Aloes and Lilies of Ethiopia and Eritrea

Description
Habitat and
distribution
Aloe percrassa
Description
ALOE
77
mm long) in comparison to smaller bracts (9.5–15 mm
long) in the latter.
Stemless, usually solitary. Leaves many, 43–52(–60) × 12–13.5(–
18.5) cm, gently recurved, slightly canaliculate, glossy olive­green,
with a horny layer along the margin which usually is contiguous
between the spines. Marginal spines 9–16 per 10 cm, 3 5 mm long,
brown. Inflorescence with 3–6(–8) ra cemes. Racemes subcapitate to
conical, 6–18 cm long, densely flowered. Bracts lanceolate, 20–30
× 6–7 cm, acute. Pedicels 12–18(–20+ in fruit) mm long. Perianth
cylindrical­trigonous, 26–32 mm long, 6–7 mm wide when pressed,
usually yellow, occa si onaly bright red; outer lobes free for 12–14
mm.
The species grows on steep bare mountain slopes between
2400 and 2460 m in Tigray and Welo floristic regions in
northern Ethiopia. It is so far not known anywhere else.
The main flowering period is in the dry season, from
February to April.
21. Aloe percrassa Todaro
The specific epithet ‘percrassa’ refers to the very (per­)
thick (­crassus) nature of the leaves and stems. The
species was described in 1875 based on a plant grown in
St. Petersburg (Leningrad) from seeds sent by Schimper
from Tigray floristic region in Ethiopia. The taxon has
also been known as A. abyssinica var. per cras sa Baker.
A. percrassa is in a group of aloes (A. debrana, A.
percrassa, A. rivae and A. trigonantha, numbers 21–
22 and 26–27) which is stemless (but some old plants
developing thick, prostrate stems), and which often has
secondarily branching inflorescences, with up to more
than 50 racemes. A. percrassa is distinguished from the
rest of the group by the large bracts, which are 10–16(–
20) mm long.
Succulent herb, suckering from base to form small groups,
commonly stemless but sometimes developing erect or decumbent
stem up to 80 cm long, 10–15 cm thick. Leaves crowded, 40–55 ×
13–15 cm or larger, glaucous­green or grey­green, often suffused
red, old leaves brown when drying. Marginal spines 6–16 per 10
cm, (2–)3–5 mm long, with pale pink to brown tips. Inflorescence
60–80 cm high with 5–12 racemes. Racemes cylindrical to conical,
6.5–25 cm long, with 2–5 flowers per cm. Bracts ovate acuminate,
(8–)10–16–20) × (2.5–)3–6 mm. Pedicels 11–17(–20) mm long.
Perianth cylindrical, 17–23 mm long, 4–6 mm wide pressed; outer
lobes free for 5–7 mm.