Topic
Axinandra
About: Axinandra is a research topic. Over the lifetime, 13 publications have been published within this topic receiving 450 citations.
Papers
TL;DR: Crypteroniaceae are the first plant group for which the out-of-India hypothesis is well corroborated by molecular-based estimates of divergence times and are also the first to be identified as a sister to a clade formed by three small African taxa.
Abstract: Phylogenetic analyses and molecular dating estimates based on chloroplast DNA sequences were used to establish the relationships of the southern and Southeast Asian Crypteroniaceae and elucidate their biogeographic history. Maximum parsimony and likelihood analyses of rbcL sequences suggested that Crypteroniaceae should be restricted to Crypteronia, Axinandra, and Dactylocladus and that Crypteroniaceae, so defined, are sister to a clade formed by three small African taxa (Oliniaceae, Penaeaceae, and Rhynchocalycaceae) and the monotypic Central and South American Alzateaceae. Three molecular dating approaches (maximum-likelihood under a molecular clock, Langley-Fitch, and penalized-likelihood) were used to infer the age of Crypteroniaceae using both paleobotanic and geologic calibrations. Comparisons among these three methods revealed significant lineage effects in rbcL sequences. Clock-independent dating estimates suggested that divergence of Crypteroniaceae from its African and South American relatives coincided with the breakup of Gondwana, and that India likely served as a "raft" transporting Crypteroniaceae to Asia, with later expansion to Southeast Asia. To our knowledge, Crypteroniaceae are the first plant group for which the out-of-India hypothesis is well corroborated by molecular-based estimates of divergence times.
174 citations
TL;DR: Dating results indicate an ancient Gondwanan origin of Crypteroniaceae in the early to Middle Cretaceous, followed by diversification on the Indian plate in the Early Tertiary and subsequent dispersal to Southeast Asia.
Abstract: Biogeographical and paleontological studies indicated that some ancient Gondwanan taxa have been carried by the rafting Indian plate from Gondwana to Asia. During this journey, the Indian island experienced dramatic latitudinal and climatic changes that caused massive extinctions in its biota. However, some taxa survived these conditions and dispersed “out of India” into South and Southeast Asia, after India collided with the Asian continent in the Early Tertiary. To test this hypothesis, independent estimates for lineage ages are needed. A published rbcL tree supported the sister group relationship between the South and Southeast Asian Crypteroniaceae (comprising Crypteronia, Axinandra, and Dactylocladus) and a clade formed by the African Oliniaceae, Penaeaceae, and Rhynchocalycaceae and the Central and South American Alzateaceae. Molecular dating estimates indicated that Crypteroniaceae split from their West Gondwanan sister clade in the Early to Middle Cretaceous and reached Asia by rafting on the Indi...
81 citations
Journal Article•
TL;DR: A new delimitation and subdivision of the Crypteroniaceae (Myrtales) is given; no less than five genera, Crypteronia, Dactylocladus, Axinandra, Alzatea, and Rhynchocalyx are included.
Abstract: A new delimitation and subdivision of the Crypteroniaceae (Myrtales) is given; no less than five genera, Crypteronia, Dactylocladus, Axinandra (all SE. Asia), Alzatea (S. America), and Rhynchocalyx (S. Africa) are included. Traditionally the Crypteroniaceae were considered to be a monotypic family. The family is subdivided into two subfamilies, Crypteronioideae and Alzateoideae, the subfamilies each into two tribes, and some of the genera into sections. Of these taxa descriptions, synonymy, references, and notes on distribution and ecology are given, as well as a key for their identification. Of the species recognized only names, typification, synonyms, and distribution are briefly mentioned. In Crypteronia one new species, C. macrophylla, is described. Argumentation for the present taxonomical treatment is given in a separate article in the next issue (Van Beusekom, 1975).
36 citations
TL;DR: Comparisons with some other Myrtalean families indicate intimate relationships between Melastomataceae, Lythraceae, Oliniaceae, Sonneratiaceae and Crypteroniaceae s.l. because of overlapping of the wood anatomical range among these families.
Abstract: SUMMARY
The wood anatomy of Alzatea from South America, Axinandra, Crypteronia and Dactylocladus from South East Asia, and Rhynchocalyx from South Africa is described in detail. Special attention has been given to the ultrastructure of vestured pits in the five genera. The grouping of these genera into one family as suggested recently is not supported by wood anatomy. Alzatea andRhynchocalyx differ widely from the three other genera and appear to share many characters with both Lythraceae and Melastomataceae; the latter family shows a wide wood anatomical range. The wood anatomical affinities of Axinandra, Crypteronia and Dactylocladus are with Melastomataceae. Comparisons with some other Myrtalean families, notably Oliniaceae and Sonneratiaceae, indicate intimate relationships between Melastomataceae, Lythraceae, Oliniaceae, Sonneratiaceae and Crypteroniaceae s.l. because of overlapping of the wood anatomical range among these families.
35 citations
Journal Article•
TL;DR: It is argued that the heterocolpate type found in Dactylocladus, Axinandra, and Rhynchocalyx and the bisyncolporate type characterizing Crypteronia, may both have been derived from a less-specialized tricolpate ancestral type which has been retained in Alzatea.
Abstract: The pollen morphology of the genera Crypteronia, Dactylocladus, Axinandra, Alzatea and Rhynchocalyx is compared in view of a proposal to unite these genera in Crypteroniaceae. Three pollen types are recognized, differing in aperture and shape symmetry, but showing distinct similarities in exine and aperture structure. It is argued that the heterocolpate type found in Dactylocladus, Axinandra, and Rhynchocalyx and the bisyncolporate type characterizing Crypteronia, may both have been derived from a less-specialized tricolpate ancestral type which has been retained in Alzatea. The wider affinities of Crypteroniaceae are discussed and thought to be with Lythraceae and Melastomataceae, although a more remote relationship with Cunoniaceae s also possible.
33 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2016 | 1 |
| 2004 | 1 |
| 2002 | 1 |
| 1987 | 2 |
| 1984 | 3 |
| 1983 | 1 |