The utility of isozymes in the systematics of some Australian tree groups

1990 ◽  
Vol 3 (1) ◽  
pp. 47 ◽  
Author(s):  
GF Moran ◽  
JC Bell ◽  
S Prober

The utility of isozyme analysis in elucidating the relationship between Australian tree taxa is reviewed. Although little exploited to date, isozyme analysis is shown to be a rapid and relatively powerful method of examining relationships, if used at an appropriate taxonomic level. For Eucalyptus and Acacia, isozymes appear to be the most informative at the lower taxonomic levels. In Eucalyptus delegatensis and Casuarina cunninghamiana, isozyme data strongly support subspecies erected on the basis of morphological characteristics. In Acacia holoserocea, isozyme data predicted the existence of two subspecies, which prediction as later supported by morphological characters. An isozyme study of the phylogenetic relationships within the 'green ash' group of eucalypts yielded a phylogenetic hypothesi comparable to one derived from morphological characters, but also highlighted areas of discrepancy requiring further research. At the generic level, isozyme data for the Australian species of Litsea and Neolitsea successfully separated the two genera and allowed phylogenetic relationships within genera to be hypothesised. For the larger tree genera such as the Eucalyptus and Acacia, however, the utility of isozymes at the higher taxonomic levels is likely to be low, because of the difficulty in establishing homologies between taxa, or insufficient phylogenetic information when taxa being compared have few alleles in common.

2020 ◽  
Vol 96 (2) ◽  
pp. 455-498
Author(s):  
Kai Horst George

Uncovering the systematics of CopepodaHarpacticoida, the second-most abundant component of the meiobenthos after Nematoda, is of major importance for any further research dedicated especially to ecological and biogeographical approaches. Based on the evolution of the podogennontan first swimming leg, a new phylogenetic concept of the Ancorabolidae Sars and Cletodidae T. Scott sensu Por (Copepoda, Harpacticoida) is presented, using morphological characteristics. It confirms the polyphyletic status of the Ancorabolidae and its subfamily Ancorabolinae Sars and the paraphyletic status of the subfamily Laophontodinae Lang. Moreover, it clarifies the phylogenetic relationships of the so far assigned members of the family. An exhaustive phylogenetic analysis was undertaken using 150 morphological characters, resulting in the establishment of a now well-justified monophylum Ancorabolidae. In that context, the Ancorabolus-lineage sensu Conroy-Dalton and Huys is elevated to sub-family rank. Furthermore, the membership of Ancorabolina George in a rearranged monophylum Laophontodinae is confirmed. Conversely, the Ceratonotus-group sensu Conroy-Dalton is transferred from the hitherto Ancorabolinae to the Cletodidae. Within these, the Ceratonotus-group and its hypothesised sister-group Cletodes Brady are combined to form a monophyletic subfamily Cletodinae T. Scott, subfam. nov. Consequently, it was necessary to restructure the Ancorabolidae, Ancorabolinae and Laophontodinae and extend the Cletodidae to include the displacement and exclusion of certain taxa. Moreover, comparison of the Ancorabolidae, Cletodidae, Laophontoidea and other Podogennonta shows that the Ancorabolidae and Cletodidae form sister-groups in a monophylum Cletodoidea Bowman and Abele, which similarly has a sister-group-relationship with the Laophontoidea T. Scott. According to the present study, both taxa constitute a derived monophylum within the Podogennonta Lang.


1967 ◽  
Vol 18 (5) ◽  
pp. 713 ◽  
Author(s):  
JS Gladstones

Ninety naturalized and four commercially introduced subterranean clover strains present in Western Australia were examined. Flowering time, hardseededness, contents of the oestrogenic isoflavones formononetin, genistein, and biochanin A, and plant morphological characteristics were measured in spaced plants. Probabilities of random relationships were calculated for all character pairs. Wide variation was found among strains for all characters measured. A number of strains had low oestrogenic isoflavone contents. Levels of the three isoflavones appeared to vary independently of each other and of all other characters. Hardseededness decreased with lateness of maturity, but evidence is adduced that the relationship was not causal. Correlations were recorded among several morphological characters. Some 20 naturalized, non-commercial strains were selected as worthy of further agronomic study.


