Cryptic mitochondrial (mt) lineages are known to exist in the earthworm morphospecies Lumbricus r... more Cryptic mitochondrial (mt) lineages are known to exist in the earthworm morphospecies Lumbricus rubellus and L. terrestris. The latter was recently split into two species, L. terrestris and L. herculeus, based on large genetic distances and a statistical difference in body size. There is support for the separation of some lineages in L. rubellus into species, whereas other lineages, separated by similar mt genetic distances, have been found to be part of the same species. However, no study has evaluated the status of the cryptic mt lineages in L. terrestris-L. herculeus and L. rubellus using nuclear genes. We use a combination of methods to reveal extensive cryptic speciation and limited hybridization in Lumbricus, based on one nuclear (H3) and one mitochondrial (COI) marker. Using a Bayesian multi-locus species delimitation method, as well as single gene haplotype networks and gene trees, we delimit seven well supported cryptic species within the morphospecies L. rubellus, and confirm the split within the species-pair L. terrestris-L. herculeus. Limited hybridization was found between the most common species of L. rubellus (A) in northern Europe and two other species (B and H) in this complex, as well as between L. terrestris and L. herculeus. Deep mt divergence was found within L. terrestris s.str. but no support for further splitting of this taxon was found. Both L. rubellus and L. terrestris are well studied model organisms, and considering that cryptic species and hybridization were found within them, it is important that they are properly identified in future studies.
An aberrantly coloured male Golden Whistler Pachycephala pectoralis, lacking yellow pigment, is r... more An aberrantly coloured male Golden Whistler Pachycephala pectoralis, lacking yellow pigment, is reported from the Bellarine Peninsula, Victoria. This could be the first documented case of this colour aberration in the species.
DNA-barcoding, using the mitochondrial marker COI, has been found successful for the identificati... more DNA-barcoding, using the mitochondrial marker COI, has been found successful for the identification of specimens in many animal groups, but may not be suited for species discovery and delimitation if used alone. In this study, we investigate whether two observed COI haplogroups in the earthworm Aporrectodea longa correspond to two cryptic species or if the variation is intraspecific. This is done by complementing COI with two nuclear markers, ITS2 and Histone 3. The variation is studied using distance methods, parsimony networks and Bayesian coalescent trees, and the statistical distinctness of the groups is tested on gene trees using the genealogical sorting index, Rosenberg's PAB and Rodrigo et al.'s P(RD). We also applied multilocus species delimitation based on the multispecies coalescence model. The two haplogroups were found in COI, and all tests except P(RD) found them to be significantly distinct. However, in ITS2, the same groups were not recovered in any analyses or tests. H3 was invariable in A. longa, and was, therefore, included only in the multilocus analysis, which preferred a model treating A. longa as one species over a model splitting it into two. We also compared two measurements of size, body length, and no. of segments between the groups. No difference in body length was found, and although a significant difference in no. of segments was noted the haplogroup with the lower mean showed both the highest and the lowest value. When combined, these results led us to the conclusion that there is no support for the separation of A. longa into two cryptic species. This study again highlights the importance of complementing mitochondrial barcodes with more data when establishing species boundaries.
The five Nordic species of the genus Urytalpa Edwards (Diptera: Keroplatidae) are revised, of whi... more The five Nordic species of the genus Urytalpa Edwards (Diptera: Keroplatidae) are revised, of which one species, Urytalpa galdes Hedmark & Kjaerandsen, sp.n., is described as new to science based on males collected in northern Sweden. We find that the original type species assignment for Urytalpa (Platyura ochracea Meigen, 1818) is based on a misidentification, and in order to stabilize the nomenclature we therefore select a new type species, Urytalpa dorsalis (Staeger, 1840), sp. restit. A lectotype is designated for Orfelia ochracea (Meigen, 1818), comb. n. = Orfelia unicolor (Staeger, 1840), syn. n. The males of U. atriceps (Edwards, 1913), U. dorsalis, U. macrocera (Edwards, 1913) and U. trivittata (Lundström, 1914), and the females of U. dorsalis , U. macrocera and U. trivittata are described and illustrated based on Nordic material. As the first known Nearctic representative of Urytalpa, U. nigrita (Johannsen, 1910), comb. n., known from western USA Washington) and Canada, is ...
