1986) Croat-Venezuela Araceae 3 The Araceae of Venezuela by Thomas B. Croat1 and Nancy Lambert2 lMissouri Botanical Garden, P.O. Box 299, Sf. Louis, MO 63166 2154 Union Street, Manchester, N.H. 03104 Abstract: An illustrated treatment of 171 Venezuelan Araceae taxa is provided. Discussion of range, species characteristics and distinction from similar or closely related species is made for each taxon. Sixteen species, three subspecies and one variety are described as new, and three new combinations are made. Until recently the Araceae of Vene­ trips in recent years have enabled me to zuela was very poorly known, but that photograph a good percentage of the has greatly changed with the publication species in the Flora. These trips included of "Sinopsis de las Araceaes de Venezu­ a month long trip (July-August) in 1982 ela" by G. S. Bunting (Rev. Fac. Agron. which took me more than 6,000 (Maracay) 10:139-290. 1979). This great kilometers by car and 2,000 kilometers contribution to our understanding of by air into many parts of the country. A the South American Araceae is the second 3 week long trip to Cerro result of about 20 years of work by Bunt­ Neblina (Nov-Dec, 1985) in the Ter­ ing in Venezuela. Since the work was ritorio Amazonas on the Brazilian published in Spanish, lacks illustrations border was followed by a trip to the and is likely to be unavailable to most Cordillera de la Costa and the Cordillera aroid enthusiasts, I will present here de Merida during two weeks in March some needed commentary on the Vene­ of 1986. In all, I was able to collect a zuelan species and will illustrate many high percentage of the 274 aroid taxa of them for the first time. occurring there. All described Venezuelan species are The aroid flora of Venezuela is inter­ listed in appendix 1. When species are esting in several ways. It is apparently new to science or recently described much richer in species than the Amazon elsewhere complete descriptions are basin to the south but less rich than the provided. The species discussed in the species-rich western Cordillera of text are generally only those for which Colombia to the west. The aroid flora illustrations were available. Where of Venezuela is similar to the flora of species were sufficiently known to the middle Amazon basin, howevPf, in provide commentary, but where no that it is substantially richer in species photographs of live material was avail­ of Philodendron than Anthurium. In able, photographs of typical herbarium countries throughout most of the material has sometimes been provided. Western Andes, Anthurium species While herbarium specimens are generally outnumber Philodendron generally unsuitable for easy recogni­ species. For example, in Panama there tion by horticulturists, they at least are 158 known species of Anthurium provide some assistance in indentifi­ and about 75 species of Philodendron. cation. In contrast, a typical locality in Many of the Venezuelan species, Amazonian Brazil may have many spe­ including many poorly known or rare cies of Philodendron and no represen­ species described for the first time by tation of Anthurium. Even when Bunting, are very attractive and will be Anthurium are present they are often in demand by horticulturists. Several rare, most being members of section 4 Aroideana (Vol. 9(1-4) Pachyneurium (bird's nest Anthuriums). the species is known to occur are also The situation in Venezuela is not nearly listed in an abbreviated manner as severe, but even so, 66 species of according to the following: Philodendron are reported by Bunting Amazonas Am while only 44 species of Anthurium Anzoategui An were reported. Apure Ap Venezuela is quite diverse geo­ Aragua Ar graphically, with several distinct Barinas Ba geological components appearing to Bolwar Bo have arisen at different times, or at Carabobo Ca least to have been isolated for a con­ Cojedes Co siderable time, resulting in distinct Delta Amacuro DA floristic regions. Bunting (1979) divided Distrito Federal DF Venezuela into seven floristic zones Falcon Fa (Fig. 1) in regard to the distribution of G~rioo Gu aroids. These were: 1. The Atlantic Lara La coast (territory of Delta Amacuro and Merida Me the eastern extremes of Sucre and Miranda Mi Bolivar States). 2. The Cordillera de la Monagas Mo Costa of the Federal District and States Nueva Esparta NE of Miranda, Aragua and Carabobo with Portuguesa Po extentions or subzones in the eastern Sucre Su states of Sucre and Monagas, as well as Tachira Ta the western states of Varacuy and Trujillo Tr Falcon. 3. The Cordillera de Merida Varacuy Va and the Sierra de Perija, the two moun­ Zulia Zu tain chains lying on either side of Lake Maracaibo. 4. The forested slopes below The legend of those species chosen the Paramo de Tama in SW Tachira (with for illustration includes more specific a flora related to the western Andes of information. Colombia). 