Phytotaxa ◽  
2021 ◽  
Vol 482 (2) ◽  
pp. 121-142
Author(s):  
WEI GOU ◽  
XIAN-LIN GUO ◽  
SONG-DONG ZHOU ◽  
XING-JIN HE

Meeboldia H.Wolff, Sinodielsia H.Wolff and their relatives (Apiaceae: Apioideae) are similar in morphology, of which taxonomic treatments were controversial. In this study, the nuclear ribosomal DNA sequence (ITS) and two plastid DNA markers (rps16 and rpl16) were applied to reconstruct phylogenetic trees. The results demonstrated that Meeboldia and Sinodielsia formed a monophyletic group in phylogenetic trees and their highly similar morphological characteristics in taproot, basal leaves, calyx teeth, ribs, and vittae of fruits also confirmed their close relationships. Consequently, the following results were obtained: (1) Sinodielsia should be merged into Meeboldia; (2) Sinodielsia delavayi was confirmed conspecific with Meeboldia yunnanensis and renamed as Meeboldia delavayi (Franch.) W.Gou & X.J.He; (3) Sinodielsia thibetica was away from other Sinodielsia species; (4) Sinodielsia microloba was a member of Meeboldia and renamed as Meeboldia microloba (Kljuykov) W.Gou & X.J.He; (5) The name of Sinodielsia clade was suggested to be replaced by Hymenidium clade. We applied multiple approaches to explore the relationship of morphologically similar taxa, which will facilitate a deep understanding of taxonomy and species diversity of Apiaceae.


Phytotaxa ◽  
2021 ◽  
Vol 483 (3) ◽  
pp. 211-228
Author(s):  
SUZANA M. COSTA ◽  
FABIO A. VITTA ◽  
WILLIAM W. THOMAS ◽  
A. MUTHAMA MUASYA ◽  
ROSEMERI MOROKAWA ◽  
...  

Cryptangieae is a monophyletic tribe, as asserted in a recent molecular hypothesis, but there are questions about the circumscription and relationships of its genera. We enlarged the sampling of the tribe diversity, including about 80% of known species, and provide new analyses using single and combined matrices from two chloroplast (rbcL and trnL-F) and three nuclear ribosomal (ITS, ETS and 5S-NTS) regions with Bayesian Inference to clarify these questions. We also performed character reconstruction analyses with diagnostic morphological characters, including some traditionally applied in Cryptangieae taxonomy, using parsimony methods. The molecular analyses show Lagenocarpus in the current circumscription as polyphyletic, and the need to merge Cephalocarpus and Everardia to avoid paraphyletic genera. We propose an updated circumscription following the phylogeny, including a new name to a group at generic level (Krenakia); and discuss the phylogenetic significance of the morphological characters in Cryptangieae taxonomy. Though the relationship among some genera still needs more research, the genera we propose are strongly supported clades with clear morphological synapomorphies. Additionally, we provide an identification key, a brief description of genera and a list of accepted species including the required new combinations.


2001 ◽  
Vol 58 (2) ◽  
pp. 183-200 ◽  
Author(s):  
G. M. PLUNKETT

Phylogenetic relationships involving the angiosperm order Apiales (Apiaceae and Araliaceae) are troublesome at nearly every taxonomic level and have eluded several generations of botanists. Because of difficulties in interpreting and polarizing morphological character states at deeper phylogenetic levels, most studies in Apiales have focused on relationships between the two families and among/within the apialean genera. In the present study, however, recent contributions from molecular analyses are reviewed and combined using a ‘supertree’ approach to test traditional hypotheses of relationships involving Apiales, and to re-evaluate assumptions of character-state evolution in the order. Results from this study confirm that Apiales form a monophyletic group with Pittosporaceae (along with Griselinia G. Forst., Melanophylla Baker, Torricellia DC. and Aralidium Miq.), and should be transferred out of subclass Rosidae (away from both Cornales and Sapindales) to the Asteridae (in a position close to Asterales and Dipsacales). These findings are also supported by several lines of morphological, anatomical, and phytochemical evidence, and provide a more satisfactory framework for interpreting relationships and character-state evolution within the major clades of Apiales.


2008 ◽  
Vol 25 (2) ◽  
pp. 269-298 ◽  
Author(s):  
Tatiane R. Moreno ◽  
Rosana M. Rocha

The phylogenetic relationships of genera and families of Aplousobranchia Lahille (Tunicata, Ascidiacea) is reconstructed based on morphological characters - the first comprehensive morphology-based phylogenetic analysis for the Aplousobranchia. Monophyly of Aplousobranchia and its families were tested with samples of 14 families. The final character matrix comprised 47 characters and 41 genera as terminal taxa. Nine equally most parsimonious trees (length 161, CI = 0.5031, RI = 0.7922) were found. Characters describing replication, colony system formation, and branchial walls were the more important in phylogenetic reconstruction. These characters were more useful than others more traditionally used in ascidian taxonomy, such as: body division, position of the heart, gonads and epicardium. Characters not frequently used in phylogenetic analysis, such as body wall muscles, muscles associated with transversal blood vessels and arrangement of the larval papillae, also have phylogenetic information. Results supported monophyly of the Aplousobranchia sensu Lahille, 1887 including only Polycitoridae, Polyclinidae, and Didemnidae. On the other hand, Aplousobranchia including also Cionidae and Diazonidae is not monophyletic since Perophora and Ecteinascidia were included as ingroups in the cladogram, Ciona (now closer to Ascidia) was no longer included in Aplousobranchia and the position of Rhopalaea and Diazona is not resolved. We propose a revised classification based on this phylogenetic analysis, in which Aplousobranchia, with three new families and an indeterminate taxon, now has 15 families.


