Here's the scientific publication, but I will add a summary for those not bothered enough to read it
https://royalsocietypublishing.org/doi/10.1098/rsos.220201
This group of fish will be best known to hobbyists for the stunning Empire gudgeon (???????????? ?????????), a popular if not so common species in the hobby.
The assemblage of species of this genus (????????????) which occurs in the basin of the Murray-Darling river system is made up of sexually reproducing species and hybrid lineages which consist of a single-sex and which have arisen through hybridisation, a process known as hybridogenesis. The single-sex species require gametes from the sexual species to reproduce and could be regarded as sexual parasites and in "closed populations" this sexual parasitism can cause the extinction of such populations. Reproduction is, therefore 'hemiclonal'.
A hemiclonal hybrid is produced by a mating between two parental species (genotypes GG and SS) and, although this individual has received half its genome from each parental species (genotype GS), it only passes on genetic material from one of them to its offspring (egg with genotype G).
https://www.sciencedirect.com/.../abs/pii/S0169534711000814
Read more about ???????????? in our post from March earlier this year - https://www.facebook.com/FishInTheNews/posts/pfbid033ZqbT8bFSdGiJQ9gqec788qhWAJ87o2HfFCw5sJ3swVDHyGw1VeH7bQjGxVPYkNXl
???????? ?????
Species delineation and systematics of a hemiclonal hybrid complex in Australian freshwaters (Gobiiformes: Gobioidei: Eleotridae: ????????????)
????????
Thacker CE, Geiger DL, Unmack PJ. 2022. Species delineation and systematics of a hemiclonal hybrid complex in Australianfreshwaters (Gobiiformes: Gobioidei: Eleotridae: ????????????). R. Soc. Open Sci.9: 220201. DOI: https://doi.org/10.1098/rsos.220201
????????
The rivers of southeastern Australia host a species complex within the carp gudgeon genus ???????????? that includes parental species and hemiclonal hybrid lineages. These hemiclones can be difficult to distinguish from their parent taxa, making delineation of species unusually difficult. We approach this historical taxonomic problem by using single nucleotide polymorphism (SNP) genotyping to distinguish individuals of each species and hemiclones, enabling us to quantify the variation among evolutionary lineages and assign names to the species. ???????????? ??????????? remains valid and does not have any hemiclones.
We describe ???????????? ?????ℎ??? and ???????????? ????????ℎ??? from the Murray-Darling Basin and ???????????? ????????? from the Murray-Darling as well as eastern coastal streams north of the Mary River, part of the range attributed to ?. ?????.
We further split ?. ????? to distinguish a species from the Mary River, ???????????? ????????????????. We designate a neotype and redescribe ?. ????? due to uncertainty about the source and species identity of specimens used in the original description. We reconcile previous taxonomies, provide new common names for parental species, and advocate using the scientific names of both parents when referring to the hemiclone hybrids to avoid confusion with previous common names that did not distinguish parental taxa and hemiclones.
https://royalsocietypublishing.org/doi/10.1098/rsos.220201
This group of fish will be best known to hobbyists for the stunning Empire gudgeon (???????????? ?????????), a popular if not so common species in the hobby.
The assemblage of species of this genus (????????????) which occurs in the basin of the Murray-Darling river system is made up of sexually reproducing species and hybrid lineages which consist of a single-sex and which have arisen through hybridisation, a process known as hybridogenesis. The single-sex species require gametes from the sexual species to reproduce and could be regarded as sexual parasites and in "closed populations" this sexual parasitism can cause the extinction of such populations. Reproduction is, therefore 'hemiclonal'.
A hemiclonal hybrid is produced by a mating between two parental species (genotypes GG and SS) and, although this individual has received half its genome from each parental species (genotype GS), it only passes on genetic material from one of them to its offspring (egg with genotype G).
https://www.sciencedirect.com/.../abs/pii/S0169534711000814
Read more about ???????????? in our post from March earlier this year - https://www.facebook.com/FishInTheNews/posts/pfbid033ZqbT8bFSdGiJQ9gqec788qhWAJ87o2HfFCw5sJ3swVDHyGw1VeH7bQjGxVPYkNXl
???????? ?????
Species delineation and systematics of a hemiclonal hybrid complex in Australian freshwaters (Gobiiformes: Gobioidei: Eleotridae: ????????????)
????????
Thacker CE, Geiger DL, Unmack PJ. 2022. Species delineation and systematics of a hemiclonal hybrid complex in Australianfreshwaters (Gobiiformes: Gobioidei: Eleotridae: ????????????). R. Soc. Open Sci.9: 220201. DOI: https://doi.org/10.1098/rsos.220201
????????
The rivers of southeastern Australia host a species complex within the carp gudgeon genus ???????????? that includes parental species and hemiclonal hybrid lineages. These hemiclones can be difficult to distinguish from their parent taxa, making delineation of species unusually difficult. We approach this historical taxonomic problem by using single nucleotide polymorphism (SNP) genotyping to distinguish individuals of each species and hemiclones, enabling us to quantify the variation among evolutionary lineages and assign names to the species. ???????????? ??????????? remains valid and does not have any hemiclones.
We describe ???????????? ?????ℎ??? and ???????????? ????????ℎ??? from the Murray-Darling Basin and ???????????? ????????? from the Murray-Darling as well as eastern coastal streams north of the Mary River, part of the range attributed to ?. ?????.
We further split ?. ????? to distinguish a species from the Mary River, ???????????? ????????????????. We designate a neotype and redescribe ?. ????? due to uncertainty about the source and species identity of specimens used in the original description. We reconcile previous taxonomies, provide new common names for parental species, and advocate using the scientific names of both parents when referring to the hemiclone hybrids to avoid confusion with previous common names that did not distinguish parental taxa and hemiclones.
