NUMBER 12 BIERNER: A NEW VARIETY OF HYMENOXYS AMBIGENS 31 HYMENOXYS AMBIGENS VAR. WAGNERI (ASTERACEAE:HELENIEAE:TETRANEURINAE), A NEW VARIETY IN HYMENOXYS SUBGENUS PLUMMERA FROM ARIZONA Mark W. Bierner School of Natural Resources and the Environment and School of Plant Biology, University of Arizona, Tucson, Arizona 85721 Plant Resources Center, 1 University Station F0404, The University of Texas, Austin, Texas 78712 [email protected] Abstract: Hymenoxys ambigens var. wagneri is a new variety endemic to the Dragoon Mountains of Cochise County, Arizona. Keywords: Asteraceae, Helenieae, Tetraneurinae, Hymenoxys, Plummera, Hymenoxys subg. Plummera, Hymenoxys ambigens. When Wagner et al. (1999) revisited compared to the previously described vari- Hymenoxys Cass. subg. Plummera (A. Gray) eties of Hymenoxys ambigens 1) tend to have Bierner, they mentioned a collection (Reich- larger heads, 2) have inner phyllaries that enbacher 1545) from Upper East Stronghold distinctly exceed the outer phyllaries (the Canyon in the Dragoon Mountains of Dragoon Mountain plants tend to have Cochise County, Arizona. They felt that it shorter outer phyllaries and longer inner was allied to H. ambigens (S. F. Blake) phyllaries, which explains this observation), Bierner var. floribunda (A. Gray) W. L. 3) have considerably more disc florets, and Wagner, but noted that it differed from the 4) have considerably wider pappus scales three known varieties of H. ambigens (vars. (compared to those of var. floribunda and ambigens, floribunda, and neomexicana W. L. especially var. neomexicana). They also have Wagner) in that it had considerably larger outer phyllaries that are fused to a lesser heads, inner involucral bracts that greatly extent than those of var. floribunda and var. exceeded the outer series of 5 bracts, a neomexicana, greater numbers of outer greater number of disc florets (18–20), and phyllaries, inner phyllaries, and ray florets ‘‘extremely wide’’ pappus scales. They sug- than var. ambigens and var. floribunda, outer gested that the collection might represent an and inner phyllaries of usually different undescribed species. morphology, longer and generally wider Examination of the Reichenbacher col- ray corollas, cypselae hairs that are distinctly lection and plants in situ (east side of the different in shape from those of var. Dragoon Mountains, Cochise County, Ar- floribunda and var. neomexicana, a greater izona – Bierner 2005-1 and Bierner 2005-2) number of pappus scales, especially com- lead me to concur with Wagner et al. (1999) pared to var. floribunda and var. neomex- that these plants are worthy of recognition as icana, and pappus scales of usually different a distinct taxon, albeit at the varietal level morphology. within Hymenoxys ambigens rather than at I have on occasion found functionally the specific level. bisexual disc florets in the Dragoon Moun- A comparison of characters of plants tain plants. One of the major criteria for from the east side of the Dragoon Moun- recognizing Hymenoxys subgenus Plummera tains with the varieties of Hymenoxys ambi- (5Plummera A. Gray) has been the presence gens is shown in Table 1. In accordance with of functionally staminate disc florets com- observations by Wagner et al. (1999), I agree pared to bisexual disc florets in other that the Dragoon Mountain plants when Hymenoxys taxa (e.g., Rydberg, 1915; Kear- LUNDELLIA 12:31–35. 2009 32 LUNDELLIA DECEMBER, 2009 ney and Peebles, 1942; Bierner, 2006). Blake am pleased to describe Hymenoxys ambigens (1929), when describing Plummera ambi- var. wagneri. gens, stated, ‘‘The presence of a well developed pappus in P. ambigens and the TAXONOMIC TREATMENT tendency toward fertility of the disc flowers … not only sharply differentiate the new Hymenoxys ambigens (S. F. Blake) Bierner plant from P. floribunda but tend to break var. wagneri Bierner, var. nov. down the gap between the section of Actinea often separated as a distinct genus Hyme- TYPE here designated: UNITED noxys and the hitherto well distinguished STATES. ARIZONA. Cochise Co.: Uncom- genus Plummera.’’ During a recent re- mon and widely scattered along trail and examination of P. ambigens var. ambigens ravine bottom on granite. Oak woodland; specimens at ARIZ, I could find no bisexual Upper East Stronghold Canyon along trail to disc florets in any of the mature heads, but I West Stronghold Canyon. SW 1/4 of NW 1/4 do not doubt that they occur infrequently. of S35 T17S R23E. Dragoon Mountains, Therefore, I believe it would be best to use a elevation 5900 feet, 10 Sep 1983, Reich- phrase such as ‘‘disc florets usually func- enbacher 1545 (HOLOTYPE: ARIZ!). tionally staminate’’ when distinguishing A Hymenoxys ambigens (S.F. Blake) Bierner subgenus Plummera from the other subgen- var. floribunda (A. Gray) W.L. Wagner bracteis era of Hymenoxys, although subgenus Plum- involucralibus externis 5; bracteis involucralibus mera is well separated by receptacle shape interna 