Skip to main navigation menu Skip to main content Skip to site footer
Plant Science Today (PST)

Research Articles

Vol. 13 No. 3 (2026)

Deciphering Phenetic Relationships Among Thunbergia Species of Northeast India Through Integrative Numerical Taxonomy

DOI
https://doi.org/10.14719/pst.13932
Submitted
1 February 2026
Published
01-07-2026 — Updated on 09-07-2026
Versions

Abstract

An integrative numerical taxonomy approach was used to investigate the phenetic relationships among 6 species of the genus Thunbergia (Acanthaceae) native to Assam, India: Thunbergia erecta Nees., Thunbergia alata Bojer ex Sims,  Thunbergia fragrans Roxb., Thunbergia coccinia Wall., Thunbergia laurifolia Lindl. and Thunbergia grandiflora Roxb. which were examined from February 2023 to January 2025 which were collected from various district of Assam, India. The observation sheet that was uploaded contains descriptions of vegetative, floral, stomatal, trichome, stem anatomical and pollen characteristics for each of the species. The multistate traits were converted to a binary-compatible matrix and the continuous traits were standardised before phenetic analysis. Two main groups were revealed by the average-linkage clustering analysis. The first group comprised the species with the larger laminae and the second main group comprised the species with the smaller laminae. However, T. erecta was found to be separate from the other 5 species as it has a shrubby growth habit, shorter stature and a different stem morphology. Thunbergia coccinia and T. laurifolia were most similar to each other, though T. grandiflora was most remote from the other 5 species due to its larger lamina, petiole length and corolla dimensions. The integration of these different characteristics allows for a better understanding of the relationships between the species and forms the basis for future analyses in software like SPSS or other multivariate analyses.

