Biogeographical Relationships and Diversity in the Peruvian Flora Reported by Hipólito Ruiz and José Pavón: Vegetation, Uses and Anthropology

Simple Summary The expedition started by Hipólito Ruiz and José Pavón from Spain to the territories of Peru, Chile and Ecuador in the 18th century yielded a total of 6493 plants from Peru, of which 2327 were used in medicine, cosmetics, food or materials. Information was obtained from their published works, diaries, manuscripts and plant collection. Using a bioclimatic model, we present the types of vegetation from which these plants originate (from the coastal desert to the Amazonian forests), as well as the ethnic groups from which they might have come. Using statistical analyses, we were able to discover which vegetation types were the most explored and the areas from which the most commonly used plants originated. Abstract The Royal Spanish Botanical Expedition to the Viceroyalty of Peru in the 18th century was one of the most important European expeditions to American territories. Using the herbarium sheets of Ruiz and Pavón (Royal Botanical Garden of Madrid) and their edited works, manuscripts and expedition diaries, we have constructed a database of the collected and observed flora, which has served as the basis for a map containing all of the Peruvian localities of the expedition. Based on the method of bioclimatic belts and our own observations, we have deduced to which type of vegetation the flora studied in the expedition belongs. The uses of the flora per locality were studied, as well as the ethnic groups involved in the different localities. By using a Principal Component Analysis, we have obtained the distribution of the bioclimatic belts whose vegetation was the most explored. In order to observe the bioclimatic tendency of plant uses, a Detrended Correspondence Analysis (DCA) was conducted to identify the distribution of localities with the highest frequencies of plant uses. The expedition’s explorations focused on the most humid areas of the thermo- and mesotropical belts, from where a large number of plants with practical uses were obtained.


Introduction
Peru is one of the countries with the greatest diversity of vascular plants in the world [1] and the third most diverse in South America after Brazil and Colombia, with just over 19,000 species [2]. Its geography is divided into three major natural regions [3]: the coast, with a very arid desert; the highlands, starting with the first foothills of the Andes, ranging from communities of succulent plants (Cactaceae) to the grasslands of the puna above 4000 m asl and up to the summits, which, in many cases, exceed 5000 m asl; and the Amazonian slope of the Andes, which begins with very humid forests that continue into the Amazon basin, from about 1000 m asl, with a diversity of up to 300 tree species per hectare [4]. works [6][7][8][9][10][11], diaries and unpublished material was elaborated and transposed into their current toponymies (Supplementary Table S1). Cartographic resources from the 18th century, cartographic software and Peruvian toponymies published since the 19th century were used, including the statistical dictionary by Paz Soldán [27] (Supplementary Table S2). The decimal coordinates of all localities were looked up (Supplementary Table S3). These were used to construct digitized maps of the localities mentioned in the expedition, which were generated using the software Quantum Geographic Information System (QGIS) version 3.10 A Coruña [28].
For each locality, the list of plants collected or observed during the expedition was compiled, and the nomenclature of those indicated in the text was updated according to the herbarium labels of the material studied by other authors and to the IPNI portal [29]. There are species names that were not found and others that do not geographically match their distribution, as they are from outside the territory studied. In these cases, the genus rank was used. In addition, the uses assigned to the plants by the indigenous people of the localities through which the expedition passed were noted and translated according to Cook [30]. Cook established 10 groups belonging exclusively to plants: food (including beverages, for humans only), food additives (processing agents and other additive ingredients used in food preparation), animal food (fodder and feed for vertebrate animals only), materials (wood, fibers, cork, cane, tannins, latex, resins, gums, waxes, oils, lipids, etc., and their by-products), fuels (wood, charcoal, petroleum substitutes or fuel alcohols), social uses (plants used for social purposes that cannot be defined as food or medicine, e.g., chewing and smoking materials, narcotics, hallucinogens and psychoactive drugs, contraceptives and abortifacients, and plants for ritual or religious purposes), vertebrate poisons (plants that are poisonous to vertebrates, both accidental and useful for hunting and fishing), non-vertebrate poisons (both accidental and useful poisons, e.g., molluscicides, herbicides and insecticides), medicines (both human and veterinary medicines) and environmental uses (intercropping and nurse crops, ornamental plants, barrier hedges, shade plants, windbreaks, soil improvers, revegetation and erosion control plants, sewage treatment plants, and indicators of the presence of metals, pollution or groundwater). To Cook's uses, we add that of cosmetics/perfumery (plants used for skin or hair improvement and beautification purposes and plants used for their scent), as we know that the expeditioners knew of plants that the Incas and pre-Incas infused for these purposes [31]. For simplicity, cosmetics/perfumery is treated as "cosmetics" in the Supplementary files, text and figures.
For each locality, there are a number of plants with specific uses, which are listed in Supplementary Table S4.
The bioclimatic zones and intervals of annual precipitation correspond to different types of plant communities formed by the combination of specific flora (Table 1).  [35,36]. Species names according to IPNI [29].

