Orchid Information - Genus Mediocalcar

Few genera in New Guinea are as distinctive as Mediocalcar, with its brightly coloured, shiny, urn-shaped flowers, which have a most un-orchid-like appearance. They are almost certainly pollinated by birds, but this has yet to be confirmed by observations in the field. The statement in Prigeon et al. (2005: 564) that flowers of Mediocalcar are thought to mimic those of Vaccinium and other Ericaceae is disproved by the fact that the flowers of Mediocalcar contain nectar and that New Guinea Vacciniums do not have such brightly coloured flowers as Mediocalcar. In other words, Mediocalcar flowers offer an award and they have no model, so the term 'mimic' seems ill-chosen.

The nearest relative is undoubtedly Epiblastus, a genus with superficially similar flowers, in which the sepals are not connate, however (Schuiteman, 1997). This sister group relationship was recently confirmed by molecular work of Ng Yan Peng (see cladogram in Pridgeon et al. 2005: 531).

Schlechter and J. J. Smith recognised three, respectively two sections within the genus, but these do not correspond to natural groups (Schuiteman, 1997).

A key to the species of Mediocalcar is here included in the Text Key module (click on the Text Key icon in the Navigator window, click on Find at the bottom of the text Key window and type Mediocalcar).

Most species are easy to cultivate under permanently cool and humid conditions.


KEY TO THE SPECIES AND SUBSPECIES OF THE GENUS MEDIOCALCAR (after Schuiteman, 1997)

1a. Base of pseudobulb elongated, enveloping the rhizome (fig. A). New shoot usually arising from near the middle to near the top of the pseudobulb. Inflorescences synanthous or heteranthous == 2
1b. Base of pseudobulb not elongated or, if elongated, base saddle-shaped, clasping but not enveloping the rhizome (fig. B). New shoot usually arising from the base of the pseudobulb. Inflorescences synanthous only (possibly heteranthous in Mediocalcar congestum; in that species the base of the pseudobulb is not elongated) == 11

2a. Spur (almost) extending to the base of the lip (fig. A) == 3
2b. Spur at most extending to about halfway the claw of the lip (fig. B) (When in doubt try lead a first. == 7

3a. Pseudobulbs predominantly 3- or 4-leaved == 4
3b. Pseudobulbs 1- or 2-leaved == 5

4a. Leaves 2 - 4 mm wide == Mediocalcar decoratum
4b. Leaves 4 - 10 mm wide, with at least some leaves more than 5 mm wide == Mediocalcar umboiense

5a. Leaves subterete == Mediocalcar subteres
5b. Leaves dorso-ventrally flattened == 6

6a. Inflorescences in pairs, synanthous only. Free part of pseudobulb 1-3.5 cm long == Mediocalcar arfakense
6b. Inflorescences either solitary or, if in pairs, both heteranthous and synanthous. Free part of pseudobulb 0.5 - 1 cm long == Mediocalcar versteegii

7a. Leaves (broadly) elliptic, less than 2 cm long. Flowers narrowly urceolate == Mediocalcar pygmaeum
7b. Leaves when elliptic more than 2.5 cm long or leaves linear. Flowers narrowly urceolate to urceolate-globose == 8

8a. Flowers with greenish or yellowish tips, or, if flowers white-tipped, at least some pseudobulbs more than 4 mm thick == 9
8b. Flowers with white tips. Pseudobulbs less than 4 mm thick == Mediocalcar bifolium

9a. Pseudobulbs 2- or 3-leaved. Leaves elliptic, margins irregular. Inflorescences solitary or in pairs, synanthous only. Flowers narrowly urceolate. Blade of lip ovate when flattened, claw sigmoid == Mediocalcar stevenscoodei
9b. Pseudobulbs 1- or 2-leaved. Leaves elliptic to linear, margins entire. Inflorescences solitary, synanthous or heteranthous. Flowers urceolate-globose. Blade of lip broadly ovate to subcordate when flattened, claw almost straight == 10

