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Ceratopyxis Hook. f. Search in The Plant ListSearch in IPNISearch in Australian Plant Name IndexSearch in Index Nominum Genericorum (ING)Search in NYBG Virtual HerbariumSearch in JSTOR Plant ScienceSearch in SEINetSearch in African Plants Database at Geneva Botanical GardenAfrican Plants, Senckenberg Photo GallerySearch in Flora do Brasil 2020Search in Reflora - Virtual HerbariumSearch in Living Collections Decrease font Increase font Restore font
 

Published In: Hooker's Icones Plantarum 12: 24, tab. 1125. 1876. (Hooker's Icon. Pl.) Name publication detailView in BotanicusView in Biodiversity Heritage Library
 

Project Name Data (Last Modified On 8/17/2021)
Acceptance : Accepted
Note : Tribe Chiococceae
Project Data     (Last Modified On 8/17/2021)
Notes:

Ceratopyxis is a morphologically distinctive genus that is only known from the limestone "haystack hills" or mogote region of western Cuba. It is characterized by its shrub habit; foliage and inflorescences usually coated with apparently resinous exudate; opposite medium-sized leaves with a well developed submarginal vein and usually revolute margins; rather well developed, interpetiolar to shortly tubular, persistent stipules; inflorescences of unusual form; 5-merous flowers, white to cream or pale yellow corollas with a developed tube and markedly revolute lobes; well exserted anthers and stigmas; and small capsular fruits with one seed in each locule. The inflorescences are paired at a node well below the stem apex and sometimes below the leaves, and are born on well developed flexuous peduncles. The peduncles are articulated along their length with stipuliform and sometimes foliaceous bracts, and end in small cymes or subcapitate groups of flowers borne at several closely set nodes; the overall form of the inflorescences resembles some species of Acanthaceae. This species is restricted to a small geographic range in a distinctive habitat of Cuba, and is one of several morphologically enigmatic genera in this region. 

Hooker in the protologue and Borhidi et al. (2017) described the corolla lobes as valvate in bud, but on the flowers seen these are are thinly imbricated with an arrangement similar to that of several other Chiococceae genera (e.g., Acevedo-Rodríguez et al. 5729, Ekman 16595, both MO!). Hooker and Borhidi et al. also both described the stigmas as bilobed at the top, and this may be their condition but it not seen in this review, perhaps because the lobing is minute. It is not clear from the material seen if capsules open sequentially, or they open septicially and loculicidally simultaneously. The genus descrription presented by Borhidi et al. is esssentially a translation of selected parts of Hooker's protologue description. 

Ceratopyxis has not been studied in detail, beyond Cuban floristic treatments. It was included in the molecular analysis of Chiococceae by Paudyal et al. (2018), who found it deeply nested in the tribe and related there to some other endemic Antillean genera, Phialanthus, Schmidtottia, and Eosanthe. The place of publication of Ceratopyxis has is given incorrectly or incompletely in some sources. 

Author: C.M. Taylor.
The content of this web page was last revised on 17 August 2021.
Taylor web page: http://www.mobot.org/MOBOT/Research/curators/taylor.shtml

Distribution: Humid vegetation on limestone mogote hills, 200-350 m, western Cuba.
References:

 

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Shrubs and small trees, unarmed, terrestrial, without raphides in the tissues, sometimes with copious exudate covering vegetative and reproductive growth. Leaves opposite, petiolate, entire, with the higher-order venation not lineolate, without domatia, with well developed submarginal vein; stipules interpetiolar or shortly united around stem, triangular, keeled and cuspidate, erect and perhaps imbricated or valvate in bud, persistent after leaves fall. Inflorescences axillary at 1 node well below stem apex, spiciform with flowers in congested cymes or subcapitate groups, pedunculate, bracteate. Flowers bisexual, homostylous, apparently protandrous, perhaps fragrant and/or diurnal; hypanthium ellipsoid, flattened; calyx limb developed, deeply 5-lobed, without calycophylls; corolla at anthesis salverform, white to pale yellow or perhaps cream, somewhat small (0.6-0.8 cm), apparently glabrous inside, lobes 5, narrowly ligulate, in bud thinly imbricated with apparently two lobes internal two external, tightly reflexed and coiled at anthesis; stamens 5, inserted at base of corolla tube, filaments thickened and perhaps fused or coherent at base, anthers narrowly oblong, elongated, dorsifixed near base, dehiscent by linear slits, exserted, without appendages; ovary 2-locular, with ovules solitary and pendulous in each locule, stigma 1, slenderly cylindrical, with stigmatic lines twisted along sides, exserted. Fruit capsular, ellipsoid and flattened, loculidally and septicidally dehiscent from apex, septicidally fully deshicent into 2 valves 2, these partially loculicidal, rather small (ca. 5 mm long), chartaceous to woody, smooth, without lenticels, with calyx limb persistent; seeds 1 per locule, ellipsoid, compressed, small (ca. 2.5 mm), entire, densely verrucose to pilosulous.

 
 
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