Statistical Analysis
Principal Component Analysis (PCA) was performed to determine how the localities with useful plants from the expedition are distributed among bioclimatic belts and ombrotypes. To observe the bioclimatic trends of plant uses, a Detrended Correspondence Analysis (DCA) plot was generated, where the axes are the uses (Axis 1) and the localities where the expedition collected or observed plants with a higher frequency of different uses (Axis 2). Statistical analyses were performed with the program PAST 4.07b [37].

Map of Ethnic Groups of Peru
The INDEPA map [38] was used to show the territories of the ethnic groups whose plant uses were reported during the expedition, as this map locates the ancestral settlements of all of the indigenous people of Peru.

Expedition Localities
In Figure 1A, we present all of the localities of the expedition (Supplementary Table S3), relating them to the bioclimatic belts and the ombrotypes ( Figure 1B,C). The localities are collections or observation points that appear in the herbarium, works, diaries and unpublished manuscripts of the RSBEVP.

Expedition Localities
In Figure 1A, we present all of the localities of the expedition (Supplementary Table  S3), relating them to the bioclimatic belts and the ombrotypes ( Figure 1B,C). The localities are collections or observation points that appear in the herbarium, works, diaries and unpublished manuscripts of the RSBEVP.

The Plants of the Expedition and the Vegetation of Origin
The RSBEVP reported a total of 6493 plants from 191 localities of Peruvian flora (Supplementary Tables S1 and S3). Of these, the uses of 2327 were reported from 128 localities in Peru (Supplementary Table S4).
Most of the localities visited by the expedition correspond to the thermotropical belt ( Figure 2A); i.e., they correspond to the coastal desert, the first foothills of the western Andes or the eastern thermal Andean forests. In addition, most of them belong to the humid and hyperhumid ombrotypes ( Figure 2B).

The Plants of the Expedition and the Vegetation of Origin
The RSBEVP reported a total of 6493 plants from 191 localities of Peruvian flora (Supplementary Tables S1 and S3). Of these, the uses of 2327 were reported from 128 localities in Peru (Supplementary Table S4).
Most of the localities visited by the expedition correspond to the thermotropical belt ( Figure 2A); i.e., they correspond to the coastal desert, the first foothills of the western Andes or the eastern thermal Andean forests. In addition, most of them belong to the humid and hyperhumid ombrotypes ( Figure 2B).

Expedition Localities
In Figure 1A, we present all of the localities of the expedition (Supplementary Table  S3), relating them to the bioclimatic belts and the ombrotypes ( Figure 1B,C). The localities are collections or observation points that appear in the herbarium, works, diaries and unpublished manuscripts of the RSBEVP.

