Jacquemontia (Convolvulaceae) in Bolivia and Peru

A taxonomic account of Jacquemontia Choisy in Bolivia and Peru is presented. All recognised species from the two countries are described and their distribution, ecology and conservation status are outlined. Separate keys to the species occurring in each country are also provided. All species are mapped and illustrated with line drawings and/or photographs. Five new species, Jacquemontia boliviana J.R.I.Wood, J. chuquisacensis J.R.I.Wood, J. cuspidata J.R.I.Wood, J. longipedunculata J.R.I.Wood and J. mairae J.R.I.Wood & R.Clegg are described from the Andes of Bolivia. Taxonomic notes are provided for many species, J. heterantha Nees & Mart. is treated as a synonym of J. cumanensis (Kunth) Kuntze and J. prominens Helwig of J. unilateralis (Roem. & Schult.) O’Donell. Lectotypes are chosen for Convolvulus agrestis Mart. ex Choisy, C. mucronatus Benth., Ipomoea selloi var. rufescens (Meisn.) Hallier f., Jacquemontia acuminata Rusby, J. azurea var. alba Seeman, J. corymbulosa Benth., J. densiflora Rusby, J. guayaquilensis Meisn., J. pedunculata Rusby, J. sphaerocephala Meisn. and J. violacea var. densiflora Meisn.


Introduction
Jacquemontia Choisy is a medium-sized pantropical genus of around 120 species (Mabberley 2017) but the majority of species are neotropical, the greatest diversity being in Brazil. Most species are modest, twining or trailing species with pretty blue flowers. The genus is of little economic or ecological importance but a few species are cultivated as ornamentals including J. pentanthos (Jacq.) G.Don and J. tamnifolia (L.) Griseb., the former sometimes known as blue clustervine, the latter as hairy clustervine.
There is no monograph of Jacquemontia and the only major study (Robertson 1971) remains unpublished. The genus has the reputation of being somewhat complex at species level as species are reported to intergrade and be difficult to distinguish. There is little information in the literature about their biology or ecology, but it is presumed they are pollinated by bees or similar insects.
The current paper presents a taxonomic account of the genus in Peru and Bolivia and would serve for use in Ecuador, since all recognised Ecuadorian species are covered in the key. The paper aims to help the reader identify the different species and provides information about their distribution, habitat and, in some cases, their flowering patterns. Provisional information on their conservation status is provided, as the exact status of individual species is often uncertain.

Materials and Methods
This paper is based on a study of Jacquemontia in the field and the herbarium. The first author has collected and observed different species of the genus over more than twenty years but has only studied it intensively in Bolivia in the last few years. Herbarium material has been examined at BM, FCQ, K, and OXF in the United Kingdom, at BOLV, HSB, LPB, USZ in Bolivia and at GUAY, LOJA, Q, QCA and QCNE in Ecuador while extensive collections from Peru were loaned by the Field Museum (F) and the Missouri Botanical Garden (MO). A database of over 450 collections from Bolivia and Peru was built up and has allowed generalisations about distribution, habitat and flowering periods to be made. This paper would also have been much weaker without the help of many colleagues who provided collections and photographs, which serve to illustrate species in this paper. Reference has been made to relevant publications, particularly those of O'Donell ( , 1960aO'Donell ( , 1960b and some recent publications from Brazil, especially Buril (2013), Buril et al. (2015), Pastore et al. (2017) and Moreira et al. (2018). Online images from Tropicos (https://www.tropicos.org/), the Field Museum (https://www.fieldmuseum.org/node/4781), Flora do B r a s i l 2 0 2 0 u n d e r c o n s t r u c t i o n ( h t t p : / / reflora.jbrj.gov.br/reflora/floradobrasil/), and especially Jstor (https://plants. jstor.org/) have been in-valuable. The images of Jacquemontia on websites are usually readily identified.
