BIODIVERSITAS ISSN: 1412-033X Volume 23, Number 8, August 2022 E-ISSN: 2085-4722 Pages: 4097-4108 DOI: 10.13057/biodiv/d230830 Morpho-anatomical characterization and DNA barcode of Cosmos caudatus Kunth. HERY PURNOBASUKI 1,2, , GALUH AYU RAKHASHIWI 1 , JUNAIRIAH 1 , DWI KUSUMA WAHYUNI 1,2 , RAMADHANI EKA PUTRA 3 , RIKA RAFFIUDIN 4 , RC HIDAYAT SOESSILOHADI 5 1 Department of Biology, Faculty of Science and Technology, Universitas Airlangga. Jl. Dr. Ir. H. Soekarno, Surabaya 60115, East Java, Indonesia. Tel.: +62-31-5936501, Fax.: +62-31-5936502.  email: hery-p@fst.unair.ac.id 2 Biotechnology of Tropical Medicinal Plants Research Group, Universitas Airlangga. Jl. Dr. Ir. H. Soekarno, Surabaya 60115, East Java, Indonesia 3 School of Life Sciences and Technology, Institut Teknologi Bandung. Jl. Ganeca No.10, Bandung 40132, West Java, Indonesia 4 Department of Biology, Faculty of Mathematic and Natural Sciences, Institut Pertanian Bogor. Jl. Meranti, Kampus IPB Darmaga, Bogor 16680, West Java, Indonesia 5 Faculty of Biology, Universitas Gadjah Mada. Jl. Teknika Selatan, Sleman 55281, Yogyakarta, Indonesia Manuscript received: 24 March 2022. Revision accepted: 26 July 2022. Abstract. Purnobasuki H, Rakhashiwi GA, Junairiah, Wahyuni DK, Putra RE, Raffiudin R, Soessilohadi RCH. 2022. Morpho- anatomical characterization and DNA barcode of Cosmos caudatus Kunth. Biodiversitas 23: 4097-4108. Secondary metabolites in plants have various benefits, therefore their distribution in plant body parts is important to study. The identification process of plants should be conducted using several characters, including morphological and molecular data. This study aimed to identify and confirm Cosmos caudatus Kunth using morpho-anatomy characters and DNA barcodes. The plants used were three samples taken from the Husada Graha Famili Park, Surabaya. The morpho-anatomical investigation was carried out descriptively, while the DNA barcoding study was processed by amplifying and sequencing the rbcL and matK genes. Morphological studies indicate that the roots and stems of C. caudatus are similar to the organs of dicots shrubs in general. The leaves have a pinnate type with two different colors on each side of the leaf. Compound flowers are cup-type with two types of flowers, namely disc flowers and ray flowers. Based on anatomical observation, all vegetative organs have the same tissue as dicotyledonous plants. The anatomical characteristic of C. caudatus lies in its trichomes due to its anthocyanin content and stomata which are anomocytic and anisocytic types. DNA barcoding results showed that the three sample plants had identical similarities with several Cosmos genera contained in the GenBank database with percentage identities values above 98%, query covers 96-100%, and e-values of 0. Keywords: Barcode, Cosmos caudatus, matK, genetic diversity, morpho-anatomy, rbcL Abbreviations: DNA: Deoxyribonucleic acid, matK: maturase-K, rbcL: ribulose-bisphosphate carboxylase large subunit, CBOL: Consortium for Barcode of Life, PCR: Polymerase chain reaction, BLAST: Basic Local Alignment Search Tool INTRODUCTION Cosmos caudatus Kunth has known locally as Kenikir, belongs to the family Asteraceae (Cheng et al. 2015; Yusoff et al. 2021). The family is distributed throughout Neotropics (POWO 2022) and often makes up the forest floor vegetation, including C. caudatus (Christenhusz and Byng 2016; Panero and Crozier 2016; Willis 2017). The species is herbal plant originating from Latin America and then spreading to Southeast Asia (Bodeker 2009; Moshawih et al. 2017). Cosmos caudatus has abundant benefits, including antibacterial (Yusoff et al. 2014; Safita et al. 2015), anti- inflammatory (Ajaykumar et al. 2012), antioxidant and anticancer (Cheng et al. 2015). Various health benefits of the species are due to the presence of secondary metabolites (Mediani et al. 2013). According to Moshawih et al. (2017), C. caudatus has various secondary metabolites, including flavonoids, saponins, terpenoids, tannins, and phenols. The presence of bioactive components can be found by analyzing plant extracts, especially on the leaves (Phong et al. 2022). Wahyuni et al. (2019) add that secondary metabolites can be found in specific areas of plant organs. To comprehend the location of cells that store the secondary metabolites, anatomical research is necessary (Ilham et al. 2022), since anatomical characteristics can also help identify plants. Therefore, its values are crucial for classifying plants. Rahman et al. (2013) reported anatomical features of 36 plant species from the Rajshahi division, Bangladesh, including C. caudatus. The species has stomata with anomocytic and anisocytic types. Classification and phylogenetic studies mainly depend on morphological cues (Kaur and Singh 2020). The weakness of morphological markers is in terms of variability, and it can cause serious taxonomic problems in species with a wide geographic range. Abiotic factors can substantially impact both micro and macromorphological features, even though ontogenetic programming contributes to morphological variability in some cases. As an example, Cosmos bipinnatus in Central Mexico exhibits intricate morphological variations due to environmental conditions, such as height and NH4 content surrounding the plant's habitat (Paniagua-Ibánez et al. 2015).