taxonID	type	description	language	source
EFFC549DCED0564FA47F85CD2FB69CFF.taxon	description	Figs 1 A, B, 2, 3 A	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
EFFC549DCED0564FA47F85CD2FB69CFF.taxon	description	Description. Trees, 2 – 16 m tall. Leaves: petioles 6 – 12 cm long, leaf blades 33 × 20.5 – 21 cm, widely ovate, concolorous to discolorous, bases cordate, margins entire, apices acuminate, stellate trichomes above and below. Inflorescences long peduncled; flowers attached on second or third order axes. Capsules apocarpous, 1.2 – 1.3 cm long, depressed-globose, wings absent.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
EFFC549DCED0564FA47F85CD2FB69CFF.taxon	distribution	Distribution and habitat (Fig. 2). Mexico, Belize, Costa Rica, Nicaragua, Venezuela, Guyana, Ecuador, and Brazil (Ceará, Maranhão, Mato Grosso, Pará, Pernambuco, Rio de Janeiro, Rondônia, Roraima and Tocantins), Central and West Africa, and Madagascar. In Brazil, Tschá et al. (2002) indicated the species occurred in Alagoas state but the specimen they cited (M. T. Monteiro 22831) is actually a species of Cordiaceae.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
EFFC549DCED0564FA47F85CD2FB69CFF.taxon	etymology	Etymology. The specific epithet refers to the African continent, where the type was collected.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
EFFC549DCED0564FA47F85CD2FB69CFF.taxon	discussion	Discussion. Christiana africana is easily distinguished from its congeners as it is the only species with a fully apocarpous gynoecium and capsule. The African-American distribution of Christiana africana is an unusual biogeographic pattern. Burret (1926) postulated a natural migration of Christiana from Madagascar westward to Africa and eastward via the Pacific to South America but there are no obvious adaptations for such long-distance dispersal and the American collections of C. africana do not support an indigenous presence; C. africana occurs sporadically and is invariably found in either secondary vegetation or near households. Kubitzki (1995), also confronted by the odd pantropical distribution of Christiana, simply reiterated Burret’s argument. There are relatively few examples of flowering plant taxa with an amphi-Atlantic disjunction (Thorne 1973; Renner 2004), which mostly can be attributed to long-distance dispersal. Renner (2004) suggested that unlike family or genus level disjunctions between America and Africa that fit this long-distance dispersal hypothesis, species level disjunctions often might be anthropogenic. An alternative hypothesis is that Christiana africana, at least, was introduced into the Americas by African slaves during the trans-Atlantic slave trade. Superficially, its seeds resemble in shape, color, and lack of indumentum those of castor bean (mamona), Ricinus communis L. (Euphorbiaceae) (Fig. 3), which is native to Africa, and which was brought to the Americas by slaves as a medicinal plant (see e. g., Voeks 1997, 2013; Carney 2013). This would explain its atypical distribution in the Americas and the hypothesis could be tested by a detailed genomic analysis of African and American populations. The four other South American species of Christiana are clearly native and although collected infrequently, they are found in undisturbed habitats. Christiana africana is “ pollinated ” (i. e., visited) by lepidoptera (fide Cornejo & Bonifaz 5054, in sched.). Hooker (1849) based Christiana cordifolia Hook. f. on a Vogel collection housed in Kew. In this herbarium, there are three duplicates of Vogel 200, and we designate here one of them (K 000241734) as the lectotype of this name as it has Vogel’s detailed annotations about locality according to protologue. Carpodiptera schomburgkii Baill. was described by Baillon (1872) based on a collection by R. H. Schomburgk (800) from Guyana. The material studied by Baillon is deposited in Paris (Stafleu and Cowan 1976) where there are now two duplicates of this collection. We designate here the most complete specimen with flowering branch (P 02143016) as lectotype. An isolectotype at P appears to have Baillon’s notes and sketches while an isolectotype at B † was annotated by Burret. Baillon (1885) described Christiana madagascariensis Baill. based on a collection by Hildebrandt 3262 also housed in Paris. There are two duplicates of this collection now in this herbarium, and we designate one of them (P barcode P 00077799) as the lectotype as it not only is representative but also has Baillon’s detailed annotations about the species. Speirostyla Baker was proposed by Baker (1889) as a new monotypic genus endemic to Madagascar. Simultaneously, he described S. tiliifolia Baker based on two syntypes: Baron 5742 and Hildebrandt 3262. Capuron (1963) distinguished between the syntype collections when he stated that the latter was the “ Typus ” of this name, but he failed to distinguish between duplicates of the Hildebrandt collection. A second-step lectotype therefore is designated here.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