2018 ◽  
Vol 30 (1-2) ◽  
pp. 32-48
Author(s):  
M. Louail ◽  
S. Prat

The standard ASUDAS scoring system (Arizona State University Dental Anthropology System) is used to assess dental morphological variations in modern humans. It is also frequently used to study, score, and compare morphological variations in fossil hominin taxa and to examine their phylogenetic relationships. However, using ASUDAS in studies of this type is under debate because it is based on modern Homo sapiens populations and does not appear to cover all variations observed in fossil Plio-Pleistocene homi- nins. Our observations and coding of 178 dentals casts of Plio-Pleistocene specimens based on ASUDAS and from the literature have confirmed the need to adapt the standard system to fossil hominins. In this initial study, we propose that the scoring procedures for some morphological characters need to be readjusted, while others could be standardized following the ASUDAS system.


Distant hybridization is known to play an important role in expanding the gene pool of any crop. It is believed that the combination of different genomes in one nucleus, as a rule, is accompanied by the phenomenon of “genomic shock”, resulting in a variety of genetic and epigenetic changes. This provides a wealth of material for the selection of genotypes adapted to different environmental conditions. Interspecific hybrids in different combinations were obtained in the genus Brassica, however, until now, interest in distant hybridization in this genus has not died out, since such important crops as rapeseed and mustard demand an improvement of many important agronomic traits. The aim of this work was to study the degree of manifestation of morphological characters of a leaf, flower, and plant as a whole in the hybrid obtained by crossing of brown mustard of the variety Slavyanka and a collection specimen of spring rape. Seeds were sown in the spring of 2019 in a field with 30 cm row width. During the flowering period a number of morphological characters of a flower, leaf, and the whole plant were analyzed. Each parameter was evaluated with 10 plants. The degree of dominance in first-generation hybrid was calculated by the formula of Beil, Atkins (1965). The dominance coefficients were not determined in the case when the difference between the parental samples was insignificant. Differences between parental samples were determined by Student t-test. The level of heterosis was calculated according to the formula of Rasul et al (2002). In a mustard-rapeseed hybrid, the size of the leaves of the lower row was inherited by the type of rapeseed, which had larger leaves than mustard. The height of the hybrid plant was inherited by the type of mustard (hp = 1.32, Ht = 4.89%), and intermediate inheritance was observed for the length of the internodes (hp = -0.48). The size of the flower petals and sepals was inherited by the type of rapeseed, and significant heterosis was observed for the length of the pistil (Ht = 33.57%). The data obtained are of interest for understanding the interaction of genes of different genomes in the genus Brassica.


2005 ◽  
Vol 26 (2) ◽  
pp. 139-147 ◽  
Author(s):  
Francisca do Val ◽  
Paulo Nuin

AbstractThe systematics and phylogenetic relationships of the family Leptodactylidae are controversial as is the intrafamilial phylogeny of the leptodactylids. Here we analyze the relationships of the leptodactylid subfamily Hylodinae. This subfamily has been considered to be monophyletic and composed of three genera, Hylodes, Crossodactylus and Megaelosia. In the present study 49 characters were used, based on different studies on Leptodactylidae phylogeny. Maximum parsimony methods with unweighted and successively weighted characters were used to estimate the phylogeny of the Hylodinae. Upon analysis, the data provided further evidence of the monophyletic status of the three genera, with Megaelosia being the basal genus and the other two genera being sister taxa. The analysis with successive weighting results in a more resolved topology of the species subgroups of the genus Hylodes and separates this genus from Crossodactylus and confirms that the hylodines are monophyletic.


2007 ◽  
Vol 139 (3) ◽  
pp. 297-307 ◽  
Author(s):  
Željko Tomanović ◽  
Ehsan Rakhshani ◽  
Petr Starý ◽  
Nickolas G. Kavallieratos ◽  
Ljubiša Ž. Stanisavljević ◽  
...  

AbstractWe analyzed the phylogenetic relationships between eight Aphidius Nees and six Lysaphidus Smith species on the basis of 12 morphological characters by parsimony analysis. The consensus tree does not support the generic status of Lysaphidus. Aphidius iranicus, sp. nov., associated with Titanosiphon bellicosum Nevsky on Artemisia absinthium L. from Iran, is described. The new parasitoid species is described and illustrated by line drawings, and its diagnostic characters are discussed. The taxonomic position of the subgenus Tremblayia Tizado and Núñez-Pérez is also considered. Tremblayia and Lysaphidus are newly classified as synonyms of Aphidius. The following new or revised combinations are proposed: Aphidius adelocarinus Smith, comb. rev., A. ramythirus Smith, comb. rev., A. rosaphidis Smith, comb. rev., A. viaticus (Sedlag), comb. nov., A. arvensis (Starý), comb. nov., and A. erysimi (Starý), comb. nov.


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