Abstract
The genus Ophiorrhiza Linnaeus (1751: 150) (Ophiorrhizeae, Rubioideae, Rubiaceae) comprises of ca. 318 taxa in tropical and tropical subtropical Asia, extending to Australia, New Guinea and the Pacific Islands (Darwin 1976, Chen & Taylor 2011, Bremer & Manen 2000), with its greatest diversity in southeastern Asia (Davis et al. 2009, Hareesh 2017, Hareesh & Sabu 2018). The genus has been revised taxonomically in some geographic regions such as Australia (Halford 1991), China (Lo 1990, Chen & Taylor 2011), India (Deb & Mondal 1997, Hooker 1880, Hareesh & Sabu 2018) and the Pacific (Darwin 1976). In the Flora of China, 73 species were reported, in which 47 species are endemic (Chen & Taylor 2011, Yang et al. 2018, Tu et al. 2018, Wu et al. 2017, 2018, Duan et al. 2019) and mainly occurring in southwestern region of China, commonly growing on humid slopes or along valleys under dense forest (Lo 1999, Yang et al. 2018). Generally, Ophiorrhiza species are annual to perennial suffrutescent herbs or small shrubs with cymose inflorescences. Fruit capsules are broadly obcordate, laterally flattened, papery, dry and usually dehiscent loculicidal (Lo 1990, Deb & Mondal 1997, Chen & Taylor 2011, Hareesh 2017, Wu et al. 2018). The Ophiorrhiza species (O. mungos L. (1753: 150), O. mungos L. var. angustifolia (Thwaites) Hook.f. (1880: 77), and O. rugosa Wall. (1824: 547) var. decumbens (Gardner ex Thwaites) Deb & Mondal (1983: 228)) are commercially important as source of Camptothecin (CPT), a potent anticancer drug as well as antiviral and antimicrobial properties (Rajan et al. 2016, Taher et al. 2020).
References
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<p>Blume, C.L. (1826) <em>Bijdragen tot de flora van NederlandschIndië </em>16<em>. </em>Lands Drukkerij, Batavia, pp. 943–1066. https://doi.org/10.5962/bhl.title.6656</p>
<p>Chen, T. & Taylor, C.M. (2011) <em>Ophiorrhiza</em>. <em>In</em>: Wu, Z.Y., Raven, P.H. & Hong, D.Y. (Eds.) <em>Flora of China</em> 19. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, pp. 258–282.</p>
<p>Darwin, S.P. (1976) The Pacific species of <em>Ophiorrhiza</em> L. (Rubiaceae). <em>Lyonia</em> 1 (2): 48–101.</p>
<p>Davis, A.P., Govaerts, R., Bridon, D.M., Ruhsam, M., Moat, J. & Brummitt, N.A. (2009) A global assessment of distribution, diversity, endemism, and taxonomic effort in the Rubiaceae. <em>Annals of the Missouri Botanical Garden</em> 96 (1): 68–78. https://doi.org/10.3417/2006205</p>
<p>Deb, D.B. & Mondal, D.C. (1997) Taxonomic revision of the genus <em>Ophiorrhiza</em> L. (Rubiaceae) in Indian subcontinent. <em>Bulletin of the Botanical Survey of India</em> 39: 1–148.</p>
<p>Deb, D.B. & Rout, R.C. (1989) Two new species of the genus <em>Spiradiclis </em>(Rubiaceae) from India. <em>Candollea</em> 44: 225–229.</p>
<p>Duan, L.D., Lin, Y. & Lu, Z. (2019) <em>Ophiorrhiza shiqianensis</em> (Rubiaceae), a new species from Guizhou, China. <em>PhytoKeys </em>121: 43–51. https://doi.org/10.3897/phytokeys.121.30570</p>