The following account of the genus in Peru and Bolivia relies principally on morphological characters, a wide range of which have proved useful. They include habit (erect vs trailing or twining; herbaceous vs woody), indumentum and leaf shape, especially the base and the apex of the leaf, but leaf size is not without significance. The shape of the inflorescence is often significant, including the number of flowers and the degree of congestion, the shape, size and persistence of bracteoles, the shape, size, and indumentum of the inner and outer sepals, which may be similar or dissimilar, and the colour of the corolla and to a lesser extent its size. Few differences between species have been noted in the androecium or gynoecium and fruit characters have been little used, although they may prove to be useful when more fully known. In consequence they are not included in the diagnostic descriptions of known species.
Short, diagnostic descriptions are provided for all species except new taxa, which are described in full. Selected specimens are cited for all species except rarities and novelties, for which full citations are provided. Many species have been collected from the same location by different collectors and there seems little value in repeating these citations. At least one collection is cited from each province or department from where it is recorded GeoCat (www. Geocat.kew.org/) has been accessed to calculate areas of occupancy and extent of occurrence but conservation assessments have not been made mechanically. Knowledge of individual populations and of known threats to particular areas or habitats have been used to interpret initial results obtained through GeoCAT. However, it is worth noting that assessments based on extent of occurrence seem to produce intuitively more accurate results than those based on area of occupancy, for example, the widespread and common Bolivian species, Jacquemontia evolvuloides (Moric.) Meisn. is classified as Least Concern (LC) based on extent of occurrence but Endangered (EN) based on an area of occupancy of 156,000 km 2 . Other similar conflicting examples include J. cumanensis (Kunth) Kuntze and J. lorentzii (Kuntze) Peter ex O'Donell. In many cases, perhaps all cases, our data is inadequate in one or more aspects including the probable number of locations and the size of individual populations. The assessments provided are essentially tentative and could be more accurate with robust population data and information on the current threats, something which is rarely available for tropical plants. Observations in the field in 2019 suggest that several species, notably Jacquemontia tamnifolia (L.) Griseb., may produce quantities of seed that lie dormant for many years until an environmental change, such as fire, stimulates germination. Assesssments are based on the presence of individual species in Peru and Bolivia separately and not on the plant's global distribution.
As well as some variation in pollen structure (Buril 2013), Jacquemontia is noted for variation in the number of arms of the branched hairs present in many species. The number of arms is often reported to be species-specific but this is not always an easy character to see and, as most species are reported to have 3-armed hairs, it is of limited diagnostic value. Some species, J. evolvuloides and J. unilateralis, are known to be variable in hair type. Consequently, little emphasis has been given to this character, although it is mentioned in passing where it is significant.
Although long considered to be closely related to Convolvulus L., recent molecular studies (Stefanovic et al. 2002(Stefanovic et al. , 2003Carine et al. 2004;Buril 2013) show that Jacquemontia is only distantly related despite the somewhat similar stigma structure, linear in Convolvulus but elliptic and somehat flattened in Jacquemontia. These same studies have confirmed the monophyly of Jacquemontia after the exclusion of one or two species, such as J. montana (Moric.) Meisn., but have not yet resulted in a clear infrageneric classification. As with Ipomoea L. (Muñoz-Rodríguez et al. 2019), it is clear that the long-accepted infrageneric classification based on inflorescence structure and dating back to Meisner (1869) cannot be accepted (Buril 2013) but a replacement is not easily established on the basis of our current information.
