Geoffrey A. Levin

Flora of North America North of Mexico

The Flora of North America north of Mexico treats all native and naturalized vascular plants and bryophytes in Canada, Greenland, St. Pierre et Miquelon, and the continental United States including the Florida Keys and Aleutian Islands (approximately 18 million square kilometers). It provides accepted names, literature citations, basionyms, synonyms, morphological descriptions, habitat, geographical distribution, conservation or weed status, and a discussion of taxonomic issues for approximately 20,000 species. Of the total 30 volumes anticipated, 18 have been published and one is in press, treating 2021 genera and 12,393 species. For the remaining volumes, 763 genera and 5,008 species have been submitted, and 82 of the 144 families have been submitted in full. Completion is anticipated by the end of 2017. The project is managed by the Flora of North America Association. Content from published volumes is available through eFloras and JSTOR and has been provided to the World Flora informatics team.

Relationships Within the Spiny-Fruited Umbellifers (Scandiceae subtribes Daucinae and Torilidinae) as Assessed by Phylogenetic Analysis of Morphological Characters

Abstract Previous molecular systematic studies have indicated that the spiny-fruited umbellifers (Apiaceae tribe Caucalideae sensu Heywood) comprise two major lineages, recently delimited as Scandiceae subtribes Daucinae and Torilidinae, with the former including representation of tribe Laserpitieae sensu Drude. These taxa are allied with the monophyletic Scandiceae subtribe Scandicinae whose members lack spiny fruits. The relationship among these three subtribes is equivocal when nuclear ribosomal DNA internal transcribed spacer sequences are compared. Evidence from plastid DNA, however, suggests that Daucinae and Torilidinae are sister taxa. Herein, we provide results of a phylogenetic study of these spiny-fruited umbellifers based on morphology in order to study the evolution of these characters and to ascertain their utility for resolving relationships by comparison to the results of previous molecular analyses. Maximum parsimony analysis of 56 morphological characters resulted in a paraphyletic Torilidinae (Astrodaucus, Caucalis, Glochidotheca, Lisaea, Szovitsia, Torilis, Turgenia, and Yabea) from which a monophyletic Daucinae (Agrocharis, Ammodaucus, Cuminum, Daucus, Laserpitium, Orlaya, Pachyctenium, and Pseudorlaya) are derived. Scandicinae are maintained as monophyletic, sister to Daucinae plus Torilidinae. The genus Artedia, previously attributable to either Daucinae or Torilidinae, shows affinity with the former. The Daucinae plus Torilidinae clade is supported by three fruit synapomorphies—the regular distribution of appendages on both primary and secondary ridges, the presence of primary ridges and hairs on the face of the commissure, and the presence of vittae under the lateral ridges—but each subtribe cannot be circumscribed unambiguously on the basis of morphological data. Characters of the primary appendages exhibit less homoplasy than those of the secondary fruit appendages and support many clades identified in the molecular analyses. Parsimony analysis of combined morphological and ITS data, however, reaffirms the monophyly of subtribe Torilidinae and provides greater resolution of relationships within each of the subtribes than do either of the separate analyses. Communicating Editor: Paul Wilson

Two New Species of Acalypha (Euphorbiaceae) from Tropical Africa, and a Review of Some Robyns Names for Cupricolous Plants from the Democratic Republic of the Congo

Abstract Two new African species of Acalypha (Euphorbiaceae subfamily Acalyphoideae) are described and illustrated. Acalypha guineensis from Guinea and Sierra Leone is most similar to A. manniana, from which it differs by its smaller size, shorter peduncles on the pistillate inflorescences, smaller pistillate bracts with shorter and fewer teeth that are broadly triangular rather than linear-triangular, and velutinous rather than setose ovaries. Acalypha cupricola, endemic to copper-rich soils in the southern Democratic Republic of the Congo, belongs to the same species group as A. clutioides, A. dikuluwensis, and A. fuscescens, but can be distinguished from all three by its greater stature and more densely pubescent leaves. This name previously was a nomen nudum, and we also review other invalid names published by Robyns with A. cupricola.

Acalypha herzogiana (Euphorbiaceae), the correct name for an intriguing and commonly cultivated species

The genus Acalypha (Euphorbiaceae) contains three commonly cultivated ornamental species. Two of these have been propagated for centuries and are not known in the wild: Acalypha hispida and A. wilkesiana. A third species has only recently appeared in the horticultural trade, with the earliest evidence of its cultivation from the mid-1980s. This taxon is often grown in hanging baskets or as groundcover and owes its appeal to the possession of attractive, terminal pistillate inflorescences. Although it is commonly misidentified as A. hispaniolae, A. pendula, A. reptans, or A. repens, we present evidence that it is instead A. herzogiana, a native of Argentina, Bolivia, and Paraguay. Careful examination of the cultivated plants reveals that they differ from plants in the wild by possessing dimorphic pistillate inflorescences, a feature otherwise unknown in Acalypha. One of these inflorescence types is relatively inconspicuous and presents the typical structure of the majority of Acalypha in that the pistillate flowers are closely enveloped by an accrescent, foliaceous bract and not densely clustered. By contrast, the other inflorescence type is showy and highly anomalous. It consists of hundreds of densely clustered, ebracteate, abortive pistillate flowers. These unusual pistillate flowers are born in glomerules like the staminate flower and have no ovaries, but instead produce five to eight styles that arise directly from the receptacle in the position normally occupied by stamens in staminate flowers. We conclude that these unusual flowers are homologous to the staminate flowers of the wild plants and are the result of a homeotic mutation. Furthermore, we consider it unlikely that the homeotic mutation resulting in the development of the anomalous, showy pistillate inflorescences occurred in cultivation because without such inflorescences the plants would be non-descript and of little horticultural interest. The plant is a worthy subject for future research on hometic mutations, floral development, and gene expression.