<p>Hareesh, V.S. (2017) <em>Ophiorrhiza jacobii</em> (Rubiaceae) sp. nov. from Western Ghats, India. <em>Nordic Journal of Botany</em> 36: e01519. https://doi.org/10.1111/njb.01519</p>
<p>Hareesh, V. S. & Sabu, M. (2018) The genus <em>Ophiorrhiza </em>(Rubiaceae) in Andaman and Nicobar Islands, India with a new species. <em>Phytotaxa</em> 383 (3): 259–272. https://doi.org/10.11646/phytotaxa.383.3.3</p>
<p>Hooker, J.D. (1880 “1882”) Order LXXV. Rubiaceae. <em>In</em>: Hooker, J.D. (Ed.) <em>Flora of British India</em> 3 (7). Reeve, London, pp. 17–192. https://doi.org/10.5962/bhl.title.678</p>
<p>Korthals, P.W. (1851) <em>Ophiorrhiza</em> L. <em>Nederlandsch kruidkundig archief</em> 2: 122–133.</p>
<p>Linnaeus, C. (1753) <em>Species Plantarum</em> 1. ImpensisLaurentiiSalvii, Holmiae, 560 pp.</p>
<p>Liu, J., Pan, B., Li, S.W. & Xu, W.B. (2017) <em>Spiradiclisquanzhouensis</em>(Rubiaceae): A new species from limestone area in Guangxi, China. <em>NordicJournal of Botany</em> 36 (3): njb-01595. https://doi.org/10.1111/njb.01595</p>
<p>Li, J.-L., Yuan, Q., Liu, Y., Song, X.-F., Pan, B., Qu, C.-H. & Wu, L. (2021) Two new species of <em>Spiradiclis</em> (Rubiaceae) from limestone areas in southwestern China. <em>Nordic Journal of Botany</em> 39 (2): e02979. https://doi.org/10.1111/njb.02979</p>
<p>Lo, H.S., Sha, W.L. & Chen, X.X. (1983) A revision of the genus <em>Spiradiclis </em>Bl. <em>Acta Botanica Austro Sinica</em> 1: 27–36. [In Chinese]</p>
<p>Lo, H.S. (1990) Taxonomic revision of the Chinese species of <em>Ophiorrhiza</em> (Rubiaceae).<em> Bulletin of Botanical Research</em>, Harbin 10 (2): 1–82.</p>
<p>Lo, H.S. (1999) <em>Ophiorrhiza</em>. <em>In</em>: Lo, H.S. (Ed.) <em>Flora ReipublicaePopularisSinicae</em> 71(1). Science Press, Beijing, pp. 110–74 [In Chinese]</p>
<p>Pan, B., Tu, R.-H., Hareesh, V.-S. & Wu, L. (2019) <em>Spiradiclis cavicola</em> (Rubiaceae), a New Species from Limestone Caves in Southwestern China. <em>Annales BotaniciFennici</em> 56 (1–3): 1–4. https://doi.org/10.5735/085.056.0101</p>
<p>Raizada, M.B. & Bennet, S.S.R. (1982) Five new combinations and a new name for Indian flowering plants. <em>Indian Forester</em> 108 (4): 302–303. [https://www.i-scholar.in/index.php/indianforester/article/view/10823]</p>
<p>Rajan, R., Varghese, S.C., Kurup, R., Gopalakrishnan, R., Venkataraman, R., Satheeshkumar, K. & Baby, S. (2016) HPTLC-based quantification of camptothecin in <em>Ophiorrhiza</em> species of the southern Western Ghats in India. <em>Cogent Chemistry</em> 2 (1): 1275408. https://doi.org/10.1080/23312009.2016.1275408</p>
<p>Razafimandimbison, S.G. & Rydin, C. (2019) Molecular-based assessments of tribal and generic limits and relationships in Rubiaceae (Gentianales): Polyphyly of Pomazoteae and paraphyly of Ophiorrhizeae and <em>Ophiorrhiza</em>.<em> Taxon </em>68 (1): 72–91. https://doi.org/10.1002/tax.12023</p>
<p>Robbrecht, E. (1988) Tropical woody Rubiaceae. <em>Opera BotanicaBelgica</em> 1: 599–602.</p>
