Anthuriums are Not Just Foliage Plants and Cutflowers
Since anthurium became popular as ornamental plants, species being cultivated have been grouped to either foliage-type anthurium or cutflower-type anthurium only. Foliage-type anthuriums have handsome, velvety or shiny leaves with inconspicuous floral structures (inflorescenses) while cutflower-type anthuriums bear beautiful flower or inflorescences and ordinary leaves. With such general classification, it becomes difficult to identify which group do Pearl anthurium and Mickey Mouse anthurium belong.
Recently, there was a sudden surge in demand for planting materials of different species of anthurium. Buyers from other countries, were looking for specimen plants for sale or for propagation. Apparently, these plants will be used for developing new or improved varieties by hybridization.
I was informed that these developments in Asia is attributed to the dreaded disease of anthuriums: bacterial blight, that infected not only the stock plants being, used for micropropagation and seed production, but also the tissue cultured plants in South America and United States.
In the world market, the demand for anthurium planting materials is not high. And anthurium breeders and tissue-culturists could not introduce new hybrids or improved varieties. I heard that natural sources of variation (biodiversity) for plants have already been exhausted, if not depleted, so the artificial means of creating new varieties for the market is the alternative. However, there are almost 1,000 species of anthurium and only a small fraction of it has been cultivated or traded so far. Reports posted on the internet say that there are 1,500 species but I believe that it includes the synonyms or varieties of each species considered valid. If we also count the registered hybrids of these species, there would be a lot more.
After more than 175 years since Heinrich W. Schott established the genus Anthurium in 1829, new species are still found in their natural habitat from northern Mexico and the Greater Antilles to southern Brazil, northern Argentina, and Paraguay. Among the new species that were reported in 2005 are A. curicuriariense Croat and A. santaritensis Nadruz and Croat -that could be found only in Brazil, their native habitat.
Many newly collected species are still being identified or just awaiting publication as species novum. Elsewhere, anthuriums are introduced so there is no species native to the Philippines. Specimens occasionally found in the wild are actually seedlings of cultivated plants whose seeds have been disseminated by birds after eating the ripe fruits.
Bird’s nest anthuriums have been observed to be more adaptive and tolerant of lowland and indoor conditions than bird’s nest ferns (Asplenium nidus, A. musifolium, etc.) and bird’s nest philodendrons (Philodendron wendlandii, PP insigne, etc.). Meanwhile, the spathes of the new cultivars of Anthurium andraeanum, A. scherzerianum, and the interspecific hybrids come in different colors. Their inflorescences, as cutflowers, last longer and even potted plants can continuously produce these. What if somebody specialized in improvement of this genus? It would be difficult for there are so many kinds, you would not know how to prioritize. If someone is interested in coming up with an ideal anthurium variety, he or she should concentrate on a certain group or section.
CLASSIFICATION AND GENERAL CHARACTERISTICS
The genus had been re-classified into just 18 sections. Four sections were subdivided into two series or subsections each to group together species that are more related to each other or share similar characteristics as compared with another section. Listed below in no definite order are the different sections of Anthurium.
Section Pachyneurium. This approxi mately has 115 species. Members have short, densely rooted $tem and rosulate leaves so they are commonly called bird’s nest anthuriums as they resemble the bird’s nest fern (Asplenium nidus). In bud stage, the leaf margins are rolled inward toward the midrib (involute vernation).
There are two series. Pachyneurium has blades with primary lateral veins much conspicuous than the interprimary veins and usually dry brown, reddish brown, greenish brown or blackened. The Multinervia, on one hand, has blades with many interprimary veins which are almost as conspicuous as the primary lateral veins and usually dry green or yellow-green.
The popular examples of series Pachyneurium are A. affine, A. crassinervium, A. plowmanii, A. spectabile, A. superbum and A. watermaliense, while representatives of series Multinervia are A. fasciable, A. napaeum, and A. obscurinervium.
Anthurium hookerii, a bird’s nest anthurium excluded in Section Pachyneurium, may end up in a section of its own because of its convolute vernation and it has ladder-like secondary- lateral veins on the leaves. In bud stage, one margin is rolled inward toward the midrib while the other is margin rolled around the midrib. On one hand, the rolled up opposite margin is like a continuous coil in cross section.
Section Semaeophyllum. The Mickey Mouse anthuriums have leaves with three lobes that are united at the base. Popular examples are A. garagaranum, A. insigne, and A. subsignatum.
Section Schizoplacium. The species that belong in this section have palmately-lobed leaves. Anthurium palmatum, A. pedatoradiatum, and A. podophyllum are commonly called Finger-leafed anthuriums although the lobes, which are united at the base or the middle one is free, may be more than five.
Section Dactylophyllum. This group of anthuriums is characterized by leaves with three or more lobes free to the base. Examples are A. pentaphyllum, A. triphyllium, and A. trisectum. Likewise, this group is commonly called Fingerleafed anthurium even if some have only three “fingers.”
Section Digitinervium. Its anthuriums have thick leaf blades with glandular punctuations or dark dots and two or more pairs of steepy ascending basal veins. Anthurium crassifolium, A. lentii, and A. ovatifolium are the typical examples. No common name has been given to this group.
Section Tetraspermium. It is composed of the Pearl anthuriums, A. scandens and A. obtusum, that are self-pollinating because the receptive stigmas are only two to three spirals ahead of the emerging stamens and the anthers are held against the pistil at same level as emerged pistil when pollen is shed. One or both surfaces of the leaf blade are conspicuously glandular-punctate and the stems are slender, climbing and composed of long internodes.
