Abstract2

A REVISION OF PHILODENDRON SUBGENUS PHILODENDRON (ARACEAE) OF CENTRAL AMERICA

Abstract:

This revision is the first revision of Philodendron subg. Philodendron since that of K. Krause in Das Pflanzenreich in 1913. Philodendron subg. Philodendron, the largest of the three subgenera, includes 103 taxa, including 95 species and 8 additional subspecies or varieties for Central America. A total of 65 taxa are new to science. These include 59 species: P. advena Schott, P. alticola Croat & Grayum, P. annulatum Croat & Grayum, P. antonioanum Croat, P. aromaticum Croat & Grayum, P. bakeri Croat & Grayum, P. breedlovei Croat, P. brewsteriense Croat, P. brunneicaule Croat & Grayum, P. chiriquense Croat, P. chirripoense Croat & Grayum, P. clewellii Croat, P. coloradense Croat, P. copense Croat, P. correae Croat, P. cotobrusense Croat & Grayum, P. cotonense Croat & Grayum, P. crassispathum Croat & Grayum, P. cretosum Croat & Grayum, P. dodsonii Croat & Grayum, P. dolichophyllum Croat, P. dominicalense Croat & Grayum, P. dwyeri Croat, P. edenudatum Croat, P. ferrugineum Croat, P. findens Croat & Grayum, P. folsomii Croat, P. fortunense Croat, P. gigas Croat, P. granulare Croat, P. grayumiiCroat, P. hammelii Croat, P. heleniae Croat, P. jefense Croat, P. knappiae Croat, P. lazorii Croat, P. lentii Croat & Grayum, P. llanoense Croat, P. madronoense Croat, P. malesevichiae Croat, P. morii Croat, P. niqueanum Croat, P. pirrense Croat, P. pseudoauriculatum Croat, P. purulhaense Croat, P. roseospathum Croat, P. scalarinerve Croat & Grayum, P. sousae Croat, P. squamicaule Croat & Grayum, P. squamipetiolatum Croat, P. straminicaule Croat, P. sulcicaule Croat & Grayum, P. thalassicum Croat & Grayum, P. tysonii Croat, P. ubigantupense Croat, P. utleyanum Croat, P. verapazense Croat, P. wilburii Croat & Grayum, P. zhuanum; 6 new subspecies or varieties: P. davidsonii var. bocatoranum Croat, P. hederaceum (Jacq.) Schott ssp. kirkbridei Croat, P. ligulatum Schott var. heraclioanum Croat, P. ligulatum Schott var. ovatum Croat, P. roseospathum Croat var. angustilaminatum Croat; P. wilburii var. longipedunculatum Croat & Grayum; and 2 new combinations: P. hederaceum (Jacq.) Schott ssp. oxycardium (Schott) Croat, P. radiatum Schott var. pseudoradiatum (Matuda) Croat. Philodendron subg. Pteromischum, revised separately by M. H. Grayum (Grayum, 1996) contains 24 species (including 25 taxa) for Central America. Thus, there is a total number of 119 species, including 128 taxa, of Philodendron in Central America. The P. subg. Meconostigma revised recently by Mayo (Mayo, 1991) has no Central American species. Species diversity of P. subg. Philodendron in Central America shows a general diminution from Mexico to Middle America, followed by a marked increase closer to South America. Mexico has 21 taxa, Guatemala 15, Belize 9, El Salvador 5, Honduras 13, Nicaragua 18, Costa Rica 49, and Panama 80 taxa respectively. Endemism is high, especially for Panama where 39 taxa are currently considered endemic. Mexico and Costa Rica each have 7 endemic species. With the exception of Belize, which has one endemic, no other country in Middle America has any endemic species. Central American species of P. subg. Philodendron are not markedly related to those of South America. Only 25 species (26 taxa) (a total of 25% of all Central American species range into South America, six species (7% of the total) only to Colombia. Fourteen taxa occur in Ecuador primarily ranging along the Pacific slope of the Andes. Seven species range to Venezuela while three of the same also extend into the Amazon drainage. Only four species occur east of the Andes and also in the Amazon drainage. Three additional species occur east of the Andes but exist only along the Cordillera de Merida, the Cordillera de la Costa or in the northern part of the Guiana Highlands and within the drainage of the Río Orinoco not in the Amazon basin.

Abstract:

This revision is the first revision of Philodendron subg. Philodendron since that of K. Krause in Das Pflanzenreich in 1913. P. subg. Philodendron, the largest of the three subgenera, includes 104 taxa, including 96 species and 8 additional varieties for Central America. A total of 66 taxa are new to science. These include 59 species and 7 varieties. P. subg. Pteromischum, revised separately by M.H. Grayum (Grayum, 1996) contains 24 species (including 25 taxa) for Central America. Thus there is a total number of 120 species, including 129 taxa, of Philodendron in Central America. The P. subg. Meconostigma revised recently by Mayo (Mayo, 1991) has no Central American species. Species diversity of P. subg. Philodendron in Central America shows a general diminution from Mexico to Middle America, followed by a marked increase closer to South America. Mexico has 21 taxa, Guatemala 15, Belize 9, El Salvador 5, Honduras 13, Nicaragua 18, Costa Rica 50, and Panama 79 taxa respectively. Endemism is high, especially for Panama where 37 taxa are currently considered endemic. Mexico has 15 endemic species while Costa Rica has 9 endemic species. With the exception of Belize, which has one endemic, no other country in Middle America has any endemic species.