<p>Taher, M., Shaari, S.S., Susanti, D., Arbain, D. & Zakaria, Z.A. (2020) Genus <em>Ophiorrhiza</em>: A review of its distribution, traditional uses, phytochemistry, biological activities and propagation. <em>Molecules</em> 25 (11): 2611. https://doi.org/10.3390/molecules25112611</p>
<p>Tu, R.H., Li, J.L. & Wu L. (2018) <em>Ophiorrhiza gaoligongensis</em> (Rubiaceae), a new species from Southwestern China. <em>Novon</em> 26 (4): 351–354. https://doi.org/10.3417/2018309</p>
<p>Wang, R.J. (2016) <em>Spiradiclis jingxiensis </em>sp. nov. (Rubiaceae) from Guangxi, China. <em>Nordic Journal of Botany</em> 34 (5): 550–552. https://doi.org/10.1111/njb.01134</p>
<p>Wen, Z.-J., Yang, J.-C., Xu, Y.-F. & Wu, L. (2019) <em>Spiradiclis densa</em> sp. nov. (Rubaceae) from limestone areas in Guangxi, China. <em>Nordic Journal of Botany</em> 37 (5): e02190. https://doi.org/10.1111/njb.02190</p>
<p>Wu, L., Tong, Y., Pan, B. & Liu, Q.R. (2016) <em>Spiradiclis glabra </em>sp. nov. (Rubiaceae) from limestone areas in Guangdong, China. <em>Nordic Journal of Botany</em> 34 (6): 718–721. https://doi. org/10.1111/njb.01156</p>
<p>Wu, L., Hareesh, V.S. & Yu, Y.L. (2017) The taxonomic identity of <em>Ophiorrhiza rarior</em> and <em>O. mycetiifolia</em> (Rubiaceae). <em>Phytotaxa </em>299 (2): 261–266. https://doi.org/10.11646/phytotaxa.299.2.10</p>
<p>Wu, L., Tan, Y. H., Hareesh, V.S. & Liu, Q.R. (2018) <em>Ophiorrhiza macrocarpa</em> (Rubiaceae), a new viviparous species from Yunnan, southwestern China. <em>Nordic Journal of Botany</em> 36: e01637. https://doi.org/10.1111/njb.01637</p>
<p>Wu, L., Li, X., Liu, W.-J. & Liu, Q.-R. (2019a) <em>Spiradiclis karstana</em> (Rubiaceae), a new species from Yunnan, China. <em>PhytoKeys</em> 117: 1–8. https://doi.org/10.3897/phytokeys.117.28281</p>
<p>Wu, L., Wang, B.-M., Pan, B. & Yu, X.-L (2019b) <em>Spiradiclis tubiflora </em>(Rubiaceae), a new cave-dwelling species from southern China. <em>In</em>: Cai, J., Yu, W.-B., Zhang, T., Li, D.-Z. (Eds.) Revealing of the plant diversity in China’s biodiversity hotspots. <em>PhytoKeys </em>130: 217–224. https://doi.org/10.3897/phytokeys.130.34625</p>
<p>Yang, C.-D., He, X.-Z. & Gou, G.-Q. (2018) <em>Ophiorrhiza guizhouensis</em> (Rubiaceae), a new species from Guizhou Province, southwestern China. <em>PhytoKeys </em>95: 121–126. https://doi.org/10.3897/phytokeys.95.22506</p>
<p>Blume, C.L. (1826) <em>Bijdragen tot de flora van NederlandschIndië </em>16<em>. </em>Lands Drukkerij, Batavia, pp. 943–1066. https://doi.org/10.5962/bhl.title.6656</p>
<p>Chen, T. & Taylor, C.M. (2011) <em>Ophiorrhiza</em>. <em>In</em>: Wu, Z.Y., Raven, P.H. & Hong, D.Y. (Eds.) <em>Flora of China</em> 19. Science Press, Beijing & Missouri Botanical Garden Press, St. Louis, pp. 258–282.</p>
<p>Darwin, S.P. (1976) The Pacific species of <em>Ophiorrhiza</em> L. (Rubiaceae). <em>Lyonia</em> 1 (2): 48–101.</p>
<p>Davis, A.P., Govaerts, R., Bridon, D.M., Ruhsam, M., Moat, J. & Brummitt, N.A. (2009) A global assessment of distribution, diversity, endemism, and taxonomic effort in the Rubiaceae. <em>Annals of the Missouri Botanical Garden</em> 96 (1): 68–78. https://doi.org/10.3417/2006205</p>
