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Bromeliaceae family

Pitcairnia bifrons (Lindley) R.W. Read, Phytologia 19: 277. 1970
Bas.: Billbergia bifrons Lindley (1853).

Kawata. Zannanna djab, mawon, gran bwa.
Lesser Antillean endemic
Quite common terrestrial herb of elfin shrublands.
St. Kitts, Guadeloupe, Martinique, St. Lucia.

More branched forms are found in more sheltered spots in the elfin shrublands and on exposed ridges at about 700m elevation in the  Mount Gimie area. They may be hybrids between P. bifrons and P. angustifolia.

Another explanation is that P. bifrons and P. angustifolia and the intermediate forms are a single variable taxon, P. angustifolia.
DNA analysis would be very interesting!