The Plants of the Expedition and the Vegetation of Origin
The RSBEVP reported a total of 6493 plants from 191 localities of Peruvian flora (Supplementary Tables S1 and S3). Of these, the uses of 2327 were reported from 128 localities in Peru (Supplementary Table S4).
Most of the localities visited by the expedition correspond to the thermotropical belt ( Figure 2A); i.e., they correspond to the coastal desert, the first foothills of the western Andes or the eastern thermal Andean forests. In addition, most of them belong to the humid and hyperhumid ombrotypes ( Figure 2B). The number of plants within the hyperhumid thermotropical belt is the highest, as can be seen in Figure 3, and in turn, this bioclimatic belt is also the one with the greatest diversity of plants observed, from the ultra−hyperarid to the ultra-hyperhumid ombrotypes. In the thermotropical zone, the highest frequency of plants is found in the hyperhumid and hyperarid ombrotypes. For example, the expeditioners collected Erythroxylum coca Lam. in a hyperhumid ombrotype (San Juan de Cocheros, Huánuco, Peru), and the vegetation type of this species is rainforest (Table 1) (Table 1). and observations in the dry to hyperhumid mesotropical belt ( Figure 3). For example, in the subhumid ombrotype, they collected Polypodium calaguala Ruiz (= Campyloneurum an gustifolium (Sw.) Fée (Ayacucho, Peru), commonly used in medicine, providing evidenc of mesophytic forests (Table 1), while in the dry ombrotype, they reported Buddleja incan Ruiz & Pav., used for construction materials and utensils, Cervantesia tomentosa Ruiz & Pav. (= Cervantesia bicolor Cav.) with the same uses in addition to its use as food, and Jarav ichu Ruiz & Pav., used for animal food, materials and fuels (Huarochirí, Lima, Peru), in dicating mesophytic forests and grasslands. The hyperhumid mesotropical belt is of grea interest because it contains rainforest plants such as Cinchona species (C. glabra Ruiz, C hirsuta Ruiz & Pav.), which are used in medicine and for obtaining materials (San Pablo de Pillao, Huánuco, Peru) (Supplementary Table S1). Other interesting species in thes forests are Alstroemeria tomentosa Ruiz    To a lesser extent, Ruiz and Pavón also made a considerable number of collections and observations in the dry to hyperhumid mesotropical belt ( Figure 3). For example, in the subhumid ombrotype, they collected Polypodium calaguala Ruiz (= Campyloneurum angustifolium (Sw.) Fée (Ayacucho, Peru), commonly used in medicine, providing evidence of mesophytic forests (Table 1)  The orotropical and infratropical belts were barely represented in the expedition ( Figure 3). In the orotropical belt, only 39 plants were found in the humid ombrotype, and only 1 was in the subhumid ombrotype. All of them belonged to the grassland biome. In the humid ombrotype, we can cite Rauvolfia flexuosa Ruiz  Ruiz and Pavón also collected plants from the supratropical belt, which is especially humid (Figure 3), where we also find eastern Andean rainforest plants such as Cinchona viridiflora Pav. (= Pimentelia glomerata Wedd.) (Piñayoj, Huánuco, Peru), Acrostichum huacsaro Ruiz (= Elaphoglossum huacsaro (Ruiz) Christ), used in medicine, Berberis glauca DC. and Bocconia frutescens L., used for making utensils and dyeing cloth (Chaglla, Huánuco, Peru).
The orotropical and infratropical belts were barely represented in the expedition (Figure 3). In the orotropical belt, only 39 plants were found in the humid ombrotype, and only 1 was in the subhumid ombrotype. All of them belonged to the grassland biome. In the humid ombrotype, we can cite Rauvolfia flexuosa Ruiz

Distribution of Useful Plants from the Expedition
The PCA in Figure 5 shows how the localities of plants with uses are distributed among the bioclimatic belts and ombrotypes in five groups: A-thermotropical localities from ultra-hyperarid to semiarid zones of the coastal desert; B-infra-and thermotropical The cryorotropical belt is not represented in the expedition.