5, 4–5 mm longis; floribus radii 5; (flat compared to hemispheric to globoid, floribus disci 16–20; et squamis pappi 5 differt. ovoid, or conic in the other subgenera) and the number of disc florets per head – 6–20 in PERENNIAL HERBS, 20–70 cm (polycarpic subgenus Plummera (with var. wagneri with sparingly branched woody caudices). included) compared to 25–400+ in the other STEMS 1–10, green throughout to purple- subgenera of Hymenoxys (Bierner, 2006). red-tinted proximally and green distally, Despite the occasional bisexual disc branched distally, sparsely to moderately floret, the Dragoon Mountain plants are, in pubescent, sparsely to moderately dotted my opinion, distinctly part of the subgenus with sessile glands. LEAVES: blades simple or Plummera clade; taxa in the other Hymenoxys pinnately or bipinnately lobed (lobes 3–17), subgenera invariably have very high percent- glabrous or sparsely pubescent, moderately ages of bisexual disc florets. Within subgenus to densely dotted with impressed glands; Plummera, the Dragoon Mountain plants fall basal leaves in a rosette, bases expanded and within my concept of Hymenoxys ambigens clasping stems, blades lobed (lobes 3–17); given similarities including branching pat- proximal cauline leaves lobed (lobes 5–15); tern, degree of leaf division, number of heads mid leaves lobed (lobes 5–13); distal leaves per plant, involucre shape, receptacle shape, simple or lobed (lobes 3–5). HEADS 50–300+ and degree of pubescence and glandularity. per plant, 5.5–833.5–5 mm, in paniculi- Within Hymenoxys ambigens, the Dragoon form to corymbiform arrays. PEDUNCLES 1– Mountain plants have a unique geographic 2.5 cm, expanded apically, glabrous or distribution (Fig. 1) and are consistently and sparsely pubescent, eglandular or sparsely substantially different from plants assigned to dotted with sessile glands. INVOLUCRES Hymenoxys ambigens vars. ambigens, flori- campanulate. PHYLLARIES in 2 morphologic bunda,andneomexicana (Table 1). series: outer phyllaries 5, basally connate 1/ In honor of Warren L. Wagner, the 2–2/3 their lengths, green to yellow-green leading expert on Hymenoxys subg. Plum- proximally and green distally, sometimes mera and the person who brought attention purple-red tinted on the margins, lanceolate to the unusual Reichenbacher collection, I to oblanceolate, 3.5–4.531.7–2 mm, strong- NUMBER 12 BIERNER: A NEW VARIETY OF TABLE 1. Comparison of plants from the east side of the Dragoon Mountains with the varieties of Hymenoxys ambigens. Dragoon Mts var. ambigens var. floribunda var. neomexicana Head size (H 3 D mm) 5.5–833.5–5 5–7.532.2–3.5 5–732.5–4 5–733–4.5 Outer phyllary number 5 4 3–4 5 Outer phyllary fusion 1/2–2/3 1/2–2/3 3/4 2/3–3/4 Outer phyllary size 3.5–4.531.7–2 4–531.5–2.2 4–631.2–3 4–4.531.3–2 (L 3 W mm) Outer phyllary apices Acute to acuminate Obtuse to acute Rounded to usually obtuse, Obtuse to acute to acuminate sometimes acute Inner phyllary number 5 4 3–4 5 Inner phyllary size 4–531.5–2 3.2–4.531.1–2 3.2–431.1–2 2.5–331–1.2 (L 3 W mm) Inner phyllary apices Acuminate to usually Acuminate to mucronate Rounded to obtuse to weakly Rounded to obtuse to weakly mucronate acute or mucronate acute or mucronate Ray floret number 5 4 3–4 4–5 Ray corolla size 5–7.532–4 4–5.532.3–4 4.5–632–2.5 3.4–4.231.7–2.2 (L 3 W mm) Disc floret number 16–20 7–11 6–13 8–15 Disc floret fertility Occasionally bisexual Functionally staminate Functionally staminate Functionally staminate Cypselae hairs Straight Straight to slightly wavy Strongly wavy Moderately wavy Pappus scale number 5 3–6 0 or 2–4 2–4 sometimes 0 on disc florets sometimes 0 on disc florets Pappus scale size 1–1.730.5–1 1.2–2.530.8–1 1–230.3–0.6 1.2–230.2–0.3 (L 3 W mm) Pappus scale shape Obovate or ovate to Lanceolate to narrowly Narrowly lanceolate Narrowly lanceolate HYMENOXYS AMBIGENS lanceolate lanceolate Pappus scale apices Rounded to obtuse to Acute to acuminate Acute to acuminate Obtuse to acute to acuminate acute to acuminate 33 34 LUNDELLIA DECEMBER, 2009 FIG. 1. Distribution of Hymenoxys ambigens varieties. ly keeled, apices acute to acuminate, abaxial abaxial faces glabrous, sparsely to moderate- faces glabrous or sparsely pubescent, sparsely ly dotted with sessile glands, adaxial faces to densely dotted with sessile and impressed glabrous and eglandular. DISC FLORETS 16– glands, adaxial faces glabrous and eglandu- 20, usually functionally staminate, occasion- lar; inner phyllaries 5, free, body yellow to ally bisexual; corollas differentiated proxi- yellow-green and scale-like, yellow to yel- mally into a yellow-brown tube 1/5–1/4 the low-green to green distally, obovate to total length, yellow distally, throats cylindric oblanceolate, 4–531.5–2 mm, distinctly sur- to cylindric campanulate, 2.8–3.330.4– passing the outer, weakly keeled, apices 0.6 mm, lobes 5, sparsely to moderately acuminate to usually mucronate, glabrous, pubescent, sparsely to moderately dotted eglandular.