10a. Pseudobulbs 2-leaved (some 1-leaved shoots may be present). Leaves 2.5 - 10 cm long, broadly rounded at the apex. Inflorescences synanthous == Mediocalcar agathodaemonis
10b. Pseudobulbs 1-leaved (some 2-leaved shoots may be present). Leaves 5 - 13.5 cm long, gradually tapering to the apex. Inflorescences synanthous or heteranthous == Mediocalcar versteegii == 11

11a. Spur about as long as the claw of the lip == 12
11b. Spur at most about half as long as the claw of the lip. Flowers with == Mediocalcar versteegii subsp. intermedium

12a. Inflorescences solitary. Pseudobulbs 1.5-5 cm long == Mediocalcar versteegii subsp. versteegii
12b. Inflorescences mostly in pairs. Pseudobulbs 0.8-1.4 cm long == Mediocalcar versteegii subsp. amphigeneum

13a. Spur (almost) extending to the base of the lip (fig. A) == 14
13b. Spur at most extending to about halfway the claw of the lip (fig. B). (When in doubt try lead a first) == 16

14a. Pseudobulbs terete. Inflorescences solitary == Mediocalcar uniflorum
14b. Pseudobulbs (broadly) conical. Inflorescences frequently in pairs == Mediocalcar paradoxum == 15

15a. Cataphylls patent, laterally compressed, subfalcate. Pseudobulbs usually subglobose, often dorso-ventrally compressed and 2-angled. Leaves broadly elliptic to suborbicular, usually distinctly petiolate == Mediocalcar paradoxum subsp. latifolium
15b. Cataphylls patent, laterally compressed, subfalcate. Pseudobulbs usually subglobose, often dorso-ventrally compressed and 2-angled. Leaves broadly elliptic to suborbicular, usually distinctly petiolate == Mediocalcar paradoxum subsp. robustum

16a. Pseudobulbs 1-leaved, close together (distance between pseudobulbs less than their height). Rhizome rather short to very short == 17
16b. Pseudobulbs 1- to 3-leaved, widely spaced on a long creeping rhizome (except sometimes in Mediocalcar pygmaeum, which always has 2- or 3-leaved pseudobulbs) == 18

17a. Leaves elliptic (index 2 - 3), less than 3 cm long == Mediocalcar bulbophylloides
17b. Leaves linear-lanceolate (index 5.5 - 19), more than 4 cm long == Mediocalcar congestum

158. Pseudobulbs (broadly) conical, 1-leaved. Leaves with entire margins, obtuse to subacute == Mediocalcar paradoxum
18b. Pseudobulbs narrowly conical to cylindrical, 1- to 3-leaved. Leaves with crenulate margins at least near the apex, obtuse to acuminate, but acute to acuminate when pseudobulbs 1-leaved == 19

19. Base of pseudobulbs elongated, free part at most 0.5 cm long, 2- or 3-leaved. Leaves less than 2 cm long == Mediocalcar pygmaeum
19b. Base of pseudobulbs not elongated, free part at least 1 cm long, 1- or 2-leaved. Leaves (usually) more than 2 cm long == 20

20a. Pseudobulbs 2-leaved. Leaves elliptic, petiolate, 2-8 cm long. Spur shallowly cucullate. Column-foot incurved == Mediocalcar geniculatum
20b. Pseudobulbs 1- or 2-leaved. Leaves lanceolate, subsessile, 4-19 cm long. Spur saccate. Column-foot not incurved == Mediocalcar crenulatum


Genus Mediocalcar contains 17 species and 5 subspecies; all species and 4 varieties occur in New Guinea:

Mediocalcar agathodaemonis
Mediocalcar arfakense
Mediocalcar bifolium
Mediocalcar brachygenium
Mediocalcar bulbophylloides
Mediocalcar congestum
Mediocalcar crenulatum
Mediocalcar decoratum
Mediocalcar geniculatum
Mediocalcar papuanum
Mediocalcar paradoxum subsp. latifolium
Mediocalcar paradoxum subsp. robustum
Mediocalcar pygmaeum
Mediocalcar stevenscoodei
Mediocalcar subteres
Mediocalcar umboiense
Mediocalcar uniflorum
Mediocalcar versteegii
Mediocalcar versteegii subsp. amphigeneum
Mediocalcar versteegii subsp. intermedium