<p>Deb, D.B. & Mondal, D.C. (1997) Taxonomic revision of the genus <em>Ophiorrhiza</em> L. (Rubiaceae) in Indian subcontinent. <em>Bulletin of the Botanical Survey of India</em> 39: 1–148.</p>
<p>Deb, D.B. & Rout, R.C. (1989) Two new species of the genus <em>Spiradiclis </em>(Rubiaceae) from India. <em>Candollea</em> 44: 225–229.</p>
<p>Duan, L.D., Lin, Y. & Lu, Z. (2019) <em>Ophiorrhiza shiqianensis</em> (Rubiaceae), a new species from Guizhou, China. <em>PhytoKeys </em>121: 43–51. https://doi.org/10.3897/phytokeys.121.30570</p>
<p>Hareesh, V.S. (2017) <em>Ophiorrhiza jacobii</em> (Rubiaceae) sp. nov. from Western Ghats, India. <em>Nordic Journal of Botany</em> 36: e01519. https://doi.org/10.1111/njb.01519</p>
<p>Hareesh, V. S. & Sabu, M. (2018) The genus <em>Ophiorrhiza </em>(Rubiaceae) in Andaman and Nicobar Islands, India with a new species. <em>Phytotaxa</em> 383 (3): 259–272. https://doi.org/10.11646/phytotaxa.383.3.3</p>
<p>Hooker, J.D. (1880 “1882”) Order LXXV. Rubiaceae. <em>In</em>: Hooker, J.D. (Ed.) <em>Flora of British India</em> 3 (7). Reeve, London, pp. 17–192. https://doi.org/10.5962/bhl.title.678</p>
<p>Korthals, P.W. (1851) <em>Ophiorrhiza</em> L. <em>Nederlandsch kruidkundig archief</em> 2: 122–133.</p>
<p>Linnaeus, C. (1753) <em>Species Plantarum</em> 1. ImpensisLaurentiiSalvii, Holmiae, 560 pp.</p>
<p>Liu, J., Pan, B., Li, S.W. & Xu, W.B. (2017) <em>Spiradiclisquanzhouensis</em>(Rubiaceae): A new species from limestone area in Guangxi, China. <em>NordicJournal of Botany</em> 36 (3): njb-01595. https://doi.org/10.1111/njb.01595</p>
<p>Li, J.-L., Yuan, Q., Liu, Y., Song, X.-F., Pan, B., Qu, C.-H. & Wu, L. (2021) Two new species of <em>Spiradiclis</em> (Rubiaceae) from limestone areas in southwestern China. <em>Nordic Journal of Botany</em> 39 (2): e02979. https://doi.org/10.1111/njb.02979</p>
<p>Lo, H.S., Sha, W.L. & Chen, X.X. (1983) A revision of the genus <em>Spiradiclis </em>Bl. <em>Acta Botanica Austro Sinica</em> 1: 27–36. [In Chinese]</p>
<p>Lo, H.S. (1990) Taxonomic revision of the Chinese species of <em>Ophiorrhiza</em> (Rubiaceae).<em> Bulletin of Botanical Research</em>, Harbin 10 (2): 1–82.</p>
<p>Lo, H.S. (1999) <em>Ophiorrhiza</em>. <em>In</em>: Lo, H.S. (Ed.) <em>Flora ReipublicaePopularisSinicae</em> 71(1). Science Press, Beijing, pp. 110–74 [In Chinese]</p>
<p>Pan, B., Tu, R.-H., Hareesh, V.-S. & Wu, L. (2019) <em>Spiradiclis cavicola</em> (Rubiaceae), a New Species from Limestone Caves in Southwestern China. <em>Annales BotaniciFennici</em> 56 (1–3): 1–4. https://doi.org/10.5735/085.056.0101</p>
<p>Raizada, M.B. & Bennet, S.S.R. (1982) Five new combinations and a new name for Indian flowering plants. <em>Indian Forester</em> 108 (4): 302–303. [https://www.i-scholar.in/index.php/indianforester/article/view/10823]</p>