9172E5BB5E0F5394AB1373A3981F2467.taxon	type_taxon	Type. Christiana africana DC.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
9172E5BB5E0F5394AB1373A3981F2467.taxon	distribution	Distribution. A genus of six species found in Mexico, Central and South America, Africa, Madagascar, and French Polynesia, with Brazil where there are four species, two of which are endemic as its main center of diversity. The genus is primarily found in rainforest ecosystems.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
D05F4FB221865EA2A157CE6DB5ACFBBF.taxon	description	Fig. 2	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
D05F4FB221865EA2A157CE6DB5ACFBBF.taxon	description	Description. Trees, 4 – 5 m tall. Leaves: petioles 1.8 – 3.7 cm long, leaf blades 15.5 – 40.5 × 7.5 – 18 cm, ovate, discolorous, bases truncate to subcordate, margins entire, apices acuminate, stellate trichomes above and below. Inflorescences long peduncled; flowers on second order axes. Capsules syncarpous, 2 – 2.5 cm long, subturbinate to turbinate, wings inconspicuous.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
D05F4FB221865EA2A157CE6DB5ACFBBF.taxon	distribution	Distribution and habitat (Fig. 2). Endemic to Ecuador at 590 – 610 m elevation. Christiana eburnea occurs in areas of mangrove with influence of Savanna and Deciduous Forest. The report (Dorr 1999) of C. eburnea occurring in Peru was based on the misidentification of a specimen (Schunke V. 5516) properly referred to C. mennegae (Jans. - Jac. & Westra) Kubitzki as reported by Barbosa-Silva et al. (2021).	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
D05F4FB221865EA2A157CE6DB5ACFBBF.taxon	etymology	Etymology. From the Latin ‘ eburneus, eborinus ’ meaning ivory-white with yellow tinge, a reference to the petal color according to the protologue.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
D05F4FB221865EA2A157CE6DB5ACFBBF.taxon	discussion	Discussion. Christiana eburnea is recognized by its fasciculate inflorescences with flowers arranged on second order axes and subturbinate to turbinate capsules, features that differentiate it from C. restingae. This species was described as a novelty discovered in the Kew Herbarium (K) and its protologue states “ Ecuador. Chonana [sic] near Guayaquil, Spruce 6260. ” A specimen in Herbarium Hookerianum (K) labeled by Sprague “ Asterophorum eburneum, Sprague nov. gen et sp. Brownlowiearum ” has Sprague’s notes and sketches and the exact locality cited in the protologue but it is numbered “ 6260 bis. ” This specimen most closely matches the information given in the protologue and is designated here as the lectotype. We imagine that Sprague either miscopied the collection number or the word “ bis ” was added to the label later. Another specimen in Herbarium Hookerianum (K), also labeled by Sprague, has a copied label with the locality “ prope Guayaquil ” and the number 6260 bis. It clearly is a duplicate of the former. Additional Spruce material (BM, G, MPU, and P) labeled “ Ad fluvium Daule prope Guayaquil ” has the number “ 6260 ” as cited in the protologue but this material lacks the precise locality that was given even though Chonona, an indigenous locality, eventually was subsumed by the municipality of Daule (Jijón y Camaño 1919). Given the locality conflict, these specimens are considered original but not type material. Finally, two herbarium sheets of Spruce 6260 in Paris (P 02143014 and P 02143015) lack original labels yet have Baillon’s sketches and notes; the latter sheet consisting of notes only.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
BE060D663F615ED4A269A0160DB0B6FB.taxon	description	Fig. 2	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
BE060D663F615ED4A269A0160DB0B6FB.taxon	description	Description. Shrubs to trees, 1.5 – 3 m tall. Leaves: petioles 5 – 7 cm long, leaf blades 10 – 15 × 8 – 12 cm, widely ovate to circular, concolorous, bases cordate, margins coarsely dentate, apices acuminate, stellate trichomes above and below. Inflorescences short peduncled; flowers attached to peduncle. Capsules syncarpous, 1 – 1.2 cm long, transversely ellipsoid, wings absent.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
BE060D663F615ED4A269A0160DB0B6FB.taxon	distribution	Distribution and habitat (Fig. 2). Endemic to Brazil, where it is found only in São Paulo state. This species occurs in Savanna and semi-deciduous seasonal forest (Atlantic Rainforest) at 530 – 600 m elevation.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
