Clinal Variation in Electrophoretic and Morphological Characters between Two Nominal Species of the Genus Pseudomugil (Pisces : Atheriniformes : Pseudomugilidae)

1979 ◽  
Vol 30 (3) ◽  
pp. 375 ◽  
Author(s):  
AJ Hadfield ◽  
V Ivantsoff ◽  
PG Johnson
Keyword(s):  
Principal Components ◽  
Major Part ◽  
Single Species ◽  
Morphological Characters ◽  
Morphological Data ◽  
Nominal Species ◽  
Clinal Variation ◽  
Brackish Waters ◽  
Coastal Species ◽  
Eastern Australia

Electrophoretic and morphological comparisons were made between 14 populations representing the major part of the known range of the nominal fish species, Pseudomugil signifer Kner and Pseudomugil signatus (Gunther), described from the fresh and brackish waters of eastern Australia. Analysis by principal components was used to assess the morphological data. .Clinal variation revealed in 10 morphological characters and at two enzyme loci was found to bridge most of the previously described differences between species. The type material of P. signatus afinis from the Low Isles, Queensland, was re-examined and did not appear to differ morphologically from the coastal species. It is therefore suggested that the populations studied represent a single species Pseudomugil signifer Kner.

Revision of Autolytinae (Syllidae: Polychaeta)

Zootaxa ◽  
2004 ◽  
Vol 680 (1) ◽  
pp. 1 ◽  
Author(s):  
ARNE NYGREN
Keyword(s):  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Data Sets ◽  
Nominal Species ◽  
Strict Consensus Tree ◽  
Incertae Sedis ◽  
Nomina Dubia ◽  
Morphological And Molecular Data ◽  
Combined Data

Autolytinae is revised based on available types, and newly collected specimens. Out of 170 nominal species, 18 are considered as incertae sedis, 43 are regarded as junior synonyms, and 25 are referred to as nomina dubia. The relationships of Autolytinae is assessed from 51 morphological characters and 211 states for 76 ingroup-taxa, and 460 molecular characters from mitochondrial 16S rDNA and nuclear 18S rDNA for 31 ingroup-taxa; outgroups include 12 non-autolytine syllid polychaetes. Two analyses are provided, one including morphological data only, and one with combined morphological and molecular data sets. The resulting strict consensus tree from the combined data is chosen for a reclassification. Three main clades are identified: Procerini trib. n., Autolytini Grube, 1850, and Epigamia gen. n. Proceraea Ehlers, 1864 and Myrianida Milne Edwards, 1845 are referred to as nomen protectum, while Scolopendra Slabber, 1781, Podonereis Blainville, 1818, Amytis Savigny, 1822, Polynice Savigny, 1822, and Nereisyllis Blainville, 1828 are considered

Population Studies on Acacia melanoxylon R. Br. I. Variation in Seed and Vegetative Characteristics

1978 ◽  
Vol 26 (3) ◽  
pp. 365 ◽  
Author(s):  
TP Farrell ◽  
DH Ashton
Keyword(s):  
Environmental Parameters ◽  
Morphological Characters ◽  
Annual Rainfall ◽  
Clinal Variation ◽  
Acacia Melanoxylon ◽  
Open Forest ◽  
Popu Lations ◽  
Eastern Australia ◽  
Closed Forest ◽  
Shape And Size

Considerable variation in phyllode shape and size was found between populations of Acacia melanoxylon sampled over the wide geographical range (27° of latitude) of this species in tropical and temperate eastern Australia. Communities sampled range from closed-forest to open-forest and grassy woodland. Some evidence of relationships between morphological characters of the phyllodes and environ- mental conditions of the collecting site was found, although such relationships are complex and not easily understood. The most important factors determining phyllode shape and size were the distance of the collecting site from the coast, and the seasonal distribution of the annual rainfall. Phyllodes tended to be smaller and more symmetric in the drier inland areas. Differences were found between seed characteristics of selected populations, although there was no evidence of correlation of these with selected environmental parameters. Seedlings of 17 popu- lations of A. melanoxylon grown under uniform glasshouse conditions showed some differences in leaf morphology. The age at which conversion to phyllodes begins is correlated with the mean annual rainfall at the site of origin of the seeds. The occurrence of this species in such a wide variety of habitats in eastern Australia is probably due to its clinal variation.