A multivariate analysis of Pseudocymopterus (Apiaceae)1

Abstract Currently, Pseudocymopterus comprises two species, P. montanus and P. longiradiatus. Pseudocymopterus montanus is highly variable morphologically and in the past was subdivided into several poorly defined taxa. Multivariate analyses of 235 specimens reflecting the morphological variability exhibited by these plants and representing populations from throughout the ranges of both species were conducted to examine morphological discontinuities in Pseudocymopterus. Multivariate analysis of variance and principal component analysis confirmed that most of the characters previously used to recognize taxa within the complex are highly variable and overlapping among putative taxa. While no clearly distinguished clusters were revealed on the plots of the first three principal components, groups corresponding to P. montanus and P. longiradiatus were weakly separated from each other. Discriminant analysis using the same set of specimens showed that P. montanus and P. longiradiatus can generally be distinguished using a set of characters. These results are consistent with recent molecular analyses that revealed DNA sequence differences between these taxa. We therefore propose that Pseudocymopterus continues to be treated as having two species, P. longiradiatus and P. montanus, with no infraspecific taxa.

A multivariate analysis of Pteryxia terebinthina (Apiaceae)1

Abstract Recognition of infraspecific taxa in Pteryxia terebinthina (vars. albiflora, californica, foeniculacea, and terebinthina) is controversial. Multivariate analysis of variance, principal component analysis, and discriminant analysis of 265 specimens representing the morphological variability and geographic distribution of the species complex were conducted to test the validity of these infraspecific taxa. Results show that var. terebinthina can be recognized by its unique fruit wing structure. There are statistically significant differences among the remaining varieties for most of the characters previously used to recognize these varieties, but all of these characters are overlapping among the taxa. No clearly separated clusters are revealed in the principal component analysis and discriminant analysis does not allow reliable recognition of the varieties. We therefore propose that this species complex be recognized as containing two varieties, foeniculacea and terebinthina.

Four new species of Acalypha (Euphorbiaceae) fromMalesia

Four new species of Acalypha from the Malesian region, A. argentii, A. balgooyii, A. floresensis and A. pulogensis are described and illustrated.

A multivariate analysis of Cymopterus glomeratus, formerly known as C. acaulis (Apiaceae)

Abstract Five infraspecific taxa have been recognized in Cymopterus glomeratus (= C. acaulis): vars. glomeratus (= acaulis), fendleri, greeleyorum, higginsii, and parvus. The results of previous phylogenetic analyses of DNA sequence and morphological data have supported the close association of these five varieties, although the relationships among them could not be discerned. The recognition of infraspecific taxa within C. glomeratus is controversial. Multivariate analysis of variance and principal component analysis of 288 specimens representing the morphological variability and geographic distribution of this species complex were conducted to test the validity of these infraspecific taxa. Results show that most of the characters previously used to recognize these varieties are highly variable within the taxa. Although analysis of variance demonstrated some statistical differences among the varieties, patterns were not consistent. No clearly separated clusters are revealed in the principal component analysis and all five varieties were intermixed on the plots of the principal components. On the basis of the results of both phylogenetic and multivariate analyses, we propose that plants in this species complex be recognized as one species, C. glomeratus, with no varieties. The nomenclature and typification of this species are presented.

Systematics of Paradrypetes (Euphorbiaceae)

ABsTsRicr. Paradrypetes, a small genus known only from Brazil, has been placed near Drypetes in subfam. Phyllanthoideae, in subfam. Oldfieldioideae, and even excluded from the Euphorbiaceae altogether. In light of recent studies of the Oldfieldioideae, the morphology of Paradrypetes, particularly of its leaves and pollen, suggests that this genus is a primitive member of that subfamily. Its closest relative appears to be Podocalyx, in the tribe Podocalyceae, but numerous differences between these genera justify placing Paradrypetes in its own subtribe, the Paradrypetinae, G. Levin newly described herein. Two species of Paradrypetes are recognized, including a new species, Paradrypetes subintegrifolia. Paradrypetes Kuhlmann is a small Brazilian genus of Euphorbiaceae that has long been regarded as of uncertain relationships. When Kuhlmann (1935) described P. ilicifolia, heretofore the sole known species, he placed the genus in the subfam. Phyllanthoideae Webster because of its biovulate locules. He noted that the genus differed strikingly in its opposite leaves and epipetiolar inflorescences from all other members of the subfamily known to him. Despite these differences he suggested that it was related to Drypetes M. Vahl, which he stated was generally similar morphologically and specifically shares drupaceous fruits. The accompanying anatomical study by Milanez (1935) was interpreted to reinforced these conclusions but added further differences between the genera, particularly the presence of raphides, a crystal type otherwise absent in the Euphorbiaceae, throughout the primary tissues of Paradrypetes.

A synopsis of the New World species of Drypetes section Drypetes (Putranjivaceae) with asymmetrical fruits, including description of a new species

Abstract A synopsis of the New World species of Drypetes (Putranjivaceae) with asymmetrical drupes is presented. The group consists of three species: Drypetes alba, with two varieties,from the West Indies, Drypetes gentryi from Mexico, and the newly described Drypetes asymmetricarpafrom Costa Rica. The new species can be distinguished from both its relatives by its longer fruiting pedicels. In addition, the new species differs from Drypetes alba by its larger fruits, and from Drypetes gentryi by having shorter staminate pedicels and stigmas borne on styles (rather than sessile). Lectotypes are designated for Drypetes albavar. latifoliaand Drypetes incurva.