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In a recently-published work it was demonstrated that the previous circumscription of Erechtites valerianifolius encompassed two distinct species, thus calling for the re-establishment of E. petiolatus. However, in that work it was overlooked that Senecio albiflorus, a replacement name for Cacalia prenanthoides, was published three months before E. petiolatus. In the present work we make the necessary amendments to the taxonomic treatment of this species of Erechtites due to this nomenclatural oversight. We also discuss the issue of the provenance of the type of C. prenanthoides.

The essential oil yield and composition of 17 species of the Asteraceae family were evaluated. Samples were obtained by hydrodistillation of the leaves and inflorescences and they were analyzed by GC-MS and GC-FID. A total of 13 species presented essential oils with yields ranging from 0.06 to 3.36% in fresh samples and from 0.07 to 2.53% in dried samples. Erechtites valerianifolius (Wolf) DC. produced the highest essential oil yield from both fresh and dried samples. Seventy-nine constituents were identified in essential oils from Asteraceae species, mainly consisting of monoterpenes and sesquiterpenes.

Structural features of cypsela are important to certain tribes of Asteraceae; thus, the ontogeny of the fruit (only the pericarp) of 10 weedy Asteraceae species was determined concerning the contribution to increase the knowledge of the fruit development in Asteraceae. The species analyzed are Conyza bonariensis L. (Cronquist.), Cosmos sulphureus Cav., Eclipta alba L. Hassk., Elephantopus mollis Kunth., Emilia sonchifolia L. DC., Galinsoga quadriradiata Ruiz & Pav., Erechtites valerianifolius (Wolf) DC., Parthenium hysterophorus L., Praxelis clematidea (Griseb) R.M. King & H. Rob and Sigesbeckia orientalis L. The mesocarp in the cypsela structure shows variation in the number of layers, the cell layer arrangement of the sclerenchyma and parenchyma, and the presence of phytomelanin that is especially striking. The mesocarp traits of Heliantheae alliance species are homogeneous, and it has been suggested that the derived character phytomelanin may not have the same evolutionary history in species ...

Mosquito-borne infections are a constant problem in Vietnam, and mosquito vector control is a primary approach to control these infections. Essential oils represent environmentally friendly alternatives to synthetic pesticides for mosquito control. The essential oils of two weedy species in Vietnam, Erechtites hieraciifolius and E. valerianifolius, have been obtained by hydrodistillation and analyzed by gas chromatography&ndash, mass spectrometry. The essential oils have been screened for mosquito larvicidal activity against Aedes albopictus, Ae. aegypti, and Culex quinquefasciatus. The essential oil from the aerial parts of E. hieraciifolius was rich in &alpha, pinene (14.5%), limonene (21.4%), and caryophyllene oxide (15.1%), while E. valerianifolius essential oil was dominated by myrcene (47.8%) and &alpha, pinene (30.2%). Both essential oils showed good larvicidal activity against Ae. albopictus (24-h LC50 10.5 and 5.8 &mu, g/mL, respectively) and Ae. aegypti (24-h LC50 10.6 and 12.5 &mu, g/mL, respectively). The essential oil of E. valerianifolius also showed good activity against Cx. quinquefasciatus larvae (24-h LC50 = 40.7 &mu, g/mL). Thus, Erechtites essential oils may serve as low-cost vector control agents for mosquito-borne infections.

Erechtites valerianifolius DC. (1838: 295). Distribution: a native of troical America, invasive in other tropical regions. = Senecio boninsimae Yatabe (1893: 1–3) Lectotype (designated here)—Bot. Mag. (Tokyo) vol. 7, plate II. 1893. No specimens were cited in the protologue of Senecio boninsimae, but one detailed drawing (plate II) was provided. Kitamura (1934) recorded this name as a synonym for Erechtites valerianifolius DC., citing “Bonin (S. Nishimura)”. The specimens collected by S. Nishimura were found at TI, but specimens collected before 1893 have not been found in any herbaria. Because we have not found adequate specimens that could serve as the type of this taxon in any herbaria, “plate II” should be regarded as the lectotype (ICBN Art. 9.2.)., Published as part of Watanabe-Toma, Kana, Ohi-Toma, Tetsuo & Murata, Jin, 2011, Typification of Angiospermae described from the Bonin Islands 1: Metachlamydeae, pp. 51-58 in Phytotaxa 33 on page 56, DOI: 10.11646/phytotaxa.33.1.4, http://zenodo.org/record/4894593, {"references":["Yatabe, R. (1893) New or little known plants of Japan. Botanical Magazine (Tokyo) 7: 1 - 3.","Kitamura, S. (1934) Compositae novae Japonicae VII. Acta Phytotaxonomica et Geobotanica 3: 97 - 111."]}