Although Peru and Bolivia are neighbours and have several species in common, their Jacquemontia flora is rather different as can be readily appreciated by a glance at the maps that accompany this paper. 23 species are recognised for Bolivia whereas only 12 are known from Peru, a striking difference, not the result of under-collecting in Peru but of the absence of the cerrado and chaco habitats found in eastern Bolivia. In Bolivia and Peru, this genus is most likely to be confused with Evolvulus L. as both have small blue or white flowers. Evolvulus, however, never has twining stems with cordate leaves and can always be distinguished by the presence of a style divided at the base into two branches with linear or claviform stigmas. In Jacquemontia, there is a single unbranched style with two elliptic or oblong, often flattened stigmas. DISTRIBUTION & HABITAT. Most of the twining species are plants of open, often disturbed, bushy or grassy habitats. They are frequently found near settlements. The shrubby and erect species are found in forest or in open cerrados and show no propensity to grow near settlements. In Bolivia, the east is the most diverse in terms of species numbers although country endemics are entirely Andean. In Peru, the greatest diversity and endemism are in the dry north near the Ecuador border. The maps accompanying this paper show that even the more widespread species are scattered in their distribution and several (Jacquemontia blanchetii Moric., J. sphaerostigma (Cav.) Rusby, J. tamnifolia) are noticeably less common in Peru than in Bolivia. Indeed, Leaves pubescent, relatively large, mostly 8 -12 × 5 -7 cm, acuminate to fine point. Inflorescence of long-pedunculate, compact, usually many-flowered heads, the peduncle commonly bifurcate at base of head; secondary peduncles and pedicels short, 1 -3 mm; bracteoles 3 -11 × 0.5 mm, linear-filiform, persistent; outer sepals 6 -7 × 1.5 -2 mm, narrowly ovate or lanceolate, long-acuminate, submucronate, glabrous and the apex usually pubescent, inner broader and shorter, ovate, mucronate 5 × 2.5 mm, glabrous, scarious ( Based on an extent of occurrence of 24,609 km 2 , this species would be classified as Near Threatened (NT) according to IUCN guidelines. This would seem the correct categorisation rather than that of Endangered (EN) based on an area of occupancy of 32,000 km 2 . Although there are rather few collections, its occurrence over a wide area and preferred habitat of disturbed bushy places would suggest that it is unlikely to be affected negatively by deforestation. NOTES. Jacquemontia acuminata might be confused with J. corymbulosa but the larger leaves (twice the size), longer, glabrous (usually with pubescent apex) outer sepals up to 6 mm long (not 4 mm) and prominent filiform bracteoles are distinctive. It can also be compared with J. martii Choisy but the larger leaves, denser, many-flowered cymes, more finely acuminate sepals and persistent filiform bracteoles serve to distinguish it.
We doubt very much whether the type locality (Espirito Santo in Cochabamba Dept.) is correct. Bang's localities are often doubtful, for example Bang 875 (Stenostephanus crenulatus (Britton ex Rusby) Wassh.) from "vic. Cochabamba" must be wrong as S. crenulatus is restricted to La Paz and Beni Departments. Another of Bang's problematic locations was previously discussed in relation to Clinopodium axillare (Rusby) Harley (Wood 2011 Perennial vine; stems twining, somewhat woody, tomentose. Leaves petiolate; lamina (1.5 -) 2.5 -6 × (0.8 -) 1.5 -4 cm, ovate, base shallowly cordate, apex shortly mucronate with caducous mucro or retuse, margin entire, both surfaces tomentose; petioles 1 -1.9 cm, tomentose. Inflorescence of usually shortly pedunculate, compact cymes; with 4 -10 flowers, subcapitate in form; peduncles 3.5 -6 (-10) cm, tomentose; outer bracteoles very narrowly lanceolate, 3 -6 × 1 -2 mm, caducous, secondary peduncles 0 -2 mm; bracteoles 3 -4 mm long, linearfiliform, caducous; sepals unequal, 4 -7 × 3 mm, somewhat accrescent in fruit, oblong-ovate to subrhomboid, acuminate, outer sepals abaxially tomentose, inner sepals scarious, glabrous apart from tomentose midrib area; corolla blue-purple or deep blue with darker, acute midpetaline bands, the exterior glabrous, c. 1.5 cm long; stamens included, filaments c. 5 mm long, glabrous, anthers oblong 1.2 -1.5 mm; style 7 -8 mm long, glabrous; stigma bilobed with 1 mm long elliptic lobes, ovary conical. Capsule rounded-ovoid, 5 -6 × 4 mm, glabrous; seeds 2 × 1.5 mm, muricate. Figs 2, 3A.  