ABSTRACT Martinsson, S., Kjærandsen, J. & Sundberg, P. (2011). Towards a molecular phylog... more ABSTRACT Martinsson, S., Kjærandsen, J. & Sundberg, P. (2011). Towards a molecular phylogeny of the fungus gnat genus Boletina (Diptera: Mycetophilidae). —Zoologica Scripta, 40, 272–281.Boletina is a species rich genus of fungus gnats (Diptera: Mycetophilidae) with a mainly Holarctic distribution. The systematics within the genus has gained little attention and this is a first attempt to shed some light over the systematics of Boletina and to test the segregation of the genera Saigusaia and Aglaomyia from Boletina. The nuclear marker 28S and mitochondrial 16S, COI and CytB were amplified and sequenced for 23 taxa that were analysed separately and together with a broad sample of outgroup taxa obtained from GenBank, where also 18S sequences were added. Phylogenies were estimated using maximum likelihood, Bayesian inference and parsimony. We strengthen the hypothesized sister-group relationship between Docosia and Boletina, but the genus Boletina as currently delimited appears to be paraphyletic and nested in a clade together with Aglaomyia, Coelosia and Gnoriste. The genus Saigusaia, on the other hand, seems to be well separated from Boletina. The Boletina erythropyga species group is consistently found as a distinct basal clade within Boletina s.l. The results obtained are otherwise ambiguous both for the taxa in focus and in some analyses globally with a statistically supported total breakdown of the traditional higher classification into tribes, subfamilies and even families. Interestingly, this breakdown almost disappeared when additional 18S sequences were added.
Cryptic mitochondrial (mt) lineages are known to exist in the earthworm morphospecies Lumbricus r... more Cryptic mitochondrial (mt) lineages are known to exist in the earthworm morphospecies Lumbricus rubellus and L. terrestris. The latter was recently split into two species, L. terrestris and L. herculeus, based on large genetic distances and a statistical difference in body size. There is support for the separation of some lineages in L. rubellus into species, whereas other lineages, separated by similar mt genetic distances, have been found to be part of the same species. However, no study has evaluated the status of the cryptic mt lineages in L. terrestris-L. herculeus and L. rubellus using nuclear genes. We use a combination of methods to reveal extensive cryptic speciation and limited hybridization in Lumbricus, based on one nuclear (H3) and one mitochondrial (COI) marker. Using a Bayesian multi-locus species delimitation method, as well as single gene haplotype networks and gene trees, we delimit seven well supported cryptic species within the morphospecies L. rubellus, and confirm the split within the species-pair L. terrestris-L. herculeus. Limited hybridization was found between the most common species of L. rubellus (A) in northern Europe and two other species (B and H) in this complex, as well as between L. terrestris and L. herculeus. Deep mt divergence was found within L. terrestris s.str. but no support for further splitting of this taxon was found. Both L. rubellus and L. terrestris are well studied model organisms, and considering that cryptic species and hybridization were found within them, it is important that they are properly identified in future studies.
An aberrantly coloured male Golden Whistler Pachycephala pectoralis, lacking yellow pigment, is r... more An aberrantly coloured male Golden Whistler Pachycephala pectoralis, lacking yellow pigment, is reported from the Bellarine Peninsula, Victoria. This could be the first documented case of this colour aberration in the species.
