus Steatocranus repeatedly has been affected by hybridization events. The genus radiated under riverine conditions in the lower Congo rapids and produced a small species flock. An analysis explicitly testing for patterns of ancient gene flow provides evidence for a highly reticulate phylogenetic history of the genus.
Schwarzer, Julia & B. Misof, U.K. Schliewen. 2012. "Speciation within genomic networks: a case study based on Steatocranus cichlids of the lower Congo rapids". Journal of Evolutionary Biology. 25(1):138-148 (crc04104) (abstract)
By Juan Miguel Artigas Azas (04-Jan-2012)
The first published picture of Pterochromis congicus ever has appeared as the cover of Cichlid News January 2012 issue. The picture was taken by Oliver Lucanus in his aquarium and corresponds to an specimen from Lac Mai Ndombe [Democratic Republic of Congo] in the Congo River drainage. According to Oliver, the fish seems to be extremely rare in nature, often being outnumbered by Tylochromis, Hemichromis, Sarothoredon and Tilapia by 100 to 1. We were also supplied by Oliver with not one but two pictures of this amazing fish, which are now part of our cichlid catalog, as the first pictures of this fish online.
By Ad Konings (04-Jan-2012)
Martin Genner and George Turner compared the nuclear DNA with that of mitochondria in a series of Malawi cichlids and found that on the basis of nuclear DNA the deep-dwelling species (Placidochromis, Lethrinops, Alticorpus) were closely related to morphologically similar forms of the shallow water (all other non-mbuna), but if they compared the mitochondrial DNA they were surprised to find all the deep water species nested within the mbuna. Years ago, Moran & Kornfield (1993) had similar results using mitochondrial DNA probes when they claimed that e.g. Alticorpus was closer related to mbuna than to shallow water Lethrinops. This then resulted in disbelieve and the abandonment of mtDNA phylogenies (since they were not congruent with old-fashioned morphology) in favor of nuclear DNA phylogenies. Now, when Genner & Turner compared the two methods they come to a very interesting conclusion in that (pre)mbuna and the precursor(s) of the deep-water cichlids hybridized a long time ago before the deep-water species developed into what they are today. They also give an interesting discussion in which they argue that the hybridization may have given the hybrids a set of altered genes that actually allowed them to explore and adapt to different habitats (the deep, dark waters of the lake). Clearly the deep-water species of Lake Malawi need more study.
Genner, Martin & G.F. Turner. 2012. "Ancient hybridization and phenotypic novelty within Lake Malawi’s cichlid fish radiation". Molecular Biology and Evolution. 29,(1):195-206. DOI: 10.1093/molbev/msr183 (crc04055) (abstract)
By Juan Miguel Artigas Azas (20-Dec-2011)
The most likely identification for Cynotilapia afra is given by Ad Konings after digging into the historic aspects of the collection of the type material and comparing its features. Microchromis is thus kept as a junior synonym of Cynotilapia. Comments on the validity of Cynotilapia aurifrons are also offered in this article published today in The Cichlid Room Companion.
Konings, Ad. 2011. "Some critical remarks on Cynotilapia and Microchromis". The Cichlid Room Companion. Retrieved on December 20, 2011, from:http://www.cichlidae.com/article.php?id=369 (crc04098) (abstract)
By Juan Miguel Artigas Azas (15-Dec-2011)
A new paper authored by Sven Kullander, dealing with the disscussion about the correct generic assignation for Mikrogeophagus ramirezi, the Venezuelan ram, is published today in Zootaxa. This taxonomically difficult cichlid has been for decades the center of a discussion about what is the correct generic name applicable (Mikrogeophagus, Papiliochromis, Microgeophagus, Pseudogeophagus, Pseudoapistogramma). Reasons of why Mikrogeophagus Meulengracht-Madsen 1968 should be applied to this fish are given.
Kullander, Sven. 2011. "Nomenclatural availability of putative scientific generic names applied to the South American cichlid fish Apistogramma ramirezi Myers & Harry, 1948 (Teleostei: Cichlidae)". Zootaxa. (3131):35–51 (crc04094) (abstract)
By Juan Miguel Artigas Azas (14-Dec-2011)
A new paper by Patrick Tawil about Cynotilapia has been just published in Cybium. It turns out that the fish we have been widely knowing as Cynotilapia afra has been wrongly identified, its real identification being Cynotilapia zebroides, previously considered a junior synonym of C. afra. The paper also offers the scientific description for C. sp 'mbamba', which we will now know as C. aurifrons, a proper specific name for it. One debatable aspect of the paper includes the proposed resurrection of the genus Microchromis, which has been considered a junior synonym of Cynotilapia.
