Home Rubiaceae
Home
Name Search
Generic List
Nomenclature Notes on Rubiaceae
Rubiaceae Morphology
Discussion and Comments
Pittoniotis Griseb. 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: Bonplandia 6(1): 8. 1858. (15 Jan 1858) (Bonplandia (Hannover)) Name publication detailView in Biodiversity Heritage Library
 

Project Name Data (Last Modified On 6/25/2021)
Acceptance : Accepted
Note : Tribe Guettardeae
Project Data     (Last Modified On 6/25/2021)
Notes:

Pittoniotis is characterized by its habit as a large tree; paired leaves with lineolate higher-order venation; interpetiolar triangular stipules that often persist with the leaves and surround a dense ring of sericeous trichomes inserted on the stem; densely flowered cymose inflorescences that are axillary or produced on short axillary stems; small white to yellow corollas with the 5 lobes longer than the narrow corolla tube and imbricated in bud; and small red drupaceous fruits with a single 2-locular pyrene, and 1 seed in each locule. This genus comprised one species from the Caribbean basin until recently, when a second species from the Andes of Ecuador and Peru was described. Pittoniotis trichantha is commonly collected. 

Pittoniotis trichantha is deciduous, and produces its flowers with the new leaves. The branching of this species has stems that elongate regularly from the terminal buds, while Pittoniotis rotata has markedly sylleptic branching. The plants are rather densely strigose to strigillose on vegetative and reproductive structures. The subrotate corolla form of both species of Pittoniotis, with the lobes longer than the tubular portion, is distinctive within the Neotropical species of Guettardeae. The numerous flowers of Pittoniotis trichantha apparently flower generally together, and produce a strong fragrance. Lorence et al. (2012) described the corollas of Pittoniotis trichantha as glabrous internally, but these are at least sometimes densely strigose in the tube and densely villosulous adaxally on the lobes. The infructescence axes elongate markedly and become recurved and the fruits develop, so these fruits are well separated from each other for presentation to dispersers.

Pittoniotis trichantha has sometimes been treated as a monotypic genus, but also sometimes included in a broadened circumscription of Antirhea. Chaw & Darwin (1992) clarified the circumscription and characters of Antirhea as  Paleotropical genus. The systematics of the related Neotropical Guettardeae with drupaceous fruits is not yet well understood, but is clearly complex. Achille et al. (2006) presented a molecular overview of the group with a focus on Guettarda, and found Pittoniotis placed as basal to the remaining genera of their ingroup with poor support. No other studies seem to have included this genus. Pittoniotis has been separated by recent authors (Taylor & Gereau 2010, and references cited there). The relation ship of the Caribbean and Andean species will deserve re-evaluation when feasible. 

Author: C.M. Taylor
The content of this web page was last revised on 25 June 2021.
Taylor web page: http://www.mobot.org/MOBOT/Research/curators/taylor.shtml

Distribution: Southern and western Caribbean basin, on coasts from Guatemala to Venezuela, and cloud forest in Andes of Ecuador and Peru.
References:

 

Export To PDF Export To Word

Trees to 20--30 m, unarmed, terrestrial, without raphides in the tissues, at least sometimes deciduous and flowering with the new leaves. Leaves opposite, petiolate, entire, with higher-order venation lineolate, with pubescent domatia; stipules interpetiolar, triangular, acuminate, apparently valvate in bud, caducous, adaxially with dense line of sericeous pubescence. Inflorescences axillary and ramiflorous, cymose-corymbiform, several- to multiflowered, pedunculate, with axes scorpioid, bracts reduced to developed. Flowers subsessile, ebracteolate, bisexual, homostylous, protoandrous, strongly fragrant, diurnal; hypanthium ellipsoid; calyx limb developed, (4)5-lobed, without calycophylls; corolla slenderly salverform, small (2.5--5 mm long), white to yellow, internally strigose or perhaps glabrous in tube and hirtellous on lobes, lobes 5, narrowly triangular, equal to or longer than tube, imbricated in bud, without appendages; stamens 5, inserted at top of corolla tube, anthers narrowly oblong, dorsifixed near base, exserted, opening by linear slits, without appendage; ovary 2-locular, ovules 1 per locule, pendulous from apical placentas; stigmas 2, narrowly ellipsoid and stout, exserted. Fruits drupaceous, obovoid-ellipsoid, juicy, red, small (5--6 mm long) to medium-sized (20--25 mm long), with calyx limb persistent; pyrene 1, 2 locular, obovoid-ellipsoid, bony; seeds cylindrical, smooth.

 

Export To PDF Export To Word Export To SDD
Switch to indented key format
1 Inflorescence axes branched to 2-3 orders; corolla subrotate, with the tube ca. 1 mm long and the lobes ca. 4 mm long; fruits 20-25 x 8-10 mm; cloud forests of Andes. Pittoniotis rotata
+ Inflorescence axes branched to 3-5 orders; corollas subrotate to shortly tubular, with the tube 1.5-2 mm long and the lobes 2-3 mm long; fruits 5-6 x 2-3.5 mm; seasonal and subhumid vegetation of southern and western Caribbean basin. Pittoniotis trichantha
 

Export To PDF Export To Word

Key to Species of Pittoniotis

1. Inflorescence axes branched to 2-3 orders; corolla subrotate, with the tube ca. 1 mm long and the lobes ca. 4 mm long; fruits 20-25 x 8-10 mm; cloud forests of Andes.....Pittoniotis rotata

1. Inflorescence axes branched to 3-5 orders; corollas subrotate to shortly tubular, with the tube 1.5-2 mm long and the lobes 2-3 mm long; fruits 5-6 x 2-3.5 mm; seasonal and subhumid vegetation of southern and western Caribbean basin......Pittoniotis trichantha

 
 
© 2024 Missouri Botanical Garden - 4344 Shaw Boulevard - Saint Louis, Missouri 63110