Studies in Neotropical Apocynaceae LIV: a synopsis of Asketanthera
Author
Morales, J. Francisco
text
Candollea
2018
2018-03-27
73
1
7
17
journal article
3533
10.15553/c2018v731a2
ea73ea53-7e6c-4e4e-8260-7da383dffc67
2235-3658
5683677
3.
Asketanthera longiflora
Woodson
in Ann.
Missouri
Bot. Gard. 19: 47. 1932 (
Fig. 3
,
4
).
Ξ
Echites longiflorus
Ekman & Helwig
in Ark. Bot. 22A(10): 45. 1929 [non
E. longiflorus
Desf.
].
Ξ
Asketanthera ekmaniana
Woodson, Ann.
Missouri
Bot. Gard. 23: 267. 1936 [nom. illeg. superfl.].
Lectotypus
(designated here):
DOMINICAN REPUBLIC
.
Prov. Barahona
:
Santo Domingo
,
cordillera de Bahoruco, sierra de los Cornincuios
,
between Beueve and Gros Figuier, near Vrickets
,
28.VIII.1926
, fl.,
Ekman
6762
(
S
[
S04-1837
]!; isolecto
-
:
JE
[fragment]!).
Branchlets
sparsely puberulent to glabrate; interpetiolar colleters up to
1.4 mm
long.
Petioles
4-8 mm
long; leaf blades 7.5-13.1 ×
3-6.8 cm
, ovate, ovate-elliptic to elliptic, the apex acuminate, the base obtuse, glabrous on the adaxial surface, sparsely puberulent to glabrate on the abaxial surface, secondary veins impressed on both surfaces.
Inflorescence
very sparsely puberulent, 2-4-flowered, peduncle
10-28 mm
long, pedicels 10-22(-25) mm long, bracts 9-20 ×
1.5-4 mm
, linearelliptic, linear-ovate, narrowly ovate to narrowly elliptic; sepals 16-24 ×
5-7 mm
, narrowly ovate to ovate-elliptic, the apex shortly acuminate, glabrate externally, the colleter irregularly erose at the apex.
Corolla
green, inconspicuously puberulent to glabrate, the indument more dense in floral buds, tube 63-80 ×
3.5-7 mm
, inflated around the stamens,
6-7 mm
diam. at the orifice; lobes 60-90 ×
22-25 mm
, obliquely elliptic; stamens inserted in the proximal half of the corolla tube, anthers
11-14 mm
long, the auricles obtuse, style-head
3-4 mm
long; ovary
3-4 mm
long, glabrous; nectaries c. half of the ovary length, irregularly lobed.
Follicles
18.5-20 cm
×
3.5-5 mm
, free, sparsely puberulent to glabrate, continuous; seeds unknown.
Distribution, habitat and phenology
. – Endemic to Hispaniola (
Dominican Republic
and
Haiti
), growing in wet forest over limestone hills from
1000-1300 m
. Flowering in August and September. Fruits have been reported in November.
Conservation status
. – This species is known from only four localities in Hispaniola with an EOO of
865 km
2
and an AOO of
16 km
2
, from regions with highly disturbed and fragmented forest remnants. Three of the specimens were collected more than 90 years ago, but future fieldwork could probably reveal additional populations.
Asketanthera longiflora
is provisionally assessed as “Endangered” [ENB1ab(iv) + B2ab(iii,iv)] following IUCN Red List Categories and Criteria (
IUCN, 2012
).
Notes
. –
Asketanthera longiflora
is easily recognized by its 2-4-flowered inflorescences and the corolla tube
63-80 mm
length.
WOODSON (1936)
described 2-8-flowered inflorescences, but in all the specimens examined (included those examined by Woodson) the inflorescence has up to 4 flowers. The duplicate of
Ekman 6762
at S is designated here as the
lectotype
. One duplicate is deposited at JE, but it is a fragment, whereas a second duplicate at B was destroyed in 1943.
Fig. 3. –
Distribution map of the four accepted species in
Asketanthera
Woodson.
Specimens examined. –
HAITI
. Dept. Sud:
eastern La Hotte, Chapelle Mont Carmel,
8.XI.1924
, fr.,
Ekman 2426
(
S
); massif de la Hotte, eastern group, St. Grave, near Chap St. Mickel, steeps, limestone hillside,
4.VIII.1926
, fl.,
Ekman 6598
(
S
).
DOMINICAN REPUBLIC
. Prov.
Pedernales
:
50 km
de la Compañía de Exploración Alcoa, Puerto Cabo Rojo, camino a las Mercedes and Las Abejas, área llamada Las Abejas,
15.IX.1981
, fl.,
Zanoni & Mejía 16561
(CR, MO, NY).