Tawil, Patrick. 2011. "Description of a new cichlid species from Lake Malawi, with reexamination of Cynotilapia afra (Günther, 1893) and Microchromis zebroides Johnson, 1975". Cybium. 35(3):201-211 (crc04046) (abstract)
By Juan Miguel Artigas Azas (13-Dec-2011)
A new paper by Tetsumi Takahashi, Haruki Ochi, Masanori Kohda and Michio Hori has been published in the electronic magazine Biological Letters, showing that in the Lake Tanganyika school forming cichlid Microdontochromis rotundiventralis, whose schools are comprised by both mouth-brooding and non mouth-brooding individuals, it is more likely that the biological father holds larger fry passed by the female, which shows that the pair bond is maintained by this species at least until that point in the school, without apparent physical proximity of the pair.
By Juan Miguel Artigas Azas (13-Dec-2011)
A new species of Cichlasoma, Cichlasoma zarskei by Felipe Ottoni (Federal University of Rio de Janeiro) has been published today in the electronic version of Vertebrate Zoology. The new species, closely related to Kullander's Cichlasoma orientale, was previously known as Cichlasoma cf. orientale 'Maranhão' and differs from C. orientale among other aspects; by having a longer snout, wider head and shorter lower jaw. It is restricted to the Maranhão River basin in northern Brazil.
By Juan Miguel Artigas Azas (13-Dec-2011)
A new species of Apistogramma, Apistogramma playayacu has been described and published today in the electronic version of Vertebrate Zoology. The new species inhabits in the Ecuadorian Napo River system and probably belongs to the Apistogramma macmasteri species complex. It is the 71th species of Apistogramma described.
Römer, Uwe. 2011. "Apistogramma playayacu sp. n.: Description of a new cichlid species (Teleostei: Perciformes: Geophaginae) from the Rio Napo system, Ecuador". Vertebrate Zoology. 61(3):321 – 333 (crc04092) (abstract)
By Juan Miguel Artigas Azas (25-Oct-2011)
Rolf C. Hagen was a pillar in the pet products industry who touched many with his generosity and compassion. It is with profound sadness that we announce the passing of Rolf C. Hagen, who left us suddenly yet peacefully at his home in Montreal surrounded by his loving wife Marianne and grandson Justin on Saturday, October 22, 2011 (From the Montreal Gazzete).
By Juan Miguel Artigas Azas (20-Oct-2011)
A new paper by Bernd Egger., Yuri Klaefiger., Anya Theis & Walter Salzburger has been published in the digital magazine Plos One. The paper deals with the role of egg-spots on haplochromine male cichlids anal fins as an attractor for females. Males of about 1500 mouth-brooding species utilize these conspicuous egg-dummies during courtship apparently to attract females and to maximize fertilization success. The purpose of the experiment is to test the hypothesis that the evolution of haplochromine egg-spots was triggered by a pre-existing bias for eggs or egg-like coloration. The results of the tests indeed revealed that females are attracted by egg-spots, and those colors preferred are yellow, orange or red.
Egger, Bernd & Yuri Klaefiger, Anya Theis, Walter Salzburger. 2011. "A sensory bias has triggered the evolution of egg-spots in cichlid fishes". Plos One. 6(10):e25601. DOI: 10.1371/journal.pone.0025601 (crc03899) (abstract)
By Juan Miguel Artigas Azas (15-Oct-2011)
One new behavior study by Bruintjes, Rick, D. Bonfils, D. Heg M. Taborsky on the highly researched Neolamprologus pulcher has been published in PLoS ONE. The study shows that in the colony cooperative breeding species, subordinate males (those that are not the dominant male in a colony) can gain paternity mating with individuals in the colony. Such paternity makes them more eager to defend the colony against potential egg predators than those males not participating in reproduction.
Bruintjes, Rick & D. Bonfils, D. Heg, M. Taborsky. 2011. "Paternity of subordinates raises cooperative effort in cichlids". Plos One. 6(10):e25673. DOI: 10.1371/journal.pone.0025673 (crc03886) (abstract)
By Juan Miguel Artigas Azas (10-Oct-2011)
Two new species of Stigmatochromis from southern Lake Malaŵi have been described by Jay R. Stauffer Jr, Rachel M. Cleaver-Yodera, and Ad Konings, namely Stigmatochromis macrorhynchos and Stigmatochromis melanchros, the paper appearing today in the Proceedings of the Biological Society of Washington.
Stauffer, Jay Richard Jr. & R.M. Cleaver-Yoder, A. Konings. 2011. "Two new species of Stigmatochromis (Teleostei: Cichlidae) from Lake Malawi, Africa". Proceedings of the Biological Society of Washington. 124(3):212-222. DOI: 10.2988/10-30.1 (crc03872) (abstract)