Inflorescence morphology and systematics of the genus Thottea Rottb. (Aristolochiaceae) from the Western Ghats, India

Abstract

Inflorescence morphology was analysed for 21 accessions of the genus Thottea from the Western Ghats, with respect to systematic relationships. A variety of statistical procedures were used (one‐way ANOVA, UPGMA clustering, Principal Component Analysis and Principal Coordinate Analysis) for species characterisation and also for identifying the reliable species delimiting inflorescence features. Based on the analysis of 12 qualitative and three quantitative morphological characters, two species lineages have been identified within the genus. The first lineage, with T. abrahamii and T. dinghoui, while the second one with the remaining six species (T. barberi, T. duchartrei, T. idukkiana, T. ponmudiana, T. siliquosa and T. sivarajanii). Thottea ponmudiana is unique in the second species lineage due to its very special inflorescence features. Inflorescence morphology failed to provide a systematic key for distinguishing T. abrahamii from T. dinghoui, and T. duchartrei from T. idukkiana. Principal Component Analysis revealed the taxonomic significance of all the three quantitative and nine qualitative features.

Key words:

• dendrogram
• inflorescence shoot
• morphometric analysis
• partial florescence
• prophyll
• Thottea

Notes

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