BE060D663F615ED4A269A0160DB0B6FB.taxon	etymology	Etymology. From the Greek ‘ macr, macro ’ meaning ‘ long, large, great’, and ‘ odus, odon, odontos ’ meaning ‘ teeth’, the specific ephitet probably referring to the conspicuously dentate leaf blade margins.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
BE060D663F615ED4A269A0160DB0B6FB.taxon	discussion	Discussion. Both Christiana macrodon and C. vescoana have dentate leaf blades, but the former species is distinguished by its coarsely dentate margins and fruits not winged (vs. finely dentate margins and fruits winged in the latter). The protologue states that the “ Typus ” is a collection (N. ° 43.987) in the herbarium at São Paulo (SP) but inasmuch as there now are two sheets with this number in that herbarium, one is designated here as the lectotype (SP barcode SP 001662), as it has fruit.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
0BCED60D73C05474A425B958422DE2D2.taxon	description	Figs 1 C, D, 2	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
0BCED60D73C05474A425B958422DE2D2.taxon	description	Description. Trees, 5 – 17 m tall. Leaves: petioles 1.8 – 5.5 cm long, leaf blades 12.3 – 29.5 × 5 – 9 cm, narrowly elliptic, lanceolate or oblanceolate, concolorous, bases rounded to obtuse, rarely subcordate, margins entire, apices acuminate to cuspidate, stellate-multiangulate and glandular trichomes above and below. Inflorescences short peduncled; flowers attached to peduncle. Capsules syncarpous, 1.2 – 1.8 cm long, depressed-globose, wings conspicuous.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
0BCED60D73C05474A425B958422DE2D2.taxon	distribution	Distribution and habitat (Fig. 2). Found in Suriname, Peru, and Brazil (Amazonas, Mato Grosso, and Pará states) at 500 – 600 m elevation. This species grows in Amazonian Rainforest and areas of evergreen seasonal forest in Savanna (Barbosa-Silva et al. 2021).	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
0BCED60D73C05474A425B958422DE2D2.taxon	etymology	Etymology. The specific epithet honors Dr. Alberta M. W. Mennega, plant taxonomist and wood anatomist (Jansen-Jacobs and Westra 1983).	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
0BCED60D73C05474A425B958422DE2D2.taxon	discussion	Discussion. Christiana mennegae is recognized by its short-peduncled inflorescences. For additional details see the extensive and detailed discussion in Barbosa-Silva et al. (2021).	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
87549214CD5C583DBA3207D2D53F1227.taxon	description	Figs 1 E, F, 2, 4, 5	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
87549214CD5C583DBA3207D2D53F1227.taxon	diagnosis	Diagnosis. Christiana restingae resembles C. mennegae but can be distinguished by its elliptic (vs. narrowly elliptic, lanceolate, or oblanceolate) leaf blades, calyces with stellate only (vs. stellate and glandular) trichomes, and capsules with inconspicuous (vs. conspicuous) wings.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
87549214CD5C583DBA3207D2D53F1227.taxon	description	Description. Trees, 4 – 11 m tall, functionally dioecious. Branches whitish, cylindrical, rugose, lenticels circular to oblong, 0.5 – 1 mm long, old branches glabrescent, trichomes stellate-multiradiate, sessile, ferrugineous, sparsely distributed, stipules caducous. Leaves alternate, spirally arranged; petioles 1.3 – 3 cm long, discolorous when compared to the branches, vinaceous, inconspicuously striate, not canaliculate, terete, not decurrent, sparsely pilose, trichomes stellate-multiradiate, ferrugineous, more concentrated near the branches; leaf blades entire, coriaceous, nitid when dry, concolorous to quickly discolorous, 5.5 – 13.5 × 3 – 7 cm, elliptic, bases round to subcordate, margins plane, entire, apices acuminate to cuspidate, glabrous or glabrescent above and below, but with stellate-multiradiate trichomes sparsely distributed along the veins, and glandular-sessile trichomes on the blade below; venation actinodromous, 6 – 8 pairs of secondary veins, 2 pairs basal, impressed above, prominent below. Inflorescences axillary, umbellate with flowers attached to peduncles; bracts caducous; peduncles whitish, striate, 5 – 5.5 cm long, glabrous to glabrescent, trichomes sparse. Floral buds globose, ca. 2.5 × 2.5 mm. Flowers functionally unisexual; bracteoles c. 3.5 × 0.9 mm, elliptic, abaxial surface pubescent; pedicels 1.8 – 2 mm long, densely pubescent, trichomes stellate-multiradiate, ferrugineous, sessile. Pistillate flowers: calyx gamosepalous, 5 - merous, cupuliform, c. 4.5 mm long, with apical lobes free, pubescent abaxially, trichomes stellate-multiradiate, lobes c. 2.5 × 2 mm, ovate, apex acute. Corolla dialypetalous, 5 - merous, white, petals c. 2.8 × 1.3 mm, obovate, glabrous, apices rounded. Androecium polystemonous, staminodes 1.4 – 2 mm long, filaments 1.2 – 1.8 mm long, glabrous, anthers c. 0.3 mm long, divergent. Gynoecium 5 - carpellate, ovary ca. 1.2 × 1 mm, depressed globose, densely pubescent, trichomes stellate-multiradiate, style hirsute, trichomes stellate-multiradiate, stigma not observed. Staminate flowers: not observed. Fruit a capsule, woody, syncarpous, c. 1.5 cm long, 1.3 – 1.7 cm diam., depressed-globose, 4 – 5 - locular, inconspicuously winged, c. 0.6 × 0.6 mm, densely pubescent abaxially, glabrous, lustrous internally; seeds 1 per locule, 5 × 4 mm, ellipsoid, variegated, gray with brownish marks, glabrous.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