5. The Amazon lowland region. 6. The Guyana Highlands. 7. The Llanos (flat grasslands and savannas of the Orinoco drainage). Relatively few Araceae occur in the Llanos, which are partially flooded during the rainy season and very dry during the dry season. The zone probably richest in Araceae per unit area is the Cordillera de Merida, per­ haps owing to its much more diverse array of elevations and habitats. Appendix 1 lists the 275 taxa of Araceae trom Venezuela. Each species has been assigned to one or more of these floristic regions by number only. In a few cases, name changes have been made or have been suggested. Some taxa have been added to the flora. These are preceded by an asterisk. The states or territories of Venezuela where 1986) Croat-Venezuela Araceae S Fig. 1. the floristic regions of Venezuela: 1." t~e Atlantic ~oast 2. t~~ Cordillera de la Costa 3. the Cordillera de Menda and the SIerra de PenJa 4. SW Tachira below Tama S. the Amazon region 6. the Guyana high­ lands 7. the Llanos (not shown). Anthurium amoenum is apparently ANTHURIUM endemic to Venezuela, ranging from the Cordillera de la Costa lEI Avila in Anthurium acrobates Sodiro, Anales the Distrito Federal to Alto de Choron! Univ. Centro Ecuador 16: 276. 1902. in Aragua) to the Cordillera de Merida Anthurium acrobates ranges from (from Barinas and Merida (La Azulita) southern Colombia (Meta) along the to Sierra de San Luis in Falcon) at 1,420- eastern slopes of the Andes to 2,140 m, generally occurring inSMdy, Ecuador and Peru at elevations of wet undisturbed areas. Fig. 4 280-2,SOO m. A recent outlying The species is characterized by its collection from southern Amazonas at terrestrial habit, short internodes (6-20 Cerro Neblina indicates that at one time mm diam.), deciduous cataphylls, and a the species may have had a broader subterete petiole that is weakly and distribu~ion. Figs. 2-3 narrowly flattened toward the apex, The species is recognized by its more consciously so on the geniculum. appressed-climbing habit with elongate The blades are thin and veiny, elliptic to internodes, long-petiolate, narrow, broadly elliptic, with the principal veins ovate to ovate-triangular blades, and mostly sunken above and raised below. its long-pedunculate inflorescences with The secondary and tertiary veins are also a green, lanceolate spathe and usually raised on the lower surface and the purplish, long-tapered spadix. lower midrib is often tinged red. The erect inflorescence has a green spadix Anthurium amoenum Kunth & with medium green tepals, a green re­ Bouche, Ind. Sem. Hort. Berol. flexed spathe, and dark green, early 1848: 1. 1848. emergent pistils. 6 Aroideana (Vol. 9(1-4) Figs. 2-5. 2-3. Anthurium acrobates Sod iro. Ecuador. Napo: Baeza, 2500 m, Croa t 49437. 2. Habit, x1/ 12. 3. Inflorescence, x3 / 10. ----4. A. amoenum Kunth & Bouche. Venezuela. Merida: Merida - La Azulita, 1590 m, Croat 54875. Habit, xl/ 5. ----5. A. betanianum Croat. Venezu­ ela. Tachira: Tama National Park, 2600 m , Croat 60687A. Inflores ­ cence, xl/ 6. 1986) Croat-Venezuela Araceae 7 Engler included A. humile Schott ficial ways from that of Central America, from Peru as a variety of this species. but considering the widespread nature Despite the fact that the Schott drawings of the species in Central America, it is of A. humile look very similar to not surprising to find it in eastern South A. amoenum, it is unlikely, consider­ America. ing known distributional patterns, that The species is distinguished by its the Peruvian plants are closely related short internodes, long- petiolate, ob­ to the Venezuelan species. long-oblanceolate blades with a distinc­ tive sunken collective vein, which is Anthurium apaporanum Schultes, Bot. more conspicuous than the primary Mus. Leafl. Harvard Univ. 18: 115, lateral veins. In this regard, the species pI. 19. 1958. is close to A. ange/orum Bunting, having Anthurium apaporanum ranges from similar blades. That species, however, southern Venezuela to southern Colom­ dries grayish green and is reported to bia (Vaup~s) and south along the foot­ have a greenish yellow spadix (Davidse hills of the Andes to Ecuador (Napo and et al. 18530), while A. bakeri has blades Pastaza) and Peru (Amazonas, Loreto, drying yellow-green and has a white Huanuco and Pasco) at 200-1,000 m. In spadix. Venezuela, it is known only from Cerro Perhaps the closest relative of A. Neblina, but it is expected to range bakeri in Venezuela is A. apaporanum throughout the remainder of southern Schultes. The latter species, repre­ Venezuela. Fig. 6 sented by an outlying population in The species is a member of section Venezuela at Cerro Neblina, ranges Porphyrochitoniuro and is distinguished from Colombia to Peru.