TY  - JOUR
A1  - Kocyan, Alexander
A1  - Snijman, Deirdre A.
A1  - Forest, Felix
A1  - Devey, Dion S.
A1  - Freudenstein, John V.
A1  - Wiland-Szymanska, Justyna
A1  - Chase, Mark W.
A1  - Rudall, Paula J.
T1  - Molecular phylogenetics of Hypoxidaceae - Evidence from plastid DNA data and inferences on morphology and biogeography
JF  - Molecular phylogenetics and evolution
N2  - Phylogenetic relationships of the monocot family Hypoxidaceae (Asparagales), which occurs mainly in the Southern Hemisphere, were reconstructed using four plastid DNA regions (rbcL, trnL intron, trnL-F intergenic spacer, and trnS-G intergenic spacer) for 56 ingroup taxa including all currently accepted genera and seven species of the closely related families Asteliaceae, Blandfordiaceae, and Lanariaceae. Data were analyzed by applying parsimony, maximum likelihood and Bayesian methods. The intergenic spacer trnS-G - only rarely used in monocot research - contributed a substantial number of potentially parsimony informative characters. Hypoxidaceae consist of three well-supported major clades, but their interrelationships remain unresolved. Our data indicate that in the Pauridia clade one long-distance dispersal event occurred from southern Africa to Australia. Long-distance dispersal scenarios may also be likely for the current distribution of Hypoxis, which occurs on four continents. In the Curculigo clade, the present distribution of Curculigo s.s. on four continents could support a Gondwanan origin, but the level of divergence is too low for this hypothesis to be likely. The main clades correspond well with some floral characters, habit and palynological data, whereas chromosomal data exhibit plasticity and probably result from polyploidization and subsequent dysploidy and/or aneuploidy. Evolutionary flexibility is also suggested by the number of reported pollination syndromes: melittophily, myophily, sapromyophily, and cantharophily. Based on our phylogenetic results, we suggest cautious nomenclatural reorganization to generate monophyly at the generic level.
KW  - Asparagales
KW  - Phylogenetics
KW  - Biogeography
KW  - Character evolution
KW  - Pollination syndromes
KW  - trnS-G spacer
Y1  - 2011
U6  - https://doi.org/10.1016/j.ympev.2011.02.021
SN  - 1055-7903
VL  - 60
IS  - 1
SP  - 122
EP  - 136
PB  - Elsevier
CY  - San Diego
ER  - 
TY  - JOUR
A1  - Lumaga, Maria Rosaria Barone
A1  - Cozzolino, Salvatore
A1  - Kocyan, Alexander
A1  - Menale, Bruno
A1  - Rudall, Paula J.
T1  - Exine micromorphology and ultrastructure in Neottieae (Epidendroideae, Orchidaceae)
JF  - Plant systematics and evolution
N2  - The diverse epidendroid orchid tribe Neottieae is characterized by multiple transitions between autotrophy and mycoheterotrophy, allogamous and autogamous mating systems, pollen released as tetrads or monads, and pollen exine tectate or semitectate. We use transmission and scanning electron microscopy on pollen of ten species of Neottieae to investigate whether the differences in pollen aggregation and exine micromorphology and ultrastructure reflect phylogenetic relationships, or whether this variation is subject to ecological constraints. Our results showed that differences in exine micromorphology are mostly concordant with phylogenetic relationships in Neottieae, i.e. an ascending tendency of pollen ornamentation from tectate (Cephalanthera) to semitectate (e.g. Neottia). In contrast, pollen aggregation, when plotted on the most recent phylogeny, shows repeated transitions between monads and tetrads that could be related to ecological constraints. Tetrads are present in species that are nectar rewarding, whereas monads are common in deceptive species. Cephalanthera is characterized by recalcitrant pollen, including the frequent occurrence of collapsed pollen. In this genus, the observed shifts from allogamous to autogamous or cleistogamous mating systems could help to reduce pollen damage caused by exposure to dry habitats.
KW  - Mating system
KW  - Monads
KW  - Neottieae
KW  - Pollenkitt
KW  - Tetrads
KW  - Ulcerate pollen
Y1  - 2014
U6  - https://doi.org/10.1007/s00606-013-0899-2
SN  - 0378-2697
SN  - 1615-6110
VL  - 300
IS  - 3
SP  - 505
EP  - 515
PB  - Springer
CY  - Wien
ER  -