Taxonomy of Moenkhausia australis Eigenmann, 1908 (Characiformes, Characidae) with a discussion on its phylogenetic relationships

Zootaxa ◽  
2019 ◽  
Vol 4688 (2) ◽  
pp. 213-231 ◽  
Author(s):  
LAIS REIA ◽  
ANA MARIA P. F. VICENSOTTO ◽  
CLAUDIO OLIVEIRA ◽  
RICARDO C. BENINE
Keyword(s):  
Lateral Line ◽  
Single Species ◽  
Morphological Characters ◽  
Color Pattern ◽  
Structured Populations ◽  
The Other ◽  
Morphological Data ◽  
Genetic Lineages ◽  
Taxonomic History ◽  
Rio Madeira

The species Moenkhausia australis was described based on two specimens from arroyos Trementina and Chagalalina, Rio Paraguai basin, Paraguay. Its taxonomic history is complex and for many years the species was considered a synonym of Moenkhausia sanctaefilomenae. Moenkhausia australis shares a reticulated color pattern with the Moenkhausia oligolepis/M. sanctaefilomenae complex, being more similar within the species included in the complex to M. oligolepis, M. sanctaefilomenae, and M. forestii, with which it shares a prepelvic region laterally compressed, a feature also observed in Bario steindachneri. The laterally compressed prepelvic region is inferred to be putatively synapomorphic for the subgroup herein denominated as Moenkhausia oligolepis group. Our results, based on both molecular and morphological data, support the validity of Moenkhausia australis, which can be readily distinguished from the other members of the group by possessing the following combination of characters: complete lateral line, 23–27 scales in the lateral line, and five scales series above and below the lateral line. Our analysis also indicates three genetic structured populations of M. australis, from Rio Paraguai, upper Rio Paraná, and Rio Madeira basins. Since they are not diagnosable by morphological characters, we conservatively maintain these three genetic lineages as a single species. 

The genealogy of geebungs: phylogenetic analysis of Persoonia (Proteaceae) and related genera in subfamily Persoonioideae

2018 ◽  
Vol 31 (2) ◽  
pp. 166
Author(s):  
Gareth D. Holmes ◽  
Peter H. Weston ◽  
Daniel J. Murphy ◽  
Carolyn Connelly ◽  
David J. Cantrill
Keyword(s):  
Western Australia ◽  
New Caledonia ◽  
Plastid Dna ◽  
Morphological Characters ◽  
Molecular Data ◽  
Morphological Data ◽  
Rdna Its ◽  
Eastern Australia ◽  
Group Relationships ◽  
Informal Groups

Proteaceae subfamily Persoonioideae, as presently circumscribed, consists of the monogeneric tribe Placospermeae (Placospermum) and the tribe Persoonieae. The latter comprises the diverse genus Persoonia and monospecific genera found in New Zealand (Toronia), New Caledonia (Garnieria) and south-western Western Australia (Acidonia). Persoonia has 101 species distributed across Australia and has been classified into 11 informal groups. Using data derived from plastid DNA (trnL–trnF region), nuclear rDNA (ITS) and morphological characters, we constructed a phylogeny of Persoonioideae and compared the results to the existing classification. Bayesian and parsimony analyses indicated that Persoonia, as currently defined, is non-monophyletic. The molecular data and combined molecular and morphological data place Toronia in a moderately well supported clade with the monophyletic Rufiflora group of Persoonia from Western Australia. This clade is sister to Acidonia, Garnieria and the remaining Persoonia species. Of the other informal groups in Persoonia, the Teretifolia, Quinquenervis, Laurina, Arborea, Graminea and Chapmaniana groups are supported as monophyletic. The Lanceolata group can be re-circumscribed to be monophyletic by the addition of P. elliptica R.Br. (Longifolia group) and the Dillwynioides group. Relationships within this large, geographically widespread clade are largely unresolved and low DNA-sequence variation within it suggests a recent radiation followed by isolation in south-western and eastern Australia. All endemic Tasmanian Persoonia (Gunnii group taxa) are unresolved at the second-most basal node of the Persoonieae. Our results suggest that the Rufiflora group should be treated as a new genus and that the infrageneric taxonomy of Persoonia requires minor amendment.