RECOGNITION. Somewhat resembles Jacquemontia weberbaueri Helwig but differs in the tomentose (not pubescent) indumentum, the leaves rounded, mucronate or retuse with short caducous mucro, equally tomentose on both surfaces (not strongly mucronate, adaxially thinly pubescent except on veins), subcapitate inflorescence (not lax, well-branched inflorescence). Differs from J. longipedunculata in the caducous bracts and bracteoles, the latter only 3 -4 mm long (not 12 -15 mm and overtopping the capitula), as well as the different shaped leaves (rounded and mucronate or retuse, not acute to a short mucro), oblong-ovate to subrhomboid and broadly mucronate (not narrowly acuminate). It also resembles J. velutina Choisy in the tomentose indumentum but differs in the much larger sepals. Based both on an area of occupancy 28,000 km 2 and extent of occurrence of 139.448 km 2 this species would be classified as Endangered (EN) using Criterion B. All collections were made in a very restricted area (Map 3) and most of the woodland has been cleared in the region so habitat quality is clearly in decline. On the positive side, this species seems to adapt well to disturbed bushy ground around fields in areas cleared of trees but always in the near vicinity of woodland relics. NOTES Erect subshrub, mostly 30 -50 cm high; stems woody below, sericeous, wine-coloured on side facing the sun, the indumentum persistent on older parts, the hairs simple and branched. Leaves petiolate; petioles 3 -10 mm; lamina 2 -4.2 × 1.6 × 2.8 cm, ovate, base subcordate to truncate with rounded auricles, apex acute, shortly mucronate, both surfaces minutely tomentellous, abaxially paler. Flowers in solitary, axillary cymes arising from the upper leaf axils, forming a subcorymbose inflorescence, the cymes somewhat dense and manyflowered; peduncles 3 -5.6 cm, sericeous, erect; secondary and tertiary peduncles 5 -13 mm, sericeous; bracteoles linear, 1.5 -4 mm, persistent after the flowers have fallen; pedicels 1.5 -2.5 mm, sericeous; sepals unequal, outer 7 -8 × 2.5 -3 mm, ovate-subrhomboidş hortly acuminate, tomentellous, inner 6 -7 × 2 mm,   lanceolate, acuminate, tomentellous but with glabrous scarious margins; corolla 1.4 -1.6 cm long, campanulate, blue with white midpetaline bands or (rarely) white, glabrous; stamens included; filaments c. 4 mm long, anthers 0.75 mm; style included, c. 5 mm long; stigmas elliptic, c. 1 mm long; ovary conical. Capsule ellipsoid, 4 × 2 mm, glabrous, enclosed by erect sepals, 1-seeded; seeds ellipsoid, pale brown 2.5 × 2 mm. Figs 3B, C; 4A -K. RECOGNITION. Resembles Jacquemontia floribunda (Kunth) Hallier f. in its erect habit and slightly unequal sepals but leaves ovate, 2 -4.4 cm long up to 1.5 times as long as broad (not broadly lanceolate, 4 -7 cm long, at least twice as long as broad), sepals 6 -8 × 4 mm, shortly acuminate, (not 2.5 -3.5 × 2.5 mm, acute to obtuse), corolla c. 1.5 cm long (not 1. This species is very restricted in its distribution being recorded from a very specific habitat from five nearby locations. Unlike most other endemics from this area, it has not been found in similar habitats elsewhere in the deep valleys of the Río Grande and Río Mizque valley system. On the positive side, there is little obvious risk to the habitat and the plant is not eaten by goats. Nevertheless, it should be provisionally categorised as Vulnerable (VU) D2 based on its very limited area of occupancy of < 20 km 2 and the possibility that populations might be at risk from works involved in the proposed construction of a dam in the vicinity, although no current threat exists. ETYMOLOGY. This species is named after the Bolivian department of Chuquisaca, to which it is nearly restricted (see above). NOTE   The single record would suggest that species should be categorised as Critically Endangered (CR) in Peru but nothing is known of the population so Data Deficient would be correct (DD). Jacquemontia corymbulosa is common in coastal Ecuador south of the equator. TYPIFICATION. There are four sheets of Sinclair's collection of Jacquemontia corymbulosa from Guayaquil at Kew, two from Hooker's herbarium and two from Bentham's. All represent this species but the collection from Bentham's herbarium, seen by Austin and labelled by him as holotype is selected as the lectotype.
