Evolution of Philodendron (Araceae) species along Neotropical biomes

Abstract

Philodendron is the second most diverse genus of the Araceae, a tropical monocot family with significant morphological diversity along its wide geographic distribution in the Neotropics. Although evolutionary studies of Philodendron were conducted in recent years, the phylogenetic relationship among its species remains unclear. Additionally, analyses conducted to date suggested the inclusion of all American representatives of a closely related genus, Homalomena, within the Philodendron clade. A thorough evaluation of the phylogeny and timescale of these lineages is thus necessary to elucidate the tempo and mode of evolution of this large Neotropical genus and to unveil the biogeographic history of Philodendron evolution along the Amazonian and Atlantic Rain Forests, as well as open dry forests of South America. To this end, we have estimated the molecular phylogeny for 68 Philodendron species, which consists of the largest sampling assembled to date aiming the study of the evolutionary affinities. We have also performed ancestral reconstruction of species distribution along biomes. Finally, we contrasted these results with the inferred timescale of Philodendron and Homalomena lineage diversification. Our estimates indicate that American Homalomena is the sister clade to Philodendron. The early diversification of Philodendron took place in the Amazon Forest from Early to Middle Miocene, followed by colonization of the Atlantic Forest and the savanna-like landscapes, respectively. Based on the age of the last common ancestor of Philodendron, the species of this genus diversified by rapid radiations, leading to its wide extant distribution in the Neotropical region.

Monocot plastid phylogenomics, timeline, net rates of species diversification, the power of multi‐gene analyses, and a functional model for the origin of monocots

“…The high rates of diversification in Araceae sister to Lemnoideae may thus reflect limited dispersal of fleshy fruits in tropical forest understories, as well as the topographic dissection of mountainous terrain occupied by epiphytic and hemiepiphytic taxa. High speciation rates in Araceae have not previously been reported, but the stem ages estimated for several large genera by Nauheimer et al (2012) and for Philodendron by Loss-Oliveira et al (2016) are consistent with this hypothesis. Our estimates of the stem ages for several large genera-31 Mya for Anthurium (950 species), 29 Mya for Philodendron (482 species), 9.7 Mya for Rhaphidophora (105 species), and 3.1 Mya for Alocasia (78 species; all species counts from Boyce and Croat, 2018)-suggest that a more detailed analysis of Araceae might uncover several extraordinarily rapid diversifications nested within the higher aroids.…”

Contrasting evolutionary histories in Neotropical birds: Divergence across an environmental barrier in South America

“…The northern Atlantic Forest and eastern Amazonia were connected both across the northern Cerrado and its transition with the Caatinga region and along the coastal region in northeastern Brazil. These historical contacts are supported by palaeoclimatic and geological data (Cheng et al, ; Ledo & Colli, ; Lundberg et al, ), as well as several evolutionary studies of diverse plant (Loss‐Oliveira, Sakuragui, Soares, & Schrago, ; Melo Santos, Cavalcanti, Silva, & Tabarelli, ) and animal taxa (Batalha‐Filho, Fjeldså, Fabre, & Miyaki, ; Costa, ; Prates et al, ; Trujillo‐Arias et al, ).…”