Anthurium antioquiense Engl., A. amnicola Dressler and others once believed to be
members of of section Porphyrochitonium have proven to be members of sect. Calomystrium
but warrant recognition as a distinct series, ser. Rupicola Croat (Croat & Whitehill, in prep.).
This small group of riparian species differ in having more or less lanceolate leaves. Also
included in this series are A. antrophyoides Killip, A. sytsmae Croat, A. rupicola Croat and two
undescribed species from South America, A. werfii and A. palacioanum .
XV. BELOLONCHIUM Schott emend Engl. (Fig. 35-39)
This section is the most poorly known of all sections included in Engler's revision of
Anthurium and would appear to be a "dumping ground" for all cordate species not clearly
assigned to other groups with cordate leaves such as sections Cardiolonchium and Calomystrium .
There are at least two groups of seemingly related cordate species currently placed here
and the section may ultimately have to be divided into several distinct sections. In one group the
leaves are relatively coriaceous and dry brown. Examples of this group are A. bogotense Schott,
A. brownii Masters, A. concinnatum Schott, A. gualeanum Engl. (Fig. 35), A. incurvatum Engl.,
A. rigidifolium Engl. and A. variegatum Sodiro (Fig. 36). Quite a number of the species in this
group occur at relatively high elevations and bear more or less hooded spathes (Fig. 37-39).
These species fit Schott's original circumscription of the section. Still another group has
thinner leaf blades which dry green. These include A. dolichostachyum Sodiro, A. lancetillense
Croat, A. ovandense Matuda and A. umbrosum Liebm.
Most species in the section Belolonchium have 2N = 30 chromosomes though one species
(A. patulum Sodiro) was reported as having 28 + 1f chromosome (Sharma & Bhattacharya,
1976) in the diploid condition. Still another species believed to be in this section (A. supianum
Engl.) is reported to have ca. 90 chromosomes (Sheffer & Kamemoto, 1976).
Two species reported for this section by Sheffer & Croat (1983) were erroneously
placed in this section. Anthurium cerrocampanense Croat with 2N = 30 + 2B chromosomes is
best placed in section Cardiolonchium while A. signatum C. Koch & Mathieu with 2N = 34 is best
placed in section Semaeophyllium .
Little documented data is available about hybridization within the section. Based on fruit
set only, intrasectional pollinations and intersectional pollinations between Belolonchium and
Cardiolonchium or Calomystrium are in general successful.
XVI. SEMAEOPHYLLIUM Schott (Fig. 40-42)
This section as treated by Schott contained only the deeply 3-lobed species and would
have appeared to be a relatively natural group. Engler's realignment, based on the shape of the
inflorescence, is, in my opinion, an unnatural one. The section has species with generally short
stems with short internodes. The blades are deeply 3-lobed but entire, not divided into leaflets.
Examples include A. falcatum Sodiro, A. furcatum Sodiro (Fig. 40), A. garagaranum Standley,
A. grexavium Madison, A. insigne Masters, A. rimbachii Sodiro, A. signatum C. Koch & Bouché,
A. truncicolum Engl. (Fig. 41), A. tilaranense Standley, A. tridigitatum Engl. and A. subsignatum
Schott (Fig. 42).