Chiococca includes about 35 species of low shrubs, small trees, and twining plants with distinctive fruits. It is characterized by its tissues without raphides, small to medium-sized leaves, interpetiolar triangular stipules that are persistent and aristate, axillary, subcapitate or cymose to racemiform inflorescences with one to several flowers, 4-merous homostylous flowers, tubular-urceolate funnelform corollas with thinly imbricated lobes, stamens that are fused to each other and the disk at the base of the flower, a single cylindrical stigma with 2 lateral stigmatic zones, a bilocular ovary with the ovules solitary in each locule, fleshy white pr rarely pink to purple fruits that are ellipsoid and drupaceous, and 2 1-locular pyrenes. As with other Chiococceae, the leaves are distinctive in their higher-order venation and often secondary veins not being visible.The habit varies among the species, from scrambling vining plants to medium-sized trees. The flowers are generally nodding to pendulous on spreading inflorescences that are borne on spreading branches; herbarium specimens not infrequently give an inaccurate impression of the habit, because they are mounted with the stems and inflorescences ascending, rather than oriented downward as on the live plants. The flowers appear to be insect-pollinated, and the fleshy fruits are presumably bird-dispersed. The fruits frequently dry darkened or blackened on herbarium specimens, which has misled some authors but these are white in life (except in some specimens of Chiococca nitida and Chiococca densifolia).
The flowers are generally 5-merous but the merosity is sometimes variabile (e.g., Chiococca henricksonii, described from two specimens with the type 4-merous and the paratype 5-merous). The corollas are most often white to yellow, but are not infrequently flushed with pink and are sometimes red or purple externally; Lorence et al. (2012) note that the corollas of Chiococca rubriflora are purple externally and orange inside. The largest corollas are those of Chiococca grandiflora and Chiococca rubriflora, 15-20 mm long. The corolla lobes have been widely described as valvate in bud, but observations in this present study suggest they are more likely thinly imbricated, as in related Chiococceae genera.
Chiococca plants are often frequent locally, especially in secondary vegetation and especially Chiococca alba. Chiococca belizensis and Chiococca brachiata are found at the highest elevations in in the wettest vegetation, in the Andes (where Chiococca belizensis is found higher than in Central America).. As with many other Chiococceae genera, the various species of Chiococca are often similar and subtle to separate. The genus has a center of species diversity in Mexico and Central America, and also has a number of species in parts of northeastern and eastern South America. Chiococca alba is the most commonly collected species, and is found throughout the range of the genus; it is also morphologically quite variable, and deserves further study as to its regional populations and systematics.
Chiococca has never been studied as a whole and seems to have several undescribed species (J.G. Jardim, pers. obs., in prep.). Chiococca was studied as a student dissertation project with morphological and molecular data in the 2000's, but that work was centered on plants from Mexico and Central America and those taxonomic results were never finalized or published.Traditionally, nearly all the plants have been included in a widely distributed, ecologically and morphologically varied Chiococca alba. The taxonomy here is a superficial synopsis, but differs markedly from previous treatments. In particular, the majority of the plants from the Andes, which grow in wet, usually premontane and montane habitats, are here separated in Chiococca belizensis, a Central American species that was not previously much recognized in South American floras, and in Chiococca brachiata.This latter name was synonymized with Chiococca alba by Standley (e.g., 1930, 1936), and his taxonomy has been followed until now.
In Brazil, the treatment of Mueller (1881) is still influential but problematic in its application of names. Chiococca was probably an intriguing genus for Mueller, with his eye for relatively small morphological variation, and he named 17 varieties of one of his species. Mueller recognized two species in Brazil, Chiococca nitida and Chiococca brachiata, with the latter species then included by subsequent authors in Chiococca alba (e.g., Standley's floras). However, most of the Chiococca plants in eastern Brazil are found in relatively dry cerrado, restinga, campo rupestre, and caatinga vegetation, and share relatively an erect shrub habit generally 1-3 m tall, relatively small leaves, and relatively short inflorescences positioned among the leaves. These plants correspond in these characters to Martius's Chiococca densifolia, and that name is resurrected here for the common Chiococca species in eastern South America to, at least, stimulate further study. Mueller's Chiococca brachiata corresponds here to a mixture of Chiococca alba and Chiococca densifolia; none of the Brazilian plants he treated match the Peruvian type of Chiococca brachiata in morphology or habitat, but it is not known what comparative material he had of that Andean species.