The specimen of Jacquemontia guayaquilensis at NY is selected as lectotype of that species as it appears to have been annotated by Meisner. Several isolectotypes are more complete specimens.
The possible holotype of Jacquemontia azurea var. parviflora Choisy at Geneva (G00227359) is not annotated by Choisy and does not indicate that it originates from Herb. Delessert, nor does the numbering coincide with that given in the protologue, but there seems to be no alternative type material at Geneva. The specimens at K and OXF probably belong to the same collection. NOTES. As understood here, this species is almost endemic to Ecuador but its delimitation has been a matter of dispute. The record from Bolivia (Wood et al. 2015) is erroneous. Austin (1982a) included Jaquemontia unilateralis (as J. prominens Helwig) within his concept of J. corymbulosa so extending its range to southern Peru. We think this was wrong as the two species are easily distinguished by the shape of the sepals, J. unilateralis having elliptic-rhomboid sepals. More recently J. corymbulosa has been recorded from eastern Brazil (Buril et al. 2015; Flora do Brasil 2020 under construction). We have not had the opportunity to examine material from Brazil named J. corymbulosa but the occurrence of this coastal Ecuadorian species in Brazil seems unlikely.
Jacquemontia corymbulosa superficially resembles J. acuminata from Bolivia but differs in the smaller (< 6 cm long) leaves with abruptly mucronate tips, much shorter, densely pubescent sepals and the absence of the long linear bracteoles characteristic of that species. ( (Hassler 1911: 194 A categorisation of Endangered (EN) based on an area of occupancy of 88,000 km 2 is quite wrong as the number of collections do not represent its real local abundance. TYPIFICATION. No lectotype of Jacquemontia heterantha var. multiflora has been selected as no specimen from Geneva has been seen. NOTES. As far as we know, Jacquemontia heterantha has never previously been treated as a synonym of J. cumanensis but there seems to be no morphological distinction between the two species so we have here adopted the older name.  Buril et al. (2015). At Corrientes (CTES) specimens of this species were identified as Jacquemontia lorentzii by Antonio Krapovickas. This is strange as both J. heterantha and J. cumanensis are older names. Most specimens of J. lorentzii and J. cumanensis are easily distinguished by the sepals, rhombic with cuneate base in the former, ovate, cordate in the latter, although some specimens with immature sepals can be difficult to name.

Convolvulus agrestis
DISTRIBUTION & HABITAT. Locally common in dry areas of Central America from Arizona south to northern Colombia and Venezuela; largely absent from equatorial regions including Peru but widely distibuted in dry areas of southern Bolivia, northern Argentina, eastern Paraguay and central and north eastern Brazil. In Bolivia, it is frequent in sandy areas of the Santa Cruz lowlands including much of the Chiquitania but is also frequent in the dry inter-Andean valleys of the Río Grande catchment area reaching about 2600 m near  Robertson (1971), this work is an unpublished PhD thesis. In order to avoid any uncertainty about the validity of the lectotypification, M-0174135 is formally designated here as lectotype of Convolvulus agrestis.
