MétaCan
Menu
Back to cohort
Record W2901503511 · doi:10.11646/phytotaxa.376.6.2

Sansevieria (Asparagaceae, Nolinoideae) is a herbaceous clade within Dracaena: inference from non-coding plastid and nuclear DNA sequence data

2018· article· en· W2901503511 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenuePhytotaxa · 2018
Typearticle
Languageen
FieldBiochemistry, Genetics and Molecular Biology
TopicPhytochemical Studies and Bioactivities
Canadian institutionsCanadian Museum of NatureUniversity of Ottawa
FundersRoyal Botanical Gardens, Kew
KeywordsBiologyMonophylyParaphylyCladeNdhFPhylogenetic treeBotanyMaximum parsimonyChloroplast DNAEvolutionary biologyPhylogeneticsGeneticsGene

Abstract

fetched live from OpenAlex

The evolutionary history of the dracaenoid genera Dracaena and Sansevieria (Asparagaceae, Nolinoideae) remains poorly resolved, despite long-recognised issues with their generic boundaries and increased attention paid by both horticulturalists and taxonomists. In this study we aim to: (1) elucidate evolutionary relationships within and between Dracaena and Sansevieria using molecular phylogenetic inference of both nuclear (nDNA) and plastid (cpDNA) markers, (2) examine the infrageneric classifications of each genus, and (3) revise the circumscription of the dracaenoids in light of morphological and phylogenetic evidence. In total, we sampled 21 accessions of Dracaena (ca. 19 species), 27 accessions of Sansevieria (ca. 26 species), and six outgroup taxa. Phylogenetic analyses were based on nucleotide sequences of two non-coding plastid DNA regions, the trnL-F region (trnL intron and trnL-trnF intergenic spacer) and rps16 intron, and the low-copy nuclear region At103. Phylogenetic hypotheses were constructed using maximum parsimony, maximum likelihood, and Bayesian inference. Individual datasets were analysed separately and, after testing for congruence, as combined datasets. We recovered instances of soft incongruence between nDNA and cpDNA datasets in Sansevieria, but general trends in the dracaenoids were congruent, although often poorly supported or resolved. The dracaenoids constitute a strongly supported monophyletic group. Dracaena was resolved as a paraphyletic grade embedded with two clades of Sansevieria, a primary clade comprising most species, and a secondary clade including S. sambiranensis, a distinctive species from Madagascar. The backbone of our phylogeny was only resolved in nDNA analyses, but combined analyses recovered strongly supported species groups. None of the previous infrageneric classifications were supported by our phylogeny, and biogeographic groupings were frequently more significant than morphology. More work is needed to resolve internal relationships in the dracaenoids, but we support a recent proposal to recognise a broadened circumscription of Dracaena that includes Sansevieria. We provide a generic description for the recircumscribed Dracaena and new combinations for several species of Sansevieria in Dracaena.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.115
Threshold uncertainty score0.963

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.001
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0000.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.040
GPT teacher head0.295
Teacher spread0.255 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it