Nuclear DNA 2C-values for 16 species from Timor-Leste increases taxonomical representation in tropical ferns and lycophytes

Abstract

Knowledge regarding genome size allows us to infer relationships between taxa, address questions related to systematics and contribute to biodiversity studies. However, currently, less than 3% of described Pteridophyta species have genome size estimates reported in databases, and only around one third of these are tropical species, although the tropics are home of 86% of their diversity. The region of Timor-Leste, included in one of the 25 hotspots of biodiversity, is considered one of the richest areas of the world in terms of pteridophyte species. Nonetheless, research focused on this territory’s biodiversity and phylogenetic resources is lacking. This study presents novel 2C-values for 15 species of ferns collected in Timor-Leste, using the flow cytometry analysis. Furthermore, one species of lycophyte, Palhinhaea cernua (L.) Vasc. & Franco, was also studied and the 2C value estimated compared with a previous report. Estimates ranged from 10.45 pg in Selliguea feei Bory to 29.7 pg in Microsorum punctatum (L.) Copel. Using Leitch’s classification, all taxa analyzed are considered to have medium-size genomes. The data was compared with previous reports for similar species. These are the first 2C-values for two families and 7 genera of ferns, increasing the number of pteridophytes with reported C-values from 292 to 307.

Keywords

• genome size
• chromosome
• cytogenetics
• DNA amount
• nuclear DNA content
• Malesia