Vegetos
(An International Journal of Plant Research & Biotechnology)
(eISSN: 2229-4473)
Morphological plasticity and threat assessment of primitive pteridophytes in Palakkad gap of Western Ghats, India
*Article not assigned to an issue yet
Alen Alex Philip, Abhilash Kalathil Sethumadhavan, Gayathri Thekkekara Suresh, Leeja Lakshmanan
Research Articles | Published: 15 June, 2026
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Keywords: Pteridophytes, Ferns, Lycophytes, Palakkad, Western Ghats
Abstract
The Palakkad Gap, a crucial geological feature in India's southern Western Ghats, is home to seventeen primitive pteridophytes, which are the most ancestral forms of vascular cryptogams. These pteridophytes are singularly and variably dispersed among the many ecological niches. Intense anthropogenic habitat fragmentation in this area is made worse by challenging climate factors such as extended dry spells and fluctuating temperature regimes. Because of their severe habitat sensitivity and limited reproductive success in disturbed habitats, these forces increase the survival risk of primitive pteridophytes. To accurately estimate the extinction risk and assess the adaptive morphological responses of these ancestral species inside the Palakkad Gap, a Rapid Threat Assessment (RTA) was carried out alongside a morphometric analysis. In species occurring in the adverse environmental zone, morphometric studies showed a constant drop in plant dimensions (such as frond length) along with an increase in strobili length, suggesting adaptive morphological alterations towards reproductive prioritisation under stress. The prioritisation of asexual reproduction under environmental stress was confirmed by morphometric analysis, which showed a measurable adaptive shift in the severe environmental zone. This shift was characterised by a continuous decrease in vegetative dimensions and an increase in reproductive allocation. Six species were classified under very high threat in RTA due to their acute habitat specificity and extremely low plant population densities. The findings show that these environmentally fragile species in the Palakkad gap of the southern Western Ghats need immediate conservation attention.
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Author Information
Department of Botany, Government Victoria College, Palakkad, University of Calicut, India