87549214CD5C583DBA3207D2D53F1227.taxon	distribution	Distribution and habitat (Fig. 2). Christiana restingae is known only from Espírito Santo state, in Vila Velha and Presidente Kennedy municipalities, and in the northeast of Rio de Janeiro state. This is the only species of the genus occurring in the state of Espírito Santo. The new species is found in the Atlantic Forest phytogeographic domain, where it grows in Dense Ombrophylous Forest, as well as in Restinga, at 5 – 300 m elevation. The Brazilian coast has an intense history of plant collecting, especially in the coastal region of the states of Espírito Santo and Rio de Janeiro. Recently, Dutra et al. (2022) with the Espírito Santo Flora Project strengthened floristic and taxonomic studies in the state, including new collections in Restinga areas (Guarnier et al. 2022).	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
87549214CD5C583DBA3207D2D53F1227.taxon	etymology	Etymology. The specific epithet refers to Restinga, vegetation typical of the Brazilian coast, characterized by sandy soil, where the new species is usually found.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
87549214CD5C583DBA3207D2D53F1227.taxon	discussion	Discussion. Christiana restingae is described here three decades after it was first collected by O. Zambom and M. Fernandes. Ironically, it is worth mentioning that most of the large botanical research centers in Brazil are concentrated in the central region of the Atlantic Forest, and this is where most Brazilian plant taxonomists are based. This underscores the lack of attention Christiana has received in recent years (Barbosa-Silva et al. 2021) and the paucity of specialists knowledgeable about certain groups of plants. Christiana is a genus with homogeneous morphology, sharing stellate trichomes on the vegetative and reproductive parts including inflorescences and flowers. Using a Scanning Electron Microscope (SEM), Barbosa-Silva et al. (2021) discovered the occurrence of simple, two-armed, and glandular trichomes on the petioles and leaf blades of C. mennegae, characters known only from this species. Leaf shape and capsule morphology can be useful to distinguish the different species. Christiana africana, the most widespread species of the genus, has an apocarpic gynoecium and fruit, which is an apomorphy. On the other hand, C. macrodon is the only species with leaf blades that are serrate along the entire length of their margins. Analyzing the type of C. vescoana, it was observed that in a few specimens the leaf blades near the apex also have this leaf margin characteristic, albeit less pronounced. Christiana restingae is characterized especially by its elliptic leaf blades and fruits with inconspicuous wings. It has the shortest leaf length among the species of the genus, with mature leaf blades as small as 5.5 cm long. The new species differs from C. africana and C. macrodon by its elliptic leaf blade with rounded to subcordate (vs. widely cordate and cordate) bases. It also is distinguished from C. africana by its syncarpous (vs. apocarpous) capsules and from C. macrodon by leaf blades with entire (vs. dentate) margins. Although, morphologically, the new species is more similar to C. mennegae in having nitid leaves when dried, glabrescent, and with trichomes especially on the veins, C. restingae is distinguished by having smaller leaf blades (5.5 – 13.5 × 3 – 7.5 vs. 12.3 – 29 × 5 – 9 cm) that are elliptic (vs. narrowly elliptic, lanceolate or oblanceolate), and capsules 1.3 – 1.7 cm in diam. and with inconspicuous wings (vs. 3.8 cm in and conspicuous wings). The analysis of structures in SEM brings new insights into understanding the genus, which exhibits various characteristics that can aid in species differentiation. For instance, the leaves of Christiana restingae possess more glandular trichomes than C. mennegae and have stellate-multiangulate trichomes, whereas C. mennegae only has stellate rotate trichomes on its leaves (Barbosa-Silva et al. 2021). Additionally, with SEM, the cell walls of the epidermis of C. restingae are visible, a character not seen in C. mennegae. The epicarp of C. restingae also exhibits a high concentration of stellate-multiangulate trichomes similar to C. mennegae. The seed of C. restingae also has maculae that