The corolla is often reddish in the centre and the indumentum is very variable both in the amount and form of the hairs. Molecular studies (Buril 2013) suggest, unsurprisingly, that this species is closely related to Jacquemontia sphaerostigma. Erect branched subshrub 50 -100 cm high. Leaves broadly to narrowly ovate, 3 -8 × 1.5 -3 cm, obtuse and shortly mucronate, both surfaces softly tomentellous. Inflorescence of pedunculate, dense to lax, axillary cymes; peduncles 1 -6 cm; sepals narrowly elliptic 2.5 -3.5 × 2 -2.5 mm, obtuse, outer tomentose, inner tomentose only in central part; corolla 1.2 -1.3 mm. This threat may not be serious for this locally common species but evaluation of its populations will be needed to confirm this. NOTE. Jacquemontia floribunda is the only erect subshrub amongst the Jacquemontia species that grow in Peru. Based on its similar morphology, it appears to be related to J. chuquisacensis from Bolivia but the sepals are almost half the size and narrowly elliptic rather than subrhomboid and the corolla is distinctly smaller. J. floribunda usually has larger, more cordate leaves although this is not consistent. Molecular Studies (Buril 2013) also suggest a relationship with J. nodiflora. ( Slender usually decumbent herb; leaves subsessile with petioles < 5 mm long, oblong-elliptic, apex mucronatecuspidate, thinly pubescent. Inflorescence lax, few-flowered, usually with 1 -2 (-4) flowers; sepals subequal, lanceolate, obtuse, scarious-margined, ciliolate, sometimes also abaxially thinly pubescent, 6 -7 mm long; corolla white, 2 -2.2 cm. Figs 10A This is a cerrado species and the cerrados are disappearing rapidly in Bolivia and elsewhere. Of its three known locations in Bolivia, it is probably extinct at one (Ñuflo de Chávez) and at another (San Juan Bautista) it is dependent on the conservation of its habtat by a private landowner's family. The third location (Huanchaca 1 in the P.N. Noel Kempff Mercado) lies in a protected area but we have no idea of its frequency and it has not been found in other parts of this national park. This species is at least Endangered (EN) in Bolivia but should current trends continue will probably be upgraded to Critically Endangered (CR). Studies should be undertaken to establish the status of this species in the P.N. Noel Kempff Mercado as a matter of urgency. NOTES. Preliminary molecular studies (Buril 2013) suggest this species is most closely related to Jacquemontia estrellensis, rather than J. mairae, which it superficially resembles in its lax inflorescence with white flowers. ( (Austin 1998: 418) should be rejected as this number was not cited by Choisy and is, additionally, represented by two sheets. NOTE. Molecular studies (Buril 2013) suggest this is an isolated species in Jacquemontia. It is very distinctive because of the annual habit, large accrescent outer sepals and the white corolla with dark reddish-purple centre. The hairs are 3 -6-armed but this is often difficult to discern. Twining herb of unknown height but vigorous and probably reaching at least 1 m, indumentum of simple and 2 -3-branched hairs; stem densely pubescent.

Jacquemontia longipedunculata
Leaves petiolate, 1.6 -11 × 0.5 -5 cm, ovate, acute and very shortly mucronate, base cordate, margin undulate, both surfaces tomentellous, minutely punctate, veins somewhat reticulate abaxially; petioles 0.6 -4.5 cm, tomentellous. Inflorescence of dense, long-pedunculate, axillary capitula; peduncles 13 -20 cm long, pubescent; bracts at base of capitulum, petiolate, foliose, 0.7 -2.7 × 0.6 -0.8 cm, oblong, gradually narrowed at both ends, shortly mucronate, tomentellous, persistent; bracteoles at base of flowers, 12 -15 × 1 -2 mm, oblong, slightly overtopping the capitulum so giving it a whiskery appearance; pedicels 0 -2 mm; sepals slightly unequal, outer 7 -8 × 2 mm, narrowly ovate, acuminate, villous, inner 5 -6 × 2 -2.5 mm, broadly oblong, glabrous except for the villous margins; corolla 10 -14 mm long, blue, glabrous, narrowly tubular, the limb weakly spreading with the midpetaline bands terminating in a tooth; stamens included, filaments 4 -5 mm long, anthers c.   giving it a whiskery appearance. The sepals are also distinctive, the outer tomentose, the inner glabrous with villous margins. Unlike other Bolivian and Peruvian species, it somewhat resembles Jacquemontia guayanensis (Aubl.) Meisn. in its inflorescence structure and indumentum but the prominent bracts and bracteoles distinguish it. DISTRIBUTION NOTE. Jacquemontia lorentzii has been both neglected and misunderstood. It is characterised by the ovaterhomboid, acute to shortly acuminate sepals. These are very small in immature specimens but are accrescent and quite large in fruiting examples. It has been confused with J. cumanensis and a few specimens are somewhat indeterminate in their sepal shape, for example Parada & Rojas 2514, but J. cumanensis is usually easily distinguished by the cordate sepals. The sepals of J. lorentzii actually resemble those of J. unilateralis, especially the forms found at Sorata, but the inflorescence is usually lax and somewhat diffuse unlike the subcapitate inflorescence of J. unilateralis. The shape of the sepals also somewhat recalls those of J. pentanthos but the texture and indumentum is very different from the papery sepals of that species, the bracteoles are deciduous and the inflorescence usually much laxer.  Slender twining perennial; stems and young growth thinly pubescent but eventually glabrescent. Leaves petiolate; petioles 0.3 -2.5 cm, pubescent; lamina 1.2 -5.8 × 0.7 -3.9 cm, ovate-deltoid, base truncate, apex acute to shortly acuminate, margin entire, both surfaces subglabrous with a few scattered hairs, these sometimes 2 -3-branched, abaxially paler, the veins with scattered hairs.