References

  1. 1. Scotland RW, Vollesen K. Classification of Acanthaceae. Kew Bull. 2000;55(3):513–89. https://doi.org/10.2307/4118776
  2. 2. Schönenberger J, Endress PK. Structure and development of the flowers in Mendoncia, Pseudocalyx and Thunbergia and their systematic implications. Int J Plant Sci. 1998;159(3):446–65. https://doi.org/10.1086/297563
  3. 3. Schönenberger J. Floral structure, development and diversity in Thunbergia. Bot J Linn Soc. 1999;130(1):1–36. https://doi.org/10.1111/j.1095-8339.1999.tb00779.x
  4. 4. McDade LA, Daniel TF, Kiel CA. Toward a comprehensive understanding of phylogenetic relationships among lineages of Acanthaceae s.l((Lamiales). Am J o Bot. 2008;95(9):1136–52. https://doi.org/10.3732/ajb.0800096
  5. 5. Borg AJ, McDade LA, Schönenberger J. Molecular phylogenetics and morphological evolution of Thunbergioideae. Taxon. 2008;57(3):811–22. https://doi.org/10.1002/tax.573012
  6. 6. Tripp EA, McDade LA. A rich fossil record yields calibrated phylogeny for Acanthaceae. Syst Biol. 2014;63(5):660–84. https://doi.org/10.1093/sysbio/syu029
  7. 7. Manzitto-Tripp EA, Darbyshire I, Daniel TF, McDade LA, Kiel CA. Revised classification of Acanthaceae. Taxon. 2022;71(1):103–53. https://doi.org/10.1002/tax.12600
  8. 8. Anderson T. An enumeration of the Indian species of Acanthaceae. J Linn Soc Lond Bot. 1867;9:425–526. https://doi.org/10.1111/j.1095-8339.1867.tb01308.x
  9. 9. Clarke CB. Thunbergia. In: Flora of British India. Vol. 4. London: L. Reeve & Co.; 1885. p. 390–3.
  10. 10. Scotland RW. Systematics, similarity and Acanthaceae pollen morphology. Bot J Linn Soc. 1992;109(4):529–41. https://doi.org/10.1111/j.1095-8339.1992.tb01449.x
  11. 11. Sokal RR, Sneath PHA. Principles of Numerical Taxonomy. San Francisco: W.H. Freeman; 1963.
  12. 12. Sneath PHA, Sokal RR. Numerical taxonomy. Nature. 1962;193:855–60. https://doi.org/10.1038/193855a0
  13. 13. Royal Botanic Gardens, Kew. Thunbergia laurifolia. Plants of the World Online. https://powo.science.kew.org/
  14. 14. Rohlf FJ. NTSYSpc: Numerical Taxonomy and Multivariate Analysis System. Exeter Software; 2005.
  15. 15. Khaleghi A, Khadivi A, Tunç Y. Multivariate analysis of Iris meda. PLoS One. 2025;20:e0336783. https://doi.org/10.1371/journal.pone.0336783
  16. 16. Karbstein K, Kösters L, Hodač L, Macek M, Smith A, Johnson B, et al. Species delimitation 4.0. Trends Ecol Evol. 2024;39(8):771–84. https://doi.org/10.1016/j.tree.2023.11.002
  17. 17. Hunt R, Reyes-Hernández JL, Shaw JJ, Brown T, Wilson P, Garcia M, et al. Integrating deep learning derived traits. Syst Biol. 2025;74(3):453–68. https://doi.org/10.1093/sysbio/syae072
  18. 18. Zaman W, Ayaz A, Park S. Integrating morphological and molecular data. Pak J Bot. 2025;57(4):1453–66. https://doi.org/10.30848/PJB2025-4(27)
  19. 19. IBM. Hierarchical Cluster Analysis (SPSS documentation). 2025.
  20. 20. Sokal RR, Rohlf FJ. Comparison of dendrograms. Taxon. 1962;11(2):33–40. https://doi.org/10.2307/1217208
  21. 21. Dalawai D, Murthy HN. Pollen and seed morphology. Grana. 2021;60(6):459–76. https://doi.org/10.1080/00173134.2021.1910726
  22. 22. Zakaria SM, Amri CNAC, Talip N, Juhari AAA, Rahman MRA, Zohari AF, et al. Comparative leaf anatomy of Thunbergia. Trop Life Sci Res. 2022;33(1):105–19. https://doi.org/10.21315/tlsr2022.33.1.7
  23. 23. Raza J, Ahmad M, Zafar M, Athar M, Sultana S, Majeed S, et al. Comparative foliar anatomy. Microsc Res Tech. 2020;83:1–15. https://doi.org/10.1002/jemt.23502
  24. 24. Do VH, Nguyen TT, Bui HQ, Duong TH, Choudhary RK, Deng Y. Notes on Thunbergia in Vietnam. Phytotaxa. 2025;697(3):255–64. https://doi.org/10.11646/phytotaxa.697.3.4
  25. 25. Royal Botanic Gardens, Kew. Thunbergia grandiflora. Plants of the World Online.
  26. 26. Borah D, Ahmed N, Wood JRI. Strobilanthes sherdukpenorum. Gard Bull Singapore. 2025;77(1):141–8. https://doi.org/10.26492/gbs77(1).2025-11
  27. 27. Mani B, Thomas S, Pradeep AK, Kumar ESS. Strobilanthes brittoi. Rheedea. 2024;33(4):350–8. https://doi.org/10.22244/rheedea.2023.33.04.06
  28. 28. Diksha K, Satheshkumar C, Rana TS, Prabhukumar KM. Gymnostachyum mundanthuraiensis. Taiwania. 2025;70(1):55–7. https://doi.org/10.6165/tai.2025.70.55
  29. 29. Dharap AV, Shigwan BK, Datar MN. Dicliptera polymorpha. Kew Bull. 2024;79(3):683–92. https://doi.org/10.1007/s12225-024-10203-6
  30. 30. Giri S, Saha P. Anti-inflammatory flavonoids. Indian J Nat Prod Resour. 2025;16(2):209–26. https://doi.org/10.56042/ijnpr.v16i2.15820
  31. 31. Srimawong C, Torkaew P, Putalun W. Polyphenol extraction. RSC Adv. 2025;15(27):22086–96. https://doi.org/10.1039/D5RA02501J
  32. 32. Pechdee P, Arunsan P, Boonsuya A, Thanchonnang C, Phinsiri S, Rattanapitoon NK, et al. Efficacy of Thunbergia laurifolia crude extracts. Trop Biomed. 2025;42(1):65–75. https://doi.org/10.47665/tb.42.1.012
  33. 33. Maung YL. Botanical investigation on Thunbergia laurifolia. J Myanmar Acad Arts Sci. 2023;21:371–80.
  34. 34. Bevilacqua S, Anderson MJ, Ugland KI, Somerfield PJ, Terlizzi A. Taxonomic relationships in ecology. Austral Ecol. 2021;46:950–64. https://doi.org/10.1111/aec.13061

Downloads

Download data is not yet available.