are medium brown with darker irregular marks like other species in the genus; however, only C. restingae has these openings and crevices (Fig. 5 E), which even can be observed in herbarium material without the aid of magnification. Although these openings and fissures have been found in all fruit-bearing material, we are not sure if they are found in fresh material or if this character occurs only during the drying process of specimens. The seed of C. restingae does not have stomata, a character that was found to be very interesting in C. mennegae and is also present in other Malvaceae species, although it is rare in Angiosperms (Paiva et al. 2006; Barbosa-Silva et al. 2021). Regarding geographic distribution, Christiana restingae is endemic to Espírito Santo and Rio de Janeiro states, occurring in Atlantic Forest and Restinga, sharing the vegetation type with C. africana (Amazonia and Atlantic Forest) and C. macrodon (Atlantic Forest and Cerrado) (Coutinho 2025). Christiana mennegae and C. restingae do not occur sympatrically since the first species occurs in Brazil only in the Amazonian Domain (Secco 2000; Barbosa-Silva et al. 2021). With the discovery of Christiana restingae, the number of species of the genus in Brazil reaches four, making the country the center of diversity. Of the six known species of the genus, two are endemic to Brazil and its Atlantic Forest. It is worth noting that with the Flora do Brasil 2020 project (BFG 2021), various taxonomists were encouraged to monograph different groups. Consequently, plant groups that had long gone without taxonomic revisions, that were neglected, or that were known to be of little interest, were revised. Thus, numerous results have been published in recent years as a result of this careful process of revision in these groups (Giulietti 2020; Andrino et al. 2022; Antar et al. 2022; Asprino et al. 2024; Barbosa-Silva 2024). The same factor also has driven recent studies on the genus Christiana (Barbosa-Silva et al. 2021), as well as the data presented here.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
5258E624DE995E4DB25DD3A608C8E6F4.taxon	description	Description. Trees, 5 – 8 m tall. Leaves: petioles 2.5 – 6.5 cm long, leaf blades 11 – 21 × 7.3 – 11 cm, widely ovate, concolorous to slightly discolorous, bases cordate, margins slightly dentate apically, apices acuminate, stellate trichomes above and below. Inflorescences short peduncled; flowers attached to peduncle. Capsules syncarpous, c. 1 cm long, depressed-globose, wings conspicuous.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
5258E624DE995E4DB25DD3A608C8E6F4.taxon	distribution	Distribution and habitat. Found only on the islands of Moorea and Tahiti in French Polynesia at 100 – 280 (– 600) m elevation. The species is poorly known with relatively few recent collections.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
5258E624DE995E4DB25DD3A608C8E6F4.taxon	etymology	Etymology. The specific epithet honors Jean Nicolas Eugène Vesco, Naval surgeon and botanist, who collected the type.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
5258E624DE995E4DB25DD3A608C8E6F4.taxon	discussion	Discussion. Christiana vescoana shares dentate leaf margins with C. macrodon, but it is distinguished by characters previously mentioned (and also given in the key). For additional details see Florence (2004). The description of Berrya vescoana was based on an unnumbered collection made by M. Vesco in Tahiti: this collection, including duplicates, is now housed in the herbarium in Paris (P). Kubitzki (1995) noted the type was in P, but only wrote “ Vesco a. 1847 (P) ” where “ 1847 ” refers to the year of collection, not a collection number. Five duplicates of this unnumbered collection are found now in P, none of them have the “ a ” noted by Kubitzki, and consequently, we designate the most complete specimen with fruits and seeds (P barcode P 00637093) here as the lectotype. It is also the same specimen that Florence (2004) considered to be the “ holotype. ” When Nadeaud (1873) described Entelea tahitensis he associated it with a single collection (Nadeaud 479) for which he also indicated there were duplicates (“ un nouvel examination de mes échantillons … ”). There therefore is no holotype as indicated by Florence (2004) who stated that one was deposited in G. Additionally, Florence’s statement cannot be interpreted as designating a lectotype since it contravenes the rules of the ICN (Turland et al. 2018; Arts. 7.3, 9.23). Here, we designate as lectotype the only specimen in P (P barcode P 04756684) with fruits.	en	Coutinho, Thales Silva, Barbosa-Silva, Rafael G., Dorr, Laurence J. (2025): A synopsis of Christiana DC. (Malvaceae, Brownlowioideae), with a new species from the Brazilian Atlantic Forest. PhytoKeys 253: 33-56, DOI: 10.3897/phytokeys.253.145350
