Gingersrus Database Taxon ID 7611
OLD NAME: Costus laevis - maximus form
NEW NAME: Costus kuntzei
NAME CHANGE NOTES: former C. laevis from Atlantic side of Central America like synonym Costus maximus
FULL SCIENTIFIC NAME:
STATUS : distinct form
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PHOTOS:(If photos are available, you can click on the link to open in a new window.)
This form of Costus kuntzei is characterized by a shorter, truncate ligule and usually has thick short hairs around the ligule. It is a more massive plant than the "skutchii" form at PID7610. The basal ligules (lacking leaves) are glabrous and bulge outward distinctively. The young inflorescence is globular in shape and the bract colors are usually mostly green, and not red or dark purple. This form is found on the Caribbean side of Costa Rica and Panama, and also in the central mountain regions of Costa Rica to the north of Puntarenas province.
I am basing this grouping on the plant form as collected in 1898 by A. Tonduz at Tucurrique in Cartago province along the Rio ReventazÃ³n. The plant was originally described as Costus gigantea Kuntze and renamed as Costus maximus Schumann as the epiphet "giganteus" had already been used for an African plant (Costus giganteus Welw. ex Ridl. It may well be that this form is also the form of the Guatemalan plant that was described and named as Costus splendens.
I have been to the Tucurrique area and have seen these plants at the nearby Reserva La Marta and other areas on the Caribbean side (east of the Talamancas of Costa Rica) and Panama. Photos and observations of this form are included on this page. Note that some of these plants from the La CangrÃ©ja area in Puriscal (just to the north of Puntarenas) seem to be intermediate between the two forms but I have somewhat arbitrarily grouped them here. All those from Puntarenas are grouped in the skutchii group, PID 7610.
A partial phylogeny was completed by Eugenio Valderrama and his associates in the Chelsea Specht Lab at Cornell University and was published in the journal Frontiers in Plant Science in September 2022. R3035 from this form was included in the molecular phylogeny and was well supported in the clade with the skutchii form, so this is probably NOT a separate species.
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