To evaluate the monophyly of subtribe Pleurothallidinae (Epidendreae: Orchidaceae) and the component genera and to reveal evolutionary relationships and trends, we sequenced the nuclear ribosomal DNA internal transcribed spacers (ITS1 and ITS2) and 5.8S gene for 185 taxa. In addition, to improve the overall assessments along the spine of the topology, we added plastid sequences from matK, the trnL intron, and the trnL-F intergenic spacer for a representative subset of those taxa in the ITS study. All results were highly congruent, and so we then combined the sequence data from all three data sets in a separate analysis of 58 representative taxa. There is strong support in most analyses for the monophyly of Pleurothallidinae and in some for inclusion of Dilomilis and Neocognauxia of Laeliinae. Although most genera in the nine clades identified in the analyses are monophyletic, all data sets are highly congruent in revealing the polyphyly of Pleurothallis and its constitutent subgenera as presently understood. The high degree of homoplasy in morphological characters, especially floral characters, limits their usefulness in phylogenetic reconstruction of the subtribe. Subtribe Pleurothallidinae (Epidendreae: Orchidaceae) comprise an estimated 4000 Neotropical species in ;30 genera (Luer, 1986a), accounting for 15‐20% of the species in the entire family. The vast majority are dipteran-, deceit-pollinated epiphytes with sympodial growth, unifoliate nonpseudobulbous stems or ‘‘ramicauls,’’ conduplicate leaves, velamentous roots, and an articulation between the pedicel and ovary. Genera have been circumscribed on the basis of number of pollinia—eight, six, four, or two—although there can be either eight or six in Brachionidium Lindl. (Luer, 1986a) and two or four (one large pair and one small pair) in Myoxanthus Poepp. & Endl. and Lepanthes Sw. (Stenzel, in press). Other floral characters used to distinguish genera include number of stigma lobes, sepal connation, resupination, and similarity of perianth parts (Luer, 1986a). Luer (1986a, 1987, 2000b) also placed great weight on the evolution of lip mobility and segregated species having any one of the various mechanisms in which this trait has independently evolved. This feature presumably

Phylogenetic relationships in Pleurothallidinae (Orchidaceae): combined evidence from nuclear and plastid DNA sequences

/pdf/north-america-floras-manuals-checklist-a-bibliography-5d763hxs6y.pdf

North America Floras, Manuals, & Checklist: A Bibliography

Subtribe Pleurothallidinae with just over 5000 species is possibly the most species-rich of all orchids. It has been growing steadily for more than two centuries, but the last three decades have been especially active in terms of systematic and phylogenetic studies in the group. The growth in species numbers has been accompanied by the marked increase in generic and infrageneric concepts. Nevertheless, Pleurothallidinae are plagued with cases of convergent and divergent morphology, and phylogenetic relatedness is not always apparent. This opens the door to controversial changes in generic circumscriptions that are considered too inclusive by some and too exclusive by others. A grave consequence of these disagreements is the difficulty of assessing which and how many species actually belong to each genus. Here an attempt is made to place generic names among their close relatives as a first step to re-evaluating the whole subtribe.

/pdf/genera-pleurothallidinarum-an-updated-phylogenetic-overview-4cpqmje9ue.pdf

Genera Pleurothallidinarum: an updated phylogenetic overview of Pleurothallidinae

Listing of the mottled duck (Anas fulvigula maculosa) as a priority species in the Gulf Coast Joint Venture of the North American Waterfowl Management Plan, coupled with recent declines of rice (Oryza sativa) acreage, ledus to investigate the nesting ecology of this species on agricultural lands in southwest Louisiana. We examined nest-site selection at macro- and microhabitat levels, nest success, causes of nest failures, and habitat features influencing nest success. We found that female mottled ducks preferred to nest in permanent pastures with knolls (53% of nests) and idle fields (22% of nests). Vegetation height was greater at nests than at random points within the same macrohabitat patch. Successful nests were associated with greater numbers of plant species, located farther from water, and associated with higher vegetation density values than were unsuccessful nests. We determined that mammalian predators caused most nest failures (77% of 52 unsuccessful nests). Our results suggest that nest success of mottled ducks on agricultural lands in southwest Louisiana could be improved by 1) locating large permanent pastures and idle fields near rice fields and other available wetlands, 21 managing plant communities in these upland areas to favor dense stands of perennial bunch grasses, tall composites, dewberry (Rubus trivialis), and other native grasses and forbs, and 3) managing cattle-stocking rates and the duration and timing of grazing to promote tall, dense stands of these plant taxa during the nesting season (March-June).

Nest-site selection and success of mottled ducks on agricultural lands in southwest Louisiana

Floras, or documented lists of vascular plant species in a defined area, are widely used in biodiversity research and conservation, and represent a common type of publication in regional botanical and natural history journals. Although all floras present common types of information, there has not yet been a formal attempt to develop community standards for floristic data. As a consequence, published floras often lack basic data describing the study area, taxonomic sources, and criteria for inclusion of species. Here, we develop a grading scheme for floras and apply it to 145 articles in 5 leading journals (Castanea, Rhodora, Sida/Journal of the Botanical Research Institute of Texas, Journal of the Torrey Botanical Club, and Southeastern Naturalist) published from 2000 through 2009. We found that the average ‘grade’ was 80%, and did not vary among journals. We also list common mistakes and confusions. We urge authors, editors, and reviewers to adopt (and adhere to) a set of standards that we provi...

https://bioone.org/journals/Castanea/volume-77/issue-1/11-035/Biodiversity-Data-in-the-Information-Age--Do-21st-Century/10.2179/11-035.pdf

Biodiversity Data in the Information Age: Do 21st Century Floras Make the Grade?

A phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)

A vascular flora survey of calcasieu parish, louisiana

Regular articleA phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)

A 335-bp segment of the NADH dehydroge nase F (ndhF) gene from a representative of each non flowering vascular plant division (Coniferophyta, Filico phyta, Ginkgophyta, Gnetophyta, Lycophyta, Psilophyta, Sphenophyta) has been sequenced and aligned with those of rice, tobacco, an orchid and a liverwort. Be cause ndhF is apparently absent in the genus Pinus L. (Coniferophyta), it has been speculated that this gene may be absent in the gymnosperms. However, this study suggests that the absence of the ndhF gene in Pinus may be unique and is not a general characteristic of the gym nosperms.

Ray Neyland

Papers

A phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)

A vascular flora survey of calcasieu parish, louisiana

Regular articleA phylogenetic analysis of subtribe Pleurothallidinae (Orchidaceae)

Rapid communication The ndhF chloroplast gene detected in all vascular plant divisions