scholarly journals The taxonomic status of Tilia dasystyla in Crimea, Ukraine

1999 ◽  
Vol 56 (2) ◽  
pp. 161-173 ◽  
Author(s):  
C. D. Pigott ◽  
B. Francis
Keyword(s):  
Logistic Regression ◽  
Principal Components ◽  
Taxonomic Status ◽  
Single Species ◽  
Morphological Characters ◽  
Herbarium Specimens ◽  
Chromosome Counts ◽  
The Caucasus ◽  
Fresh Material ◽  
Components Analysis

Nine populations of Tilia dasystyla Steven (Tiliaceae) in the Crimean mountains (Krymskiye Gory), including the type locality at Kastel Dag, were studied in the field and sampled by collection of herbarium specimens. This material was compared with specimens referred to Tilia hegonifolia Steven collected in Crimea, the Caucasus and Iran. Measurements or scores of 21 morphological characters made on the dried material were analysed by principal components analysis and logistic regression. These analyses demonstrated that the majority of trees could be correctly allocated to either Crimea or the Caucasus and Iran on the basis of the shape of their leaves and the area of their bracts. In addition there are differences of leaf and bract texture and bract colour which can be observed in fresh material. Chromosome counts showed that Crimean trees and one Caucasian tree are tetraploid (2n = 164). It is proposed that the Crimean, Caucasian and Iranian trees be treated as a single species with at least two subspecies: Tilia dasystyla Steven subsp. dasystyla from Crimea and T. dasystyla Steven subsp. caucasica (V. Engl.) Pigott from the Caucasus and Iran.

Cryptic species diversity and character congruence: review of the tribe Anthracini (Diptera : Bombyliidae) in Australia

1998 ◽  
Vol 12 (6) ◽  
pp. 977 ◽  
Author(s):  
David K. Yeates ◽  
Christine L. Lambkin
Keyword(s):  
New Species ◽  
Cryptic Species ◽  
Cladistic Analysis ◽  
Morphological Characters ◽  
Species Group ◽  
Morphological Data ◽  
Distribution Maps ◽  
Eastern Australia ◽  
Wing Patterns ◽  
Species Groups

The Australian Anthracini are revised. In all, 28 new species are described, bringing the total fauna to 34 species. The previously described species of Anthrax Scopoli – A. maculatus Macquart, A. incomptus Walker, A. confluensisRoberts, A. lepidiotus Roberts and A. proconcisus Hardy – are diagnosed and the following eight new species of Anthrax are described: A. argentia, A. asciculus, A. clinatus, A. crenatus, A. dolabratus, A. funestus, A. opacus and A. torulus. This taxonomic study reveals a group of at least 20 cryptic species previously included in collections under the name Anthrax angularis Thomson. A new genus, Thraxan, is erected to contain this cryptic group of species and the following 20 new species are described: T. acutus, T. abditus, T. caligneus, T. cinctus, T. cornuatus, T. depressus, T. echinatus, T. ebenus, T. emicatus, T. hamulus, T. luteus, T. misatulus, T. nodus, T. norrisi, T. obstipus, T. patielus, T. planus, T. prolatus, T. simulatusand T. spiculus. Many of these cryptic species have been collected sympatrically, hill topping together in eastern Australia. A key is provided to the species of Anthrax and Thraxan, genitalia drawings are presented for most species and distribution maps of all species are presented. A cladistic analysis of the species of Anthrax and Thraxan is also presented. A total of 26 of the species is compared for 125 synapomorphies in 39 adult morphological characters. Three species-groups were found: Thraxan, and two species-groups within Anthrax, the A. proconcisus species-group and the A. maculatusspecies-group. Previous authors divided Anthrax into species-groups on the basis of wing patterns, but found that these species-groups were not confirmed when other characters were taken into consideration. We studied the congruence of seven different character sets within the clade comprising Anthrax and Thraxan – antennae, venation, wing patterns, vestiture, genitalia, male genitalia and female genitalia – using several incongruence indices. Significance of incongruence was measured using a randomisation procedure. Results of these studies indicate that the wing-pattern character set is significantly incongruent with the other morphological data. These quantitative cladistic results explain the difficulty previous authors experienced in finding suites of characters to support species-groups in Anthrax on the basis of wing patterns. A relationship is found between the level of incongruence and the distance over which mate-recognition signals operate.

