Dipcadi saxorum

The distribution of D. saxorum is considered to be in ten major subpopulations spread out in the four different states of India. From Maharashtra, the species is represented by seven subpopulations (locations), four of which are in the Mumbai and Thane districts that lie adjacent to each other.

Sanjay Gandhi National Park (Mumbai Suburban), has Buddhist caves with rooftop plateaus. Dipcadi saxorum can be found on two of the plateaus as four distinct groups where there is little exchange of germplasm (subpopulations). The population pattern on these plateaus is such that that the density of this species is highest at the beginning of the westward slopes and decreases as we move to the extreme west and east of the plateaus. Two of these four subpopulations are regularly visited by tourists. The other two are not frequented by tourists, however, there are fewer individuals of D. saxorum in these subpopulations (quadrat: avg. 7 individuals/sqm).

Manori (Mumbai Suburban) is a plateau located immediately adjoining the Arabian Sea and hence it is buffered by strong winds. This plateau has soil which consists mainly of sand and rocks. Manori plateau is a privatized land and developmental activities have started on this land (quadrat: 45 individuals/sqm).

Uttan (Thane) has a small village called Dongri which has many hillocks. This region has mango orchards. D. saxorum here grows in shades of mango trees on these orchards and open hillocks as well. This population of D. saxorum is the only dense population when compared to all other studied sites for the species (quadrat: 98 individuals/sqm).

Literature study reveals more locations of D. saxorum: namely, Baramati (Shimpale et al. 2008), Solapur (Gaikwad and Garad 2015), Shoolpaneshwar Wildlife Sanctuary (Purohit and Solanki 2019), Mount Abu (Kulloli 2020) and Dhoopgarh (quadrat: 5 individuals/sqm). Mount Abu and Dhoopgarh have a scanty population and are tourist destinations threatened by anthropogenic activities.

More than 80% of the subpopulations of D. saxorum occur as clumps widely separated by 10 or more kilometres. There are no large and continuous populations, and the subpopulations are likely to be too small to be viable in the long term indicating that D. saxorum has a severely fragmented population state. The seeds do not disperse over large distances.