@article {614,
	title = {Derived karyotypes in two elephantfish genera (Hyperopisus and Pollimyrus): lowest chromosome number in the family Mormyridae (Osteoglossiformes)},
	volume = {15},
	year = {2021},
	month = {Oct-08-2021},
	pages = {345-354},
	abstract = {<p><jats p="">The African weakly electric elephantfish family Mormyridae comprises 22 genera and almost 230 species. Up-to-date cytogenetic information was available for 17 species representing 14 genera. Here we report chromosome number and morphology in <jats italic="">Hyperopisus bebe</jats> (Lacep\&egrave;de, 1803) and <jats italic="">Pollimyrus isidori</jats> (Valenciennes, 1847) collected from the White Nile system in southwestern Ethiopia. Both taxa displayed the diploid chromosome number 2n = 40, but they differed in fundamental numbers: FN = 66 in <jats italic="">H. bebe</jats> and FN = 72 in <jats italic="">P. isidori</jats>; previously the same diploid chromosome number 2n = 40 was reported in an undescribed species of <jats italic="">Pollimyrus</jats> Taverne, 1971 (FN = 42) from the same region. Our results demonstrate that not only pericentric inversions, but fusions also played a substantial role in the evolution of the mormyrid karyotype structure. If the hypothesis that the karyotype structure with 2n = 50\&ndash;52 and prevalence of the uni-armed chromosomes close to the ancestral condition for the family Mormyridae is correct, the most derived karyotype structures are found in the <jats italic="">Mormyrus</jats> Linnaeus, 1758 species with 2n = 50 and the highest number of bi-armed elements in their compliments compared to all other mormyrids and in <jats italic="">Pollimyrus isidori</jats> with the highest number of bi-armed elements among the mormyrids with 2n = 40.</jats></p>
},
	issn = {1993-078X, 1993-0771},
	doi = {10.3897/compcytogen.v15.i4.67681},
	url = {http://dx.doi.org/10.3897/compcytogen.v15.i4.67681},
	author = {Simanovsky, Sergey and Medvedev, Dmitry and Tefera, Fekadu and Alexander Golubtsov}
}
@article {613,
	title = {First cytogenetic information for five Nilotic elephantfishes and a problem of ancestral karyotype of the family Mormyridae (Osteoglossiformes)},
	volume = {14},
	year = {2020},
	month = {Aug-19-2020},
	pages = {387-397},
	abstract = {<p><jats p="">The elephantfish family Mormyridae is the most diverse lineage of the primitive teleostean clade Osteoglossomorpha distributed in inland waters of all continents except Antarctica and Europe. The family Mormyridae is endemic to Africa and includes 22 genera and almost 230 species. The evolutionary radiation of mormyrids most probably should be attributed to their capability of both generating and receiving weak electric signals. Up-to-date cytogenetic studies have revealed substantial karyotype differentiation among the nine investigated elephantfish species and genera (a single species studied per each genus). In the present study, karyotypes of five species representing five mormyrid genera (four unexplored ones) collected from the White Nile system in southwestern Ethiopia are described for the first time. The results show substantial variety of the diploid chromosome and fundamental numbers: 2n = 48 and FN = 54 in <jats italic="">Brevimyrus niger</jats> (G\&uuml;nther, 1866), 2n = 50 and FN = 72 in <jats italic="">Cyphomyrus petherici</jats> (Boulenger, 1898), 2n = 50 and FN = 78 in <jats italic="">Hippopotamyrus pictus</jats> (Marcusen, 1864), 2n = 50 and FN = 76 in <jats italic="">Marcusenius cyprinoides</jats> (Linnaeus, 1758), 2n = 52 and FN = 52 in <jats italic="">Mormyrops anguilloides</jats> (Linnaeus, 1758). Karyotype structure in the latter species seems to be close to the ancestral condition for the family. This hypothesis is discussed in the light of available data on karyotype diversity and phylogeny of mormyrids.</jats></p>
},
	issn = {1993-078X, 1993-0771},
	doi = {10.3897/compcytogen.14i3.52727},
	url = {http://dx.doi.org/10.3897/compcytogen.14i3.52727},
	author = {Simanovsky, Sergey and Medvedev, Dmitry and Tefera, Fekadu and Alexander Golubtsov}
}