scholarly journals Geopolitical species revisited: genomic and morphological data indicate that the roundtail chubGila robustaspecies complex (Teleostei, Cyprinidae) is a single species

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5605 ◽  
Author(s):  
Joshua M. Copus ◽  
W. L. Montgomery ◽  
Zac H. Forsman ◽  
Brian W. Bowen ◽  
Robert J. Toonen
Keyword(s):  
Single Species ◽  
Molecular Data ◽  
Morphological Data ◽  
Nominal Species ◽  
Type Specimens ◽  
Climate Conditions ◽  
Management Plans ◽  
Tree Topologies ◽  
Wet And Dry Cycles ◽  
Tree Building

TheGila robustaspecies complex in the Lower Colorado River Basin has a complicated taxonomic history. Recent authors have separated this group into three nominal taxa,G. robusta,G. intermedia, andG. nigra, however aside from location, no reliable method of distinguishing individuals of these species currently exists. To assess relationships within this group, we examined morphology of type specimens and fresh material, and used RADseq methods to assess phylogenetic relationship among these nominal species. Maximum likelihood and Bayesian inference tree building methods reveal high concordance between tree topologies based on the mitochondrial and nuclear datasets. Coalescent SNAPP analysis resolved a similar tree topology. Neither morphological nor molecular data reveal diagnostic differences between these species as currently defined. As such,G. intermediaandG. nigrashould be considered synonyms of the seniorG. robusta. We hypothesize that climate driven wet and dry cycles have led to periodic isolation of population subunits and subsequent local divergence followed by reestablished connectivity and mixing. Management plans should therefore focus on retaining genetic variability and viability of geographic populations to preserve adaptability to changing climate conditions.

A revision of the Australian taxa previously attributed to Assiminea buccinoides (Quoy & Gaimard) and Assiminea tasmanica Tenison-Woods (Mollusca:Gastropoda:Caenogastropoda:Assimineidae)

2005 ◽  
Vol 19 (4) ◽  
pp. 325 ◽  
Author(s):  
Hiroshi Fukuda ◽  
Winston F. Ponder
Keyword(s):  
New Genus ◽  
Cladistic Analysis ◽  
River Estuary ◽  
South Australia ◽  
Single Species ◽  
Morphological Characters ◽  
South Eastern ◽  
Eastern Australia ◽  
Species Groups ◽  
Western Victoria

A new genus, Cryptassiminea, is introduced for the taxon previously known as Assiminea buccinoides (Quoy & Gaimard). These small gastropods are abundant in mangrove and salt marsh habitats in south-eastern and subtropical eastern Australia. Seven species (five new) are recognised using morphological characters in the complex previously treated as a single species. Five taxa have rather narrow ranges while the other two are widespread and often sympatric. Two groups of species are recognised. One contains Cryptassiminea buccinoides, widespread in south-east and east Australia, and two closely related allopatric taxa from South Australia and south-eastern Tasmania (C. adelaidensis, sp. nov. and C. kershawi, sp. nov.). A second group of species is typified by Cryptassiminea tasmanica (Tenison-Woods), also widespread in east and south-east Australia and often sympatric with C. buccinoides. Allied to C. tasmanica, are two closely related taxa from western Victoria: C. glenelgensis, sp. nov. from the Glenelg River estuary and C. surryensis, sp. nov. from the Surry River estuary and Western Port, in the vicinity of Geelong. A distinctive species, Cryptassiminea insolata, sp. nov. from the east coast of Queensland, also has similarities with C. tasmanica. A cladistic analysis using morphological characters of the Cryptassiminea taxa and three other genera of Assimininae, with an omphalotropidine as the outgroup, resulted in a single tree. The new genus has rather poor support, possibly because many of its characters appear to be plesiomorphic within Assimineinae. Cryptassiminea is defined by a unique combination of characters but lacks any obvious synapomorphy. Two clades within Cryptassiminea are well supported, each containing the species-groups referred to above.

