DANIEL & TRIPP: LOUTERIDIUM : TAXONOMY, BIOLOGY, AND CONSERVATION 71 
10b. Rachis puberulent with (retrorse to) erect to flexuose to antrorse tri- 
chomes to 0.05 mm long; pedicels puberulent with erect to retrorse (to 
antrorse) trichomes to 0.05 mm long; abaxial surface of calyx pubescent 
like pedicels and sometimes with a few sparse glandular trichomes to 0.2 
mm long as well; capsule densely pubescent with glands (0.05-) 0.1-0.4 
mm long; leaf blades ovate-elliptic to obovate-elliptic to obovate; Pacific 
versant. L. purpusii 
1. Louteridium brevicalyxA. Richardson, Tulane Stud. Zoo. Bot. 17:66. 1972. Type. — MEX¬ 
ICO. Michoacan: Distr. Coalcoman, Aquila [ca. 18°35’49.39”N, 103°30’14.64”W], 200 m, 21-III- 
1941 (fir, frt), G. Hinton et al. 15825 (holotype: US!; isotype: NY!). 
Trees to 8 m tall, mostly epipetric. Older (woody) stems subquadrate to terete, irregularly fis¬ 
sured, sometimes ± scurfy, often lenticellate, lacking trichomes; younger (herbaceous) stems terete 
(when fresh), becoming flattened on drying, sparsely lenticellate, irregularly fissured, lacking 
trichomes. Leaves seasonally deciduous, clustered at shoot apex, petiolate, petioles to 90 mm long, 
sometimes tinged with pink or red, blades subsucculent, narrowly ovate to ovate to elliptic, 85-157 
mm long, 31-76 mm wide, 1.8-2.7 x longer than wide, acute to acuminate at apex, acute to atten¬ 
uate at base, surfaces glabrous (or rarely with very few scattered flexuose eglandular trichomes 
mostly on veins on abaxial surface, the trichomes especially evident on immature leaves), midvein 
somet im es pinkish to reddish purple (especially adaxially), margin entire. Inflorescence a terminal 
sessile or pedunculate thyrse to 38 cm long (including peduncle, if present, and excluding corol¬ 
las), peduncle (if present) pubescent with erect to flexuose glandular trichomes 0.05-0.7 mm long 
(glandular pubescent), rachis glandular pubescent and often with scattered erect to flexuose eglan¬ 
dular trichomes to 0.7 mm long as well; dichasia opposite or alternate, pedunculate, 1-many-flow¬ 
ered, to 120 mm long (excluding corollas), dichasial peduncles 15-60 mm long, pubescent like 
rachises. Bracts caducous (rarely present), lanceolate to lance-ovate, 6.5-7.5 mm long, 2.5-2.8 mm 
wide, abaxially pubescent like rachis (except sometimes with more eglandular trichomes). Bracte- 
oles and secondary bracteoles caducous, lance-subulate to linear to ovate-elliptic, 2-7 mm long, 
0.9-2 mm wide, abaxially pubescent like rachis or with more eglandular trichomes. Flowers pedi¬ 
cellate, pedicels 25-50 mm long, glandular pubescent. Calyx 10-16 mm long, lobes fused at base 
for 1.5-3 mm, subhomomorphic to subheteromorphic, membranaceous, lanceolate to ovate, 
7.5-12 mm long, 3-7 mm wide, subequal or with posterior lobe either slightly larger or smaller 
than lateral lobes, acute at apex, abaxially pubescent with erect to flexuose glandular and eglandu¬ 
lar trichomes 0.05-0.3 mm long, posterior lobe subplanar to subconduplicate. Corollas greenish, 
35-65 mm long, externally pubescent with erect to flexuose glandular and eglandular trichomes 
0.05-0.3 mm long, tube 25-30 mm long, narrow proximal portion 7-12 mm long, 7-11 mm in 
diameter near midpoint, throat 15-25 mm long, 26-30 mm in diameter at mouth, lobes spreading 
to recoiled, ovate to subcircular, 15-24 mm long, 16-24 mm wide, rounded and emarginate at apex. 
Stamens 4, 65-80 mm long, filaments distally glabrous, pubescent with eglandular trichomes near 
base, thecae 8-11 mm long; staminode 0. Style 75-77 mm long, glabrous distally, pubescent near 
base with eglandular trichomes, stigma subequally 2-lobed and ± funnelform, lobes elliptic to 
subspheric, 2-3 mm long, 1.5-3 mm wide. Capsules 32-42 mm long, 6-9.5 mm in diameter, 
pubescent with erect to flexuose eglandular and subsessile to stipitate glandular trichomes less than 
0.05-0.4 mm long, stipe 2-5.2 mm long. Seeds 16-24 per capsule, 5.5-7 mm long, 4.5-6 mm wide, 
surfaces smooth. 
Phenology. — Flowering: March; fruiting: March. Field observations on Daniel & Stein- 