Section Porphyrochitonium. This is the largest with about 250 species and the group with probably the most species new to science. The species are characterized by dark glandular dotting on leaf blades that are never heart-shaped but have one or more prominent collective veins along the margin. The stems are generally slender with short internodes, and most plants are relatively small.
Examples are A. bakeri, A. scherzeriunum, and A. wendlingerii, that belong to the first group, and A. amnicola, A. anrioquiense and A_ antrophyoides, that belong to the second group. Species of the second group cross more readily amonL, themselves as well as with the species of Section Calomystrium than with members of the first group.
Section Calomystrium. A. andraea num, which has heart-shaped leaves that are not velvety but usually smooth and semi-glossy to glossy belongs to this section. The stem of this species bears conspicuous, thick, intact, persistent cataphylls or leaf sheaths that are reddish-brown to brown when dry. Other members include A. armeniense, A. kamemotoanum, A. ravenii, A. roseospadix, and A. veitchii, the King anthurium.
Section Belolonchium. The species have leaf blades that may be hastate, heart-shaped or with usually definite posterior lobes. Their cataphylls are also deciduous or weather into a mass of fibers. One group, where A. brownii, A. concinnatum, and A. rigidifolium be long, has relatively leathery leaf blades that dry brown. Another group, where A. lancitillense, A. ovandense, and A. umbrosum are members, has dry green thinner leaf blades.
Section Cardiolonchium. The anthuriums that belong to this section have metallic green, heart-shaped velvety leaves. Foliage-type anthuriums such as A. crystallinum or Crystal anthurium, A. magnificum, A. regale, A. splendidum, and A. warocqueanum, the Queen anthurium (some call it King anthurium) are classified under this section.
Anthurium clarinervium, commonly called “Hoja de Corazon, ” and A. leuconeurum may belong to a new section. Although both have the typical characteristics of Section Cardiolonchium, they do not cross with other members of this section.
Section Gymnopodium and Section
Chamaerepium. Each of these sections has only one species. The former is represented by A. gymnopus, a large climber with rounder, heart-shaped leaves that are slightly cupped and whose spadix is carried by a long stipe. The latter has A. radicans as representative. It is a small creeper with puckered, hear-shaped leaves and short, cylindrical spadix.
Section Leptanthurium. This also have one species, A gracile, that lives with ants in its natural habitat. Its unique characteristic is that the roots are white due to a layer of velamen, a covering of dead cells for root protection, which is common in epiphytic orchids.
Section Polyphyllium. A. clidemioides and A. flexile belong to this section. Their adventitious roots are formed at the internodes and they are the only anthuriums without cataphylls to protect the new leaves. Instead, a new leaf emerges from a sheath in the stalk of the previous leaf.
Section Xialophyllum. This is poorly known in horticulture. The anthuriums are characterized by erect or climbing stems with long internodes. They also have leaf blades that are typically longer than broad and only or rarely conspicuously lobed at the base. The pistils are not prominently exserted before anthesis or flower opening, about as long or no more than a few times longer than the stamens. A. angustispadix, A. davidsoniae, A. pallens, and other closely related species belong to a group with greenish inflorescences and fruits, and with thin, veiny, usually matter, often weakly puckered leaf blades. A. caucanum, A. mindensis, A. papayensis, and other closely related species, on one hand, belong to the group with leathery, usually semi-glossy to glossy leaf blade which are smooth or at least not markedly veiny or puckered.
Section Decurrentia. A. decurrens and A. pittieri are the only species classified under this section. They have short internodes and elongate, epunctate leaf blades. The spathe is conspicuously decurrent or extended down along the peduncle. The pistils are prominently exserted long before anthesis or flower opening and many times longer than stamens when they appear.
Section Urospadix. The anthuriums of this section have short stems with short internodes and generally epunctate leaf blades which are typically much longer than broad. The primary lateral veins are closely spaced, numerous, more uniform, and scarcely more prominent than the interprimary veins. The spathes are not decurrent. A. crassipes, A. imperiale and A. lucidum belong to this section.
Section Polyneurium. It is represented by A. caperatum, A. corrugatum, and A. pandufirome. They have relatively thin leaf blades which have many closely parallel primary lateral veins.
It is also important to note that the sectional grouping of different anthurium species is a guide for interspecific hybridization. Members of the same section interbreed easily and are also sexually compatible with species of sections having high affinity with it. Nevertheless, it is possible to produce wild crosses or hybrids between members of sections that are not closely related by using embryo rescue. With such tissues culture technique, I was successful in producing the first recorded intersectional hybrid of Pachyneurium and Cardiolonchium.
Asians could be the breeder and supplier of new varieties of the different anthurium sections in the near future. I hope a Filipino would be able to do it in the same way that outstanding hybrids of Aglaonema, Spathoglottis, and Mussaenda have been successfully bred and introduced to the world by our fellowmen.
Aside from the ornamental value of anthurium as a cutflower crop (A. andraeanum and its hybrids), cut foliage crop (A. affine and the other foliage-type species), potted plant (A. scherzerianum), hanging plant (A. gracile), landscaping plant (A. crystallinum, A. podophyllum, etc.) or as materials for making terrariums and dishgardens (A. radicans and A. amnicola), some species like A..ffexuosum and A. palmatum provide lengths of strong cordage for industrial use. The fiber from A. nymphaeifolium is ideal for guitar strings.
Meanwhile, the roots of A. scandens, a Pearl anthurium being used for basketmaking, are tough enough to be used as a wire and nails.
In western Cuba, A. gymnopus is called bejuco lombricero de cana or “worm vine of Sabal” because of its medicinal value. Extract from the plant that can be found only in the crown of a palm called Sabal maritima, where it grows as an epiphytic vine with thin and snake-like stems, kills intestinal parasites.