<p>Rajan, R., Varghese, S.C., Kurup, R., Gopalakrishnan, R., Venkataraman, R., Satheeshkumar, K. & Baby, S. (2016) HPTLC-based quantification of camptothecin in <em>Ophiorrhiza</em> species of the southern Western Ghats in India. <em>Cogent Chemistry</em> 2 (1): 1275408. https://doi.org/10.1080/23312009.2016.1275408</p>
<p>Razafimandimbison, S.G. & Rydin, C. (2019) Molecular-based assessments of tribal and generic limits and relationships in Rubiaceae (Gentianales): Polyphyly of Pomazoteae and paraphyly of Ophiorrhizeae and <em>Ophiorrhiza</em>.<em> Taxon </em>68 (1): 72–91. https://doi.org/10.1002/tax.12023</p>
<p>Robbrecht, E. (1988) Tropical woody Rubiaceae. <em>Opera BotanicaBelgica</em> 1: 599–602.</p>
<p>Taher, M., Shaari, S.S., Susanti, D., Arbain, D. & Zakaria, Z.A. (2020) Genus <em>Ophiorrhiza</em>: A review of its distribution, traditional uses, phytochemistry, biological activities and propagation. <em>Molecules</em> 25 (11): 2611. https://doi.org/10.3390/molecules25112611</p>
<p>Tu, R.H., Li, J.L. & Wu L. (2018) <em>Ophiorrhiza gaoligongensis</em> (Rubiaceae), a new species from Southwestern China. <em>Novon</em> 26 (4): 351–354. https://doi.org/10.3417/2018309</p>
<p>Wang, R.J. (2016) <em>Spiradiclis jingxiensis </em>sp. nov. (Rubiaceae) from Guangxi, China. <em>Nordic Journal of Botany</em> 34 (5): 550–552. https://doi.org/10.1111/njb.01134</p>
<p>Wen, Z.-J., Yang, J.-C., Xu, Y.-F. & Wu, L. (2019) <em>Spiradiclis densa</em> sp. nov. (Rubaceae) from limestone areas in Guangxi, China. <em>Nordic Journal of Botany</em> 37 (5): e02190. https://doi.org/10.1111/njb.02190</p>
<p>Wu, L., Tong, Y., Pan, B. & Liu, Q.R. (2016) <em>Spiradiclis glabra </em>sp. nov. (Rubiaceae) from limestone areas in Guangdong, China. <em>Nordic Journal of Botany</em> 34 (6): 718–721. https://doi. org/10.1111/njb.01156</p>
<p>Wu, L., Hareesh, V.S. & Yu, Y.L. (2017) The taxonomic identity of <em>Ophiorrhiza rarior</em> and <em>O. mycetiifolia</em> (Rubiaceae). <em>Phytotaxa </em>299 (2): 261–266. https://doi.org/10.11646/phytotaxa.299.2.10</p>
<p>Wu, L., Tan, Y. H., Hareesh, V.S. & Liu, Q.R. (2018) <em>Ophiorrhiza macrocarpa</em> (Rubiaceae), a new viviparous species from Yunnan, southwestern China. <em>Nordic Journal of Botany</em> 36: e01637. https://doi.org/10.1111/njb.01637</p>
<p>Wu, L., Li, X., Liu, W.-J. & Liu, Q.-R. (2019a) <em>Spiradiclis karstana</em> (Rubiaceae), a new species from Yunnan, China. <em>PhytoKeys</em> 117: 1–8. https://doi.org/10.3897/phytokeys.117.28281</p>
<p>Wu, L., Wang, B.-M., Pan, B. & Yu, X.-L (2019b) <em>Spiradiclis tubiflora </em>(Rubiaceae), a new cave-dwelling species from southern China. <em>In</em>: Cai, J., Yu, W.-B., Zhang, T., Li, D.-Z. (Eds.) Revealing of the plant diversity in China’s biodiversity hotspots. <em>PhytoKeys </em>130: 217–224. https://doi.org/10.3897/phytokeys.130.34625</p>
<p>Yang, C.-D., He, X.-Z. & Gou, G.-Q. (2018) <em>Ophiorrhiza guizhouensis</em> (Rubiaceae), a new species from Guizhou Province, southwestern China. <em>PhytoKeys </em>95: 121–126. https://doi.org/10.3897/phytokeys.95.22506</p>