Refine
Document Type
- Article (4)
- Part of Periodical (1)
Language
- English (5)
Has Fulltext
- yes (5)
Is part of the Bibliography
- no (5)
Keywords
- Neotropics (4)
- taxonomy (3)
- Africa (1)
- Alchorneeae (1)
- Anatomy (1)
- Ankarana (1)
- Atlantic Forest (1)
- Croton section Cyclostigma (1)
- Croton section Julocroton (1)
- Crotoneae (1)
The formerly monotypic genus Paranecepsia Radcl.-Sm. is expanded with the description and illustration of a second species, Paranecepsia andrafiabensis Barberá & O.Lachenaud sp. nov. Molecular phylogenetic analyses of plastid rbcL and trnL-F data confirm a sister relationship between the new species and P. alchorneifolia Radcl.-Sm., as members of the alchorneoids clade. Paranecepsia andrafiabensis sp. nov. is notable for expanding the character states for the genus (now including both 2- and 3-locular ovary species) and broadening the geographic range of the genus from continental Africa to Madagascar. The new species adds to the diverse karst limestone endemics of northwestern Madagascar, where it has a very restricted distribution at the base of the western wall of the Ankarana tsingy. An amended generic description of Paranecepsia and a key to the species are also presented. Paranecepsia andrafiabensis sp. nov. is provisionally assessed as VU D1 based on the IUCN Red List criteria.
We describe Croton calcareus Riina & Mateo-Ram. sp. nov., a new species in Croton section Cyclostigma (dragon's blood trees) from the state of Chiapas (Mexico). This species is a small tree growing in dry forest on calcareous substrates. Both morphological and molecular data support C. calcareus sp. nov. as a new species closely related to C. redolens, another dry forest taxon from northern Venezuela. We provide illustrations, a distribution map and suggestions for species conservation status. The new species along with Croton draco are the only known representatives of C. section Cyclostigma occurring in Mexico.
We describe and illustrate three new species of Euphorbia subgenus Chamaesyce from Brazil: E. blepharadena O.L.M.Silva & Cordeiro sp. nov., E. longipedunculata O.L.M.Silva & Riina sp. nov. and E. sobolifera O.L.M.Silva & P.J.Braun sp. nov. Based on morphological characteristics, E. blepharadena sp. nov. and E. longipedunculata sp. nov. are placed in the subcosmopolitan section Anisophyllum, whereas E. sobolifera sp. nov. is placed in the more geographically restricted section Crossadenia. The three new species are compared with their most similar species in each section, and accompanied by comments on habitat and distribution, illustrations, photographs, and proposed conservation status.
We describe and illustrate Croton restingae Sodré & Riina sp. nov., a new species endemic to a restricted area in the state of Rio de Janeiro, Brazil, characterized by a particular type of vegetation of the Atlantic Forest known as restinga. The new species belongs to Croton sect. Adenophylli subsect. Laceratoglandulosus, which is supported by morphology and a phylogenetic analysis based on nrDNA ITS sequence data. Croton restingae is most closely related to C. echioides and C. laceratoglandulosus, also in subsect. Laceratoglandulosus, with which it shares the fruit columella with three non-inflated, flat or slightly ascending apical appendages. Croton restingae differs from them by its sessile or shortly stipitate leaf nectaries, revolute pistillate sepals, styles distally 2-fid and basally united forming a column, and larger capsules (7.5–8 × 8.5–9.3 mm). Croton restingaeʼs habitat, conservation status, phenology, morphology and phylogenetic relationships are discussed, and a map with its geographic distribution is also included.
Croton maranonensis: a new species of Euphorbiaceae from the tropical inter-Andean dry valleys
(2024)
We describe Croton maranonensis Riina & Martín-Muñoz sp. nov., a species in Croton section Julocroton (Mart.) G.L.Webster from the seasonally dry tropical forests and shrublands of the inter-Andean valleys. This species is a small shrub occurring along the Marañón river valley in Peru and similar dry areas in southern Ecuador. We surveyed morpho-anatomical characters of the new species and closely related taxa. To confirm the placement of the new species in C. section Julocroton, we conducted a molecular phylogenetic analysis including three accessions of the new species and selected representatives of section Julocroton and related groups within Croton L. Micro- and macro-morphological evidence, and molecular data support C. maranonensis sp. nov. as an independent lineage within the C. section Julocroton clade. We compared the new species with morphologically similar species in the same section that also occur in the Andean region, including C. flavispicatus Rusby, C. triqueter Lam., and C. hondensis (H.Karst.) G.L.Webster.