Chiococca is quite similar to some other genera, especially of Chiococceeae, and thase have been variously separated and combined. These are circumseribed here following the molecular analysis of Paudyal et al. (2018), and the morphological features that separate these genera can be subtle. Several individual Antillean species were separated by them into other, sometimes monotypic genera, and a least one other Antillean species is unusual morphologically and perhaps deserves further evaluation, Chiococca capitata.
In general aspect several species of Chiococca are similar to Syringantha, and a few are sympatric with it. For more about their separation, see that web page for that other genus.
Several Chiococca species have been variously included in Chiococca and Salzmannia, and two species have been recently transferred by Paudyal et al. (2018) from Chiococca to this other genus, while Chiococca insularis, which has been suggested to belong to Salzmannia, was placed by by them in Chiococca. For more details of the taxonomic history and confusions of these two genera see Salzmannia's web page. Many specimens of Chiococca nitida seems to have the more ellipsoid, rounded fruit shape and often pink to purple color that Paudyal et al. used to distinguish Salzmannia, but this species was placed in Chiococca by them. Some specimens of Chiococca nitida do have white fruits, so this species may have polymorphic fruit colors as in some Palicourea species from the same region (e.g., Palicourea sect. Egensis).
Asemnantha included one species of low shrubs in southern Mexico and northern Central America. This species is similar in many features to traditional Chiococca, but differs from this genus as it has long been characterized in its inflorescences with one to a few shortly pedunculate flowers enclosed by regularly developed bracts, its well developed calyx limbs, and tubular-urceolate, yellow to cream-colored corollas (vs. pedunculate, usually branched inflorescences with small sometimes irregularly developed bracts, a generally short calyx limb, and funnelform to campanulate white to bright yellow, orange, or red corollas in Chiococca). The data supporting separation vs. inclusion of Asemnantha in Chiococca were equivocal for some time, and these were separated based on inflorescence and corolla forms that were presumed to indicate an evolutionary separation. More recently, the molecular study of Paudyal et al. (2018) found Asemnantha nested within Chiococca and the inflorescence and flower form more variable than appreciated on this clade.
Ramonadoxa includes one species found in eastern Cuba and is quite similar to Chiococca. This species was formerly included in Chiococca, in fact, and is similar in particular to Chiococca alba. Paudyal et al.'s (2018) molecular analysis found this species separated from Chiococca on their cladogram so they separated it taxonomically, but their formal genus diagnosis (2018: 389) noted that they had difficulty finding any morphological characters to separate these. Instead, they diagnosed Ramonadoxa by its molecular characters and its morphological distinctions from Scolosanthus, which is a morphologically quite distinct spiny genus. They noted that they could only separate Ramonadoxa and Chiococca by corolla form and color, "tubular-subcylindrical, purple-brown outside and deep yellow inside" in Ramonadoxa vs. "campanulate to funnelform, white, cream-white to pale yellow throughout" in Chiococca; however, a range of color forms that included pale yellow were noted by other authors and documented on the type collection of Ramonadoxa cubensis. and some other species of Chiococca, such as Asemnantha, have similarly tubular corollas flushed with pink or purple so these features may not actually distinguish these genera.
The study of Coutaportla by Torres-Montúfar et al. (2023) was part of a larger study of the Chiococceaee tribe in Mexico, and they found in comparing the genera that some plants of Coutaportla from northeastern Mexico had been confused with Chiococca. These plants were included in the original description of Chiocoocca grandiflora Lorence & T. Van Devender of northern Mexico, and Torres-Montúfar separated these plants as Coutaportla lorenceana. The specimens that were previously included in Chiococca grandiflora were paratypes, not the type, so the name Chiococca grandiflora is still a separate, accepted species with its description and reported range now emended by Torres-Montúfar et al. They cited Chicocca grandiflora "pro parte" as a synonym in the protologue of Coutaportla lorenceana, which can appear to be problematic nomenclaturally. However, the name Chiococca grandiflora is nomenclaturally attafched only to its type specimen, so their inclusion here of paratype specimens is not a synonymization of that name. Their citation here refers actually to "Chiococca grandiflora sensu Lorence & T. Van Deventer" in a more standard American taxonomic form.
Author: C.M. Taylor.
The content of this web page was last revised on 29 March 2023.
Taylor web page: http://www.mobot.org/MOBOT/Research/curators/taylor.shtml