Capsule subglobose, 4 -5 mm diam., glabrous, brown, 8-valved, 4-seeded; seeds ovoid, 2.5 × 2 mm, glabrous. Figs 13A -F, 14A. RECOGNITION. In Bolivia, this species is only likely to be confused with Jacquemontia blanchetii, which grows in the same area. J. blanchetii differs in being glabrous with a blue corolla < 2 cm long and shorter obtuse to rounded sepals < 4 mm long. J. mairae has a larger white corolla, 2.2 -2.5 cm long, shortly mucronate sepals 5.5 -6 mm long and is puberulent on young plants, particularly the petioles, peduncles and pedicels. It also resembles the Peruvian J. elegans Helwig but the corolla is white (not blue), the sepals are glabrous and mucronate (not comose, nor rounded, obtuse). In its white flowers it has some resemblance to the cerrado species J. gracilis but the leaves are nearly glabrous (not pubescent), markedly petiolate with petioles up 2.1 cm long (not subsessile with petioles < 5 mm long), ovate-deltoid up to 3.5 cm broad (not oblong-elliptic, < 2.5 cm broad), the base truncate (not rounded to cuneate), the apex shortly acuminate (not mucronate), the sepals completely glabrous (not pubescent to ciliolate) and the corolla 2.2 -2.5 cm long (not 1.5 -2 cm long). DISTRIBUTION    here, isolectotypes MICH-1111330, MIN-100289, NY-00319293, NY-00319295, US-00111303, US-00111304). Jacquemontia rusbyana Standl. (Standley 1936: 172 (Rusby 1845) and an unlocalised collection by Bang (No. 2849) after the description of Jacquemontia densiflora Rusby but the latter should be excluded as a type, as Rusby considered it a "more tomentellate form" of the new species. There are three sheets of Rusby 1845 at NY all annotated as "type col" but we have selected the sheet labelled holotype by E. K. Schofield (NY-00319294) as lectotype to avoid ambiguity. DISTRIBUTION  Least Concern (LC), although this might require revision in the case of Peru, as it clearly diminishes in frequency northwards with only two records from Ecuador (Austin 1982a). NOTES. Jacquemontia pentanthos is very variable in floral dimensions and in inflorescence indumentum. The inflorescence (including bracteoles and sepals) appears always to be glabrous in Bolivia and usually so in Peru, but is sometimes pubescent elsewhere. Plants from Bolivia, Peru and Brazil have smaller corollas and shorter sepals than plants from Central America. They were previously treated as a distinct species J. densiflora. The two forms are usually easily distinguished and J. densiflora may merit recognition at subspecific rank.
