Parsimony and Bayesian analyses of plastid rbcL and trnL-F DNA sequence data of the pantropical family Euphorbiaceae sensu stricto (s.s.) are presented. Sampling includes representatives of all three subfamilies (Acalyphoideae, Crotonoideae, and Euphorbioideae), 35 of 37 tribes and 179 of the 247 genera of uniovulate Euphorbiaceae sensu lato (s.l.). Euphorbiaceae s.s. were recovered as a monophyletic group with no new adjustments in circumscription. Two clades containing taxa previously placed in Acalyphoideae are found to be successive sisters to all other Euphorbiaceae s.s. and are proposed here at subfamilial rank as Peroideae and Cheilosoideae. The remainder of the family fall into seven major lineages including Erismantheae and Acalyphoideae s.s. (parts of Acalyphoideae), Adenoclineae s.l., Gelonieae, articulated crotonoids and inaperturate crotonoids (parts of Crotonoideae), and Euphorbioideae. Potential synapomorphies and biogeographical trends are suggested for these clades. Acalyphoideae s.s., inaperturate crotonoids, and Euphorbioideae tribe Hippomaneae each have two major subclades that represent novel groupings without apparent morphological synapomorphies. Two subfamilies, 14 tribes, and 10 genera were found to be para- or polyphyletic. Noteworthy among these, Omphaleae are embedded in Adenoclineae, Hureae 1 Pachystromateae in Hippomaneae, Ditta in Tetrorchidium, and Sapium s.s. in Stillingia.

Molecular phylogenetic analysis of uniovulate Euphorbiaceae (Euphorbiaceae sensu stricto) using plastid RBCL and TRNL-F DNA sequences

The continued investigation of the middle Miocene palynoflora from the Lavanttal Basin reveals numerous additional angiosperm taxa. The Myrtales to Ericales pollen record documented here comprises 46 different taxa belonging to Onagraceae (Ludwigia), Ericaceae (Craigia, Reevesia, Tilia), Anacardiaceae (Pistacia), Rutaceae (Zanthoxylum), Sapindaceae (Acer), Santalaceae (Arceuthobium), Amaranthaceae, Caryophyllaceae, Polygonaceae (Persicaria, Rumex), Cornaceae (Alangium, Cornus, Nyssa), Ebenaceae (Diospyros), Ericaceae (Andromeda, Arbutus, Empetrum, Erica), Sapotaceae (Pouteria, Sideroxylon), Styracaceae (Rehderodendron) and Symplocaceae (Symplocos). Koppen signatures of potential modern analogues of the additional fossil woody elements confirm the hypothesis of a subtropical (Cfa, Cwa) climate at lower elevations and subsequent transition into a temperate climate with altitudinal succession (Cfa → Cfb/Dfa → Dfb; Cwa → Cwb → Dwb-climate). The fossil plants represent different vegetation units, from wetland lowlands to well-drained montane forests. Many of the fossil taxa have potential modern analogues that can be classified as nemoral and/or meridio-nemoral and/or semihumid-meridional vegetation elements. New is the recognition of oreotropical elements, which are direct indicators for a substantial altitudinal gradient.

https://www.tandfonline.com/doi/pdf/10.1080/00173134.2015.1096566

Combined LM and SEM study of the middle Miocene (Sarmatian) palynoflora from the Lavanttal Basin, Austria: part IV. Magnoliophyta 2 – Fagales to Rosales

Ovule and seed structure in Euphorbioideae, one of the five euphorbiaceous subfamilies, is surveyed to evaluate its systematic implications on the basis of 79 species representing four of five tribes. All Euphorbioideae, like two other "uniovulate" subfamilies Acalyphoideae and Crotonoideae, but unlike most of two "biovulate" subfamilies Oldfieldioideae and Phyllanthoideae, consistently have a persistent and palisadal exotegmen composed of radially elongate, sclerotic, and pitted cells. Within Euphorbioideae, the tribe Stomatocalyceae (also with the palisadal exotegmen) is unusual in having vascular bundles in outer integument and clearly distinct from the remaining Euphorbioideae and the other "uniovulate" subfamilies. With the exclusion of Stomatocalyceae, Euphorbioideae are not anatomically divided into major groups such as a pseudanthial and a non-pseudanthial clade, but instead have some remarkable diversity within a tribe, a subtribe, and even a genus in the three ovule and seed characters: (1) the thickness of the inner integument, (2) the thickness of the outer integument, and (3) the presence or absence of an aril. Groups of genera and species wrapped by different combinations of their characteristics, however, are not necessarily harmonized with tribal or subtribal classifications available. Anatomical similarities and dissimilarities presented in this paper, as well as relationships among taxa presented in the classifications available, will be critically evaluated in the light of results of ongoing molecular phylogenetic analyses.

Ovules and seeds in Euphorbioideae (Euphorbiaceae): structure and systematic implications.

Pollen morphology, exine structure and systematics of Acalyphoideae (Euphorbiaceae), Part 4

The middle Miocene palynoflora and palaeoenvironments of Eskihisar (Yatağan basin, south‐western Anatolia): a combined LM and SEM investigation

Pollen morphology, exine structure, and systematics of Acalyphoideae (Euphorbiaceae), part 3. Tribes Epiprineae (Epiprinus, Symphyllia, Adenochlaena, Cleidiocarpon, Koilodepas, Cladogynos, Cephalocrotonopsis, Cephalocroton, Cephalomappa), Adelieae (Adelia, Crotonogynopsis, Enriquebeltrania, Lasiocroton, Leucocroton), Alchorneae (Orfilea, Alchornea, Coelebogyne, Aparisthmium, Bocquillonia, Conceveiba, Gavarretia), Acalypheae pro parte (Ricinus, Adriana, Mercurialis, Leidesia, Dysopsis, Wetria, Cleidion, Sampantaea, Macaranga).

Stanley Yankowski

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