Phylogenetic analysis of Eucalyptus informal subgenus Symphyomyrtus section Maidenaria

1996 ◽  
Vol 9 (1) ◽  
pp. 71 ◽  
Author(s):  
JA Chappill ◽  
PY Ladiges
Keyword(s):  
Phylogenetic Analysis ◽  
Phylogenetic Relationships ◽  
Morphological Characters ◽  
Morphological Data ◽  
Approximate Representation ◽  
Oil Glands ◽  
Data Set ◽  
Eastern Australia ◽  
Pattern Of Variation ◽  
High Level

Eucalyptus informal subgenus Symphyomyrtus section Maidenaria includes 86 currently recognised taxa endemic to south-eastern Australia. Cladistic methodology and a morphological data set have been used to examine the phylogenetic relationships of these taxa and an additional two unnamed forms that may be worthy of taxonomic recognition. Maidenaria may be defined as a monophyletic group by the presence of oil glands in the phloem, although this feature is not unique to the group. Informal series Ovatae is paraphyletic, having been defined by plesiomorphic features such as petiolate juvenile leaves. Informal series Vitninales is monophyletic, defined by juvenile leaves that are opposite, sessile and cordate for many nodes. The analysis was a difficult one because of a high level of homoplasy (82%), problems with intergrading complexes of taxa, and coding of characters that are continuously varying. The cladogram produced for Maidenaria can be viewed as a statement of the pattern of variation of morphological characters in the group. It is likely to be only an approximate representation of the phylogeny due to problems of character coding.

Morphological and molecular characterisation of Panagrellus spp. (Cephalobina: Panagrolaimidae): taxonomic status and phylogenetic relationships

Nematology ◽  
2006 ◽  
Vol 8 (6) ◽  
pp. 921-938 ◽  
Author(s):  
S. Patricia Stock ◽  
Steven Nadler
Keyword(s):  
Sequence Data ◽  
Principal Component ◽  
Taxonomic Status ◽  
Single Species ◽  
Morphological Characters ◽  
Morphological Data ◽  
Lsu Rdna ◽  
Type Specimens ◽  
Worldwide Distribution ◽  
Tree Topologies

AbstractThe genus Panagrellus currently comprises 12 known species. These nematodes have a worldwide distribution and have been found in a variety of habitats such as slime flux, thermal springs, insect frass and spoiled cider. Diagnosis of Panagrellus species is rather problematic since few morphological features can be used to discriminate between species and the original publications do not indicate the number of specimens measured and lack standard descriptions of variance. In this study we review the taxonomic status of several species from this genus combining classical morphological data and molecular sequences. Eleven live isolates and fixed material from currently available type specimens representing six Panagrellus species were included. Morphological analysis included the examination of qualitative and quantitative characters of males and females. The taxonomic utility of morphometric data was evaluated by means of multivariate statistics (principal component and canonical discriminant analyses). Phylogenetic inference was based on analysis of nucleotide sequences from the LSU rDNA gene and morphological characters. Parsimony tree topologies inferred from nucleotide datasets strongly supported monophyly of the P. dubius isolates, but not the P. redivivus isolates. Phylogenetic interpretation of these rDNA sequence data suggests that both the P. redivivus and P. dubius isolates each include more than a single species. Only two of the 15 morphological characters evaluated were variable within the ingroup taxa. A long spicule bifurcation length maps on the combined evidence trees as a putative synapmorphy for P. dubius, whereas male D% was homoplastic within isolates of that species. The diagnosis of the genus Panagrellus is emended.

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