Very characteristic of this species are the papery rhomboid sepals which differ in texture from those of all the other species occurring in Peru and Bolivia. 20. Jacquemontia peruviana Helwig (1927: 1138 A twining perennial with thin woody stems. Leaves ovate or oblong-ovate, relatively small (5 cm long), brownishtomentose, the base shallowly cordate, and the apex rounded and mucronate. Inflorescence very compact; peduncles elongate; sepals 9 -10 (-14) mm in length, somewhat unequal, tomentose, ovate-acuminate terminating in a distinct aristate point; corolla blue, 17 -20 mm long. The seeds have a distinctive winged margin. Fig. 16. HABITAT. In Peru, known only from the two old collections cited above but quite frequent in southern Ecuador, where it grows in very dry scrub between 1300 and 1700 m. Map 14. We have seen 10 collections from Ecuador including the following: There has been no record from Peru for more than a century so it is possibly Extinct (EX) in that country. There are, however, several, apparently healthy populations in southern Ecuador. NOTE. There are no extant specimens of Jacquemontia caudata but this is here united with J. peruviana based on the photographs of the Berlin types at F, the protologue and the sketches of the two calyces associated with the type collections. Both species come from Cutervo Province in Cajamarca at similar altitudes (1300 -1600 m), are similar in their indumentum and 17 -20 mm long, blue corolla, differing in the sepal length (10 mm long in J. peruviana but 14 mm in J. caudata) and the long terminal mucro on the leaf in J. caudata. Given the absence of distinguishing features except the calyx dimensions and the geographical proximity of the two collections, they are best treated as a single species. It should be noted that the specimens cited from Ecuador all conform more closely to the type of J. peruviana than to that of J. caudata. Jacquemontia peruviana appears to be related to J. weberbaueri having the same mucronate leaf tips and similar indumentum, but differs in the much longer aristate sepals.  extensive fire in areas of dry forest near San Miguel, it was the most abundant creeper climbing over dead trees over a considerable area, suggesting that seeds may remain dormant until propitious circumstances, such as fire or ash, encourage germination.  specimens available, none of these differences holds up, so we agree with Macbride (1959) that J. prominens should be united with J. unilateralis. Austin (1982a) went further uniting J. prominens with J. corymbulosa but the sepals of the two species are very different although a few specimens collected where their ranges overlap might be considered intermediate such as S. Llatas Quiroz 3151 (F) from Portuchuelo de Olmos, Lambayeque, Peru or C. Sandeman 34 (OXF) from Salinas in Ecuador. At the other end of the range of J. unilateralis, the three collections from the Sorata region of Bolivia have smaller sepals (4 -5 × 3 mm) and a smaller corolla, only 13 -17 mm in length. These specimens thus approach J. lorentzii but differ in the persistent bracteoles, short petioles and relatively dense inflorescences. Slender twining herb, all vegetative parts densely tomentose. Leaves ovate to suborbicular, rounded to obtuse, mucronate; petioles usually short 1 -2 (-3) cm. Inflorescence compact; bracteoles linear, 1 -2 mm, inconspicuous; pedicels 1 -3 mm; sepals subequal, ovate to elliptic, obtuse to rounded, usually less than 4 mm long, outer tomentose, inner with broad scarious margins; corolla relatively narrow, dull pink, white or blue, 13 -17 mm. Fig. 18C, D. TYPIFICATION. The type specimen at Brussels exactly corresponds to Choisy's citation of "herb. Martius n. 37" and is annotated by Choisy. Specimens at M and W are, therefore isotypes. DISTRIBUTION  Unlike Jacquemontia cumanensis, another species of eastern Bolivia, this is a Cerrado, rather than a Chaco species as is clear from its distribution in Bolivia and Paraguay.
Decumbent perennial herb, with long stems, all parts densely villous with long spreading apparently simple hairs. Leaves subsessile, oblong elliptic, narrowed at both ends, acute, numerous, the internodes short; inflorescence of few terminal and axillary racemes, 2 -5 cm in length, the flowers imbricate; bracteoles linear-lanceolate, acute, villous; sepals subequal, linear, acute, erect, 6 -7 × 0.5 mm, villous; corolla pale blue, c. 1 cm long. This species is globally rare and should be treated as Critically Endangered (CR) in Bolivia as it is known from a single collection. Even though the collection locality is in a protected area, the absence of other collections suggests it is very rare and the only population could be lost by any habitat change, such as the development of scrub. NOTES. Field notes accompanying the Bolivian collection describe this plant as a decumbent perennial. very grateful to Denis Filer and John Baker for help with databases, maps and plates, to James Ritchie for help with the scans, to Serena Marner for processing loans and to Rosemary Wise for preparation of the line drawings that illustrate species described and discussed in this paper.
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