CHROMOSOME-NUMBERS IN THE ARTHROPODIUM-DICHOPOGON COMPLEX (ASPARAGALES, ANTHERICACEAE)

The genera Arthropodium and Dichopogon (Asparagales: Anthericaceae) are considered to be closely related, if at all distinct. Limited evidence from previous cytological studies suggested a polyploid series within the complex where Arthropodium taxa have 2n = 22 chromosomes, intermediate species, 2n = 44, and Dichopogon taxa, 2n = 66. Examination of chromosomes in two thirds of the species in the Arthropodium-Dichopogon complex did not support that suggestion, as most of the species in both genera have a chromosome complement of 2n = 22. Evidence of polyploidy was found in D. strictus (2n = 22, 66), A. curvipes and D. preissii (2n = 44). The chromosomes are too small to provide useful information on chromosome morphology and C-band patterns. The lack of morphological features to delimit the two genera unequivocally, combined with the prevailing 2n = 22 karyotype across both, supports merging them under the name Arthropodium.