DNA-barcoding, using the mitochondrial marker COI, has been found successful for the identificati... more DNA-barcoding, using the mitochondrial marker COI, has been found successful for the identification of specimens in many animal groups, but may not be suited for species discovery and delimitation if used alone. In this study, we investigate whether two observed COI haplogroups in the earthworm Aporrectodea longa correspond to two cryptic species or if the variation is intraspecific. This is done by complementing COI with two nuclear markers, ITS2 and Histone 3. The variation is studied using distance methods, parsimony networks and Bayesian coalescent trees, and the statistical distinctness of the groups is tested on gene trees using the genealogical sorting index, Rosenberg's PAB and Rodrigo et al.'s P(RD). We also applied multilocus species delimitation based on the multispecies coalescence model. The two haplogroups were found in COI, and all tests except P(RD) found them to be significantly distinct. However, in ITS2, the same groups were not recovered in any analyses or tests. H3 was invariable in A. longa, and was, therefore, included only in the multilocus analysis, which preferred a model treating A. longa as one species over a model splitting it into two. We also compared two measurements of size, body length, and no. of segments between the groups. No difference in body length was found, and although a significant difference in no. of segments was noted the haplogroup with the lower mean showed both the highest and the lowest value. When combined, these results led us to the conclusion that there is no support for the separation of A. longa into two cryptic species. This study again highlights the importance of complementing mitochondrial barcodes with more data when establishing species boundaries.
The five Nordic species of the genus Urytalpa Edwards (Diptera: Keroplatidae) are revised, of whi... more The five Nordic species of the genus Urytalpa Edwards (Diptera: Keroplatidae) are revised, of which one species, Urytalpa galdes Hedmark & Kjaerandsen, sp.n., is described as new to science based on males collected in northern Sweden. We find that the original type species assignment for Urytalpa (Platyura ochracea Meigen, 1818) is based on a misidentification, and in order to stabilize the nomenclature we therefore select a new type species, Urytalpa dorsalis (Staeger, 1840), sp. restit. A lectotype is designated for Orfelia ochracea (Meigen, 1818), comb. n. = Orfelia unicolor (Staeger, 1840), syn. n. The males of U. atriceps (Edwards, 1913), U. dorsalis, U. macrocera (Edwards, 1913) and U. trivittata (Lundström, 1914), and the females of U. dorsalis , U. macrocera and U. trivittata are described and illustrated based on Nordic material. As the first known Nearctic representative of Urytalpa, U. nigrita (Johannsen, 1910), comb. n., known from western USA Washington) and Canada, is ...
ABSTRACT Martinsson, S., Kjærandsen, J. & Sundberg, P. (2011). Towards a molecular phylog... more ABSTRACT Martinsson, S., Kjærandsen, J. & Sundberg, P. (2011). Towards a molecular phylogeny of the fungus gnat genus Boletina (Diptera: Mycetophilidae). —Zoologica Scripta, 40, 272–281.Boletina is a species rich genus of fungus gnats (Diptera: Mycetophilidae) with a mainly Holarctic distribution. The systematics within the genus has gained little attention and this is a first attempt to shed some light over the systematics of Boletina and to test the segregation of the genera Saigusaia and Aglaomyia from Boletina. The nuclear marker 28S and mitochondrial 16S, COI and CytB were amplified and sequenced for 23 taxa that were analysed separately and together with a broad sample of outgroup taxa obtained from GenBank, where also 18S sequences were added. Phylogenies were estimated using maximum likelihood, Bayesian inference and parsimony. We strengthen the hypothesized sister-group relationship between Docosia and Boletina, but the genus Boletina as currently delimited appears to be paraphyletic and nested in a clade together with Aglaomyia, Coelosia and Gnoriste. The genus Saigusaia, on the other hand, seems to be well separated from Boletina. The Boletina erythropyga species group is consistently found as a distinct basal clade within Boletina s.l. The results obtained are otherwise ambiguous both for the taxa in focus and in some analyses globally with a statistically supported total breakdown of the traditional higher classification into tribes, subfamilies and even families. Interestingly, this breakdown almost disappeared when additional 18S sequences were added.
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