ACORUS/ACORACEAE 1077 CLASS MONOCOTYLEDONAE Plants usually herbaceous—in other words, lacking regular secondary thickening (except Palmaceae, Smilacaceae, most Agavaceae, and a few Poaceae); seedlings usually with 1 seed leaf or cotyledon; stems or branches elongating by apical growth and also by growth of basal por- tion of internodes; leaves when present alternate, whorled, basal, or rarely opposite, elongating by basal growth (readily seen on spring-flowering bulbs whose leaf-tips have been frozen back); leaf blades usually with parallel or concentrically curved veins, these unbranched or with inconspicuous, short, transverse connectives (leaves net-veined or with prominent midrib and spreading side-veins parallel with each other in Alismataceae, Araceae, Smilacaceae, Marantaceae, and some Orchidaceae); perianth with dissimilar inner and outer whorls (petals and sepals), or all parts about alike (tepals), the parianth parts separate or united, commonly in 3s, less often in 2s, rarely in 5s, or perianth of scales or bristles, or entirely absent. AWorldwide, the Monocotyledonae is a group composed of ca. 55,800 species in 2,652 genera arranged in 84 families (Mabberley 1997); 25 of these families occur in nc TX. The monocots appear to be a well-supported monophyletic group derived from within the monosulcate Magnoliidae group of dicots (Chase et al. 1993; Duvall et al. 1993; Qiu et al. 1993). From the cla- distic standpoint, the dicots are therefore paraphyletic and thus inappropriate for formal recog- nition (see explantion and Fig. 41 in Apendix 6). Within the monocots, Acorus appears to be the sister group to all other monocots, with the Alismataceae (and Potamogeton) being the next most basal group (Duvall et al. 1993). REFERENCES: Cronquist 1981, 1988, 1993; Dahlgren et al. 1985; Thorne 1992; Chase et al. 1993; Clark et al. 1993; Duvall et al. 1993; Qiu et al. 1993; Reveal 1993a, 1993b; Takhtajan 1997. ACORACEAE SWEETFLAG OR CALAMUS FAMILY AAcorus has traditionally been placed in the Araceae (e.g., Dahlgren et al. 1985) despite many characters unusual for an aroid. Grayum (1987) gave extensive reasons why the genus should be placed in its own family. The Acoraceae, thus circumscribed, is a very small, Old World and North American family of 2 species (3 if Gymnostachys is included). Using cpDNA restriction site analysis, a clade containing Acorus and the somewhat similar Gymnostachys (also tradi- tionally placed in the Araceae) was resolved as a sister group of all other monocots (Davis 1995). An anaylsis by Duvall et al. (1993) also pointed to Acorus as the most basal living lineage of monocotyledons and a more recent molecular study by Soltis et al. (1997) again suggested that Acorus is anomalous among monocots. These results all support the recognition of the Acoraceae as separate from the Araceae and suggest further study is needed to determine its phylogenetic position. (subclass Arecidae) FAMILY RECOGNITION IN THE FIELD: the only member of this family in nc TX is an aromatic herb with sword-like leaves roughly 1 m long and a cylindrical, finger-like spadix diverging laterally from an elongate, spathe-like scape. REFERENCES: Wilson 1960a; Grayum 1987; Duvall et al. 1993; Davis 1995; Soltis et al. 1997. ACORUS SWEETFLAG, CALAMUS AA genus of 2 species with iris-like or grass-like leaves; sometimes cultivated for fragrant oils in rhizomes. (Latin name for an aromatic plant or possibly Latin: acorus, without pupil, the name used by Dioscorides for an iris used in treating cataracts) REFERENCES: Buell 1935; Harper 1936. Acorus calamus L., (ancient name for a reed). DRUG SWEETFLAG, SWEETFLAG, CALAMUS. Aro- matic, rhizomatous (thick) perennial herb with erect, linear, sword-shaped, parallel-veined 1078 AGAVACEAE leaves 0.9Ð1.2 m long, 5Ð25 mm wide; inflorescence an exposed cylindrical spadix, 4Ð9 cm long, diverging laterally from an elongate, leaf-like, spathe-like scape; flowers perfect, covering the spadix; perianth of 6 short segments; stamens 6; carpels 2Ð3; fruit a few-seeded berry. Wet ground or shallow water; Dallas Co., also Denton and Tarrant cos. (Mahler 1988). MayÐJun. The geographic origin of Acorus has been somewhat confused. The genus is apparently introduced in TX, but was described as native in 1833 (Mahler 1988); Harper (1936) questioned whether Acorus is native to the U.S.; Buell (1935), however, concluded that the genus is native to the inte- rior of North America. According to J. Kartesz (pers. comm.), TX plants are introduced from the Old World, with A. americanus (Raf.) Raf. extending no further s in the Great Plains than Ne- braska and Iowa. Jones et al. (1997) treated TX material as A. americanus. This species has been used medicinally since the time of Hippocrates; it was also known from Tutankhamun’s tomb; it is used religiously as “oil of holy ointment” for anointing sacred items and referred to in Exo- dus as SWEET CALAMUS; in Sumatra it is hung up at night to keep evil spirits from children; it is also apparently effective as an insecticide (Mabberley 1997). Duke (1985) referenced sources in- dicating that oil of calamus is carcinogenic, probably due to the presence of asarone (an allylbenzene) or safrole; McGuffin et al. (1997) indicated asarone is potentially hepatocarcino- genic and can cause chromosome damage in human lymphocytes. 