To evaluate the evolutionary relationships among species of Peperomia subg. Micropiper, a phylogenetic analysis based on the DNA sequences of plastid regions atpB-rbcL, psbK-I, rpL16, rpS16, trnG, trnK (including matK), trnL-L-F, and trnS-G was conducted using 20 species, in addition to four outgroup species. The trnK sequences of 46 species and trnL-L-F sequence of one species were quoted from GenBank and also included in the analysis. The results showed that P. subg. Micropiper includes seven major clades, which are also supported by morphological characteristics. They are recognized as sectionequivalent plant groups, namely Alatoid, Blandoid, Glabelloid, Glaucoid, Japonicoid, Lanceolatoid, and Rotundifolioid. A chromosome analysis of the subgenus yielded nine new counts: 2n = 22 (diploid) for P. alata, P. bicolor, P. diaphanoides, P. flexicaulis, P. hylophila, P. polystachya and P. prosterata, 2n = 44(tetraploid) for P. okinawensis and 2n = 132 (dodecaploid) for P. reticulata. Japonicoid, which occurs outside the Americas, i.e. in Asia, Africa, and the Pacific islands, is tetraploid, decaploid, and dodecaploid (not diploid), while the remaining six plant groups are native to the Americas and diploid (except Glaucoid, which is tetraploid). Further, P. diaphanoides is conspecific with P. glabella. Peperomia boninsimensis from the Ogasawara Islands, Japan, is more closely related to Polynesian species than to other Japanese species. Peperomia okinawensis should be regarded as a variety of P. japonica.
Acystopteris taiwaniana, formerly known only from Taiwan, is newly recorded in Japan (northern and central Honshu and Shikoku). Chromosome counts and DNA sequences (plastid rbcL and nuclear PgiC) suggested that it is an allotetraploid species originating from hybridization between diploid A. japonica and an unknown diploid species. Acystopteris taiwaniana differs from A. japonica in having glandular hairs on the indusia of the sori, paler stipes and rachises, wider angles of divergence of pinnae from the rachis and larger spores, although there overlaps in the variation. Triploid sterile hybrids between the two species occur occasionally at the periphery of populations of one of the parental species in Japan.
Three new species of Hydrobryum (Podostemaceae) from central Laos are described. These species, like most other congeners, share crustose roots, but differ in the characteristics of the bract, spathella, stamen, and/or ovary locule. Their recognition as distinct was supported by molecular phylogenetic analyses. As a result, 16 species of Hydrobryum occur in Laos and 33 species occur throughout southeastern and eastern Asia.
Sciaphila yakushimensis var. okinawensis from Okinawa and Ishigaki Islands, Japan, is described as new. It can be distinguished from S. yakushimensis var. yakushimensis by the morphology of the staminate and carpellate flowers.
A new variety, Goodyera schlechtendaliana Rchb. f. var. yakushimensis Suetsugu & Hiros. Hayak. (Orchidaceae), from Yakushima and Okinawa, is described. It is distinguished from G. schlechtendaliana var. schlechtendaliana by a combination of morphological characters, such as straighter lateral sepals, straighter lip, sparsely hairy inside the concave-saccate hypochile, and slender leaves.
Ixora yunnanensis (Rubiaceae) is recorded for the first time in India. Previously, it was considered endemic to Yunnan Province, China. The present report extends its distribution range ca. 760 km westward. A brief description of the plant along with photographs and a distribution map are provided to facilitate its unambiguous identification in the future.