9 I AGAVACEAE YUCCA, CENTURY-PLANT OR AGAVE FAMILY Herbaceous or woody, usually xerophytic perennials from a pithy corm or soft-woody root; leaves usually basal or bunched, narrow, flat to concave or thickened, ± fleshy or leathery, with widened, clasping base; flowering stems with alternate leafy bracts; flowers in racemes or panicles; tepals 6, in 1 or 2 rows; stamens 6; pistil 1; ovary superior or inferior; fruit a capsule. AA medium-sized family (550 species in 18 genera—B. Hess, pers. comm.) mainly of arid or semi-arid tropics and subtropics, especially in the Americas; its taxa have sometimes been treated as Amaryllidaceae, Asteliaceae, Dracaenaceae, Liliaceae, or Nolinaceae; some authorities (e.g., Heywood 1993) have suggested they may be more closely related to taxa in the Liliaceae than to each other. Molecular studies (Bogler & Simpson 1995, 1996) indicated the family as treated here is probably not monophyletic and supported the recognition of Nolinaceae and a more narrowly circumscribed Agavaceae. Ornamentals include species of Agave, Dracaena , Sansevieria (MOTHER-IN-LAW’S-TONGUE), and Yucca. Family name from Agave, AGAVE, MAGUEY, or CENTURY-PLANT, a genus of 100+ species native from the s United States to tropical South America. Agave species are the source of sisal hemp and pulque, a Mexican “beer” distilled to produce mescal and tequila. (Greek: agave, noble or admirable, in reference to the handsome appearance when in flower) (subclass Liliidae) FAMILY RECOGNITION IN THE FIELD: usually xerophytic, typically robust perennials with often elongate narrow leaves usually basal or crowded near base of stem (or at stem apex in large tree- like YUCCAS) and sometimes sharp-pointed; inflorescence a raceme or panicle; fruit a capsule. REFERENCES: Dahlgren et al. 1985; Bogler & Simpson 1995, 1996. 1. Flowers rosy red or salmon-colored; leaves conspicuously revolute (inrolled) upon drying (the margins nearly touching) Hesperaloee 1. Flowers white to greenish or yellowish (can be reddish brown towards tips); leaves not revolute (can be v-shaped in Manfreda). 2. Ovary superior; leaves usually 30 cm long or more OR if shorter with a hard spiny tip, not succulent (but can be thick), often < 4(–8) cm wide (but 3–8 cm wide in the large tree-like YUCCAS). HESPERALOE/AGAVACEAE 1079 3. Flowers 13–78+ mm long or broad; leaves 8–80 mm wide; capsules large (much > 1 cm long), the seeds numerous in each cell Yuccaa 3. Flowers 2.5–6 mm long or broad; leaves 2–12 mm wide; capsules small (< 1 cm long), the seeds solitary in each cell Nolina 2. Ovary inferior; leaves 10–30 cm long, without a hard spiny tip, succulent, 1–7(–10) cm wide Manfreda HESPERALOE AA genus of 5 species native to sw North America (Starr 1997). (Greek: hesperos, western or evening, and the genus name Aloe) REFERENCES: Trelease 1902; Starr 1995, 1997; Pellmyr & Augenstein 1997. Hesperaloe parviflora (Torr.) J.M. Coult., (small-flowered), RED-FLOWERED-YUCCA, RED HESPERALOE. Leaves numerous, crowded at base of plant, linear, to 1.2 m long; flowering stem to 2.5 m tall, usually few-branched; pedicels to 35 mm long; flowers tubular to oblong-campanu- late, 25Ð35 mm long; stamens shorter than the corolla; style slightly to much exserted; capsules to 3 cm or more long. Rocky slopes, open areas; Mills Co. in sw part of Lampasas Cut Plain, also across the Colorado River in San Saba Co., also spreading from cultivation in Brown Co. (Stanford 1976) and reported by Starr (1997) from Collin Co. [escaped?]; otherwise mostly much further w in sw TX. MarÐSep. [Yucca parviflora Torr.] The striking flower color immediately dis- tinguishes this species from all other nc TX Agavaceae; it is widely used as an ornamental. Pol- lination is reported to be by hummingbirds as well as bees (Starr 1995); experiments by Pellmyr and Augenstein (1997) showed the species to be self-incompatible and pollinated by black- chinned hummingbirds (Archilochus alexandri). m/92 MANFREDA FALSE ALOE, AMERICAN-ALOE AA genus of 25 species ranging from the se United States to Honduras and El Salvador (B. Hess, pers. comm.). The species have been variously recognized in Agave, Manfreda, and Polianthes. (Named for Manfred, an ancient Italian writer) REFERENCES: Shinners 1951f, 1966a; Verhoek-Williams 1975. Manfreda virginica (L.) Rose, (of Virginia). Glabrous perennial; leaves mostly in a basal rosette, soft, thick-herbaceous, somewhat fleshy; flowers in a spike-like raceme; perianth tubular-funnel- form; anthers linear, versatile (= attached near middle); capsules 3-celled, oblong to globose, 14Ð 20 mm long, with numerous flattened seeds.