Distribution of Useful Plants from the Expedition
The PCA in Figure 5 shows how the localities of plants with uses are distributed among the bioclimatic belts and ombrotypes in five groups: A-thermotropical localities from ultra-hyperarid to semiarid zones of the coastal desert; B-infra-and thermotropical Andean localities (Rio Marañón in Jaén; Huánuco, near Jauja, Peru); C-meso-and supratropical dry−subhumid Andean localities (Canta in Lima, Huariaca in Pasco, Higueras and Santo Domingo de Rondós in Huánuco, Peru); D-humid supra-and orotropical localities (Tambo Sarria and Lago Lauricocha in Huánuco, Tarma in Junín, Peru); and E-humid to ultra−hyperhumid Andean montane forests and Amazonian thermo-and infratropical rainforests (Pueblo Nuevo, Tulumayo and Casapillo in Huánuco, Vitoc in Junín, Peru).
The negative values of Component 2 (P) represent the most arid and dry localities, while in the positive part of the axis, the most humid localities are ordered.
The DCA in Figure 6 shows the distribution of plants with uses by their localities. Localities are ordered according to the number of plants with uses in a locality. For example, Canchán (12) (Huánuco, Peru), which is subhumid mesotropical, is very close to "medicines" because it has data for three plants used in medicine but also has one plant used for "materials", "fuels", "vertebrate poisons", and "cosmetics" (see Supplementary  Table S4). Chiuchin (29) (Pasco, Peru), which is dry mesotropical, has up to 14 plants with uses, 3 as "materials", 2 as "food", 8 as "medicines" and 1 as "cosmetics".  Component 1 (It) is ordered from lowest to highest on the ordinate axis, with the most negative parts of the axis corresponding to the supra− and orotropical bioclimatic belts, while the most positive parts correspond to the infra− and thermotropical zones. The negative values of Component 2 (P) represent the most arid and dry localities, while in the positive part of the axis, the most humid localities are ordered.
The DCA in Figure 6 shows the distribution of plants with uses by their localities. Localities are ordered according to the number of plants with uses in a locality. For example, Canchán (12) (Huánuco, Peru), which is subhumid mesotropical, is very close to "medicines" because it has data for three plants used in medicine but also has one plant used for "materials", "fuels", "vertebrate poisons", and "cosmetics" (see Supplementary Table S4). Chiuchin (29) (Pasco, Peru), which is dry mesotropical, has up to 14 plants with uses, 3 as "materials", 2 as "food", 8 as "medicines" and 1 as "cosmetics".
However, in other cases, such as Pampamarca (81) (Huánuco, Peru), which is hyperhumid thermotropical, we have only found three plants with uses, such as "materials", "social uses" and "medicines". Cajamarquilla (10) and La Quinua (62) (Pasco, Peru), both humid supratropical, only present one plant with uses, "fuels" and "materials", in this case with a clear reference to the ancestral and current uses of Polylepis racemosa Ruiz & Pav. In contrast, Pillao (88) (Huánuco, Peru) presents many plants with different uses: 9 as "food", However, in other cases, such as Pampamarca (81) (Huánuco, Peru), which is hyperhumid thermotropical, we have only found three plants with uses, such as "materials", "social uses" and "medicines". Cajamarquilla (10) and La Quinua (62) (Pasco, Peru), both humid supratropical, only present one plant with uses, "fuels" and "materials", in this case with a clear reference to the ancestral and current uses of Polylepis racemosa Ruiz & Pav. In contrast, Pillao (88) (Huánuco, Peru) presents many plants with different uses: 9 as "food", 3 as "food additives", 1 as "animal food", 29 as "materials", 2 as "fuels", 1 as "vertebrate poisons", 15 as "medicines", 5 as "environmental uses" and 6 as "cosmetics"; this abundance corresponds to humid eastern forests ( Table 1). The DCA point cloud becomes more condensed with localities where plants have more uses, which also relate to the thermo-and mesotropical belts ( Figure 3) with a wide range of ombrotypes.

Ethnic Groups, Plants and Uses
The map in Figure 7 shows the ethnic groups of Peru and their coincidence with the localities of the expedition, and it is clearly evident that the expedition had contact with the inhabitants and learned about the uses of the plants. Along the western slope of the territory, we have the Quechua stock, but between Lima and Junín, we can observe different ethnic groups: in Lima Yauyos and Yacaru, and in Junín, Huancas, Tarumas and Xauxas. In the eastern jungles, the expedition's localities coincide with the territories of the Pano, Arawaw and Jíbaro families, particularly with the Yanesha, Uni and Cashibo−Cacataibo ethnic groups. Most of the observations and collections within the genus Cinchona come from the territories of these peoples, as well as Phytelephas macrocarpa, which the expedition undoubtedly observed in Yanesha, Ashéninka and Uni territories.

Ethnic Groups, Plants and Uses
The map in Figure 7 shows the ethnic groups of Peru and their coincidence with the localities of the expedition, and it is clearly evident that the expedition had contact with the inhabitants and learned about the uses of the plants. Along the western slope of the territory, we have the Quechua stock, but between Lima and Junín, we can observe different ethnic groups: in Lima Yauyos and Yacaru, and in Junín, Huancas, Tarumas and Xauxas. In the eastern jungles, the expedition's localities coincide with the territories of the Pano, Arawaw and Jíbaro families, particularly with the Yanesha, Uni and Cashibo−Cacataibo ethnic groups. Most of the observations and collections within the genus Cinchona come from the territories of these peoples, as well as Phytelephas macrocarpa, which the expedition undoubtedly observed in Yanesha, Ashéninka and Uni territories.

Discussion
The herbarium materials of the expedition, edited books on the flora and unpublished manuscripts and diaries offer a great complexity of information, mainly derived from the vicissitudes of the authors, as well as from the difficult orography of Peru.

Plants, Bioclimatic Belts and Landscapes
In the hyperarid thermotropical belt of the Peruvian desert coast [35], the genus Nolana [39] is of biogeographical importance. Ruiz Table S1). According to the unpublished manuscripts, it was Tafalla who collected in the hills of the department of Arequipa, contributing to the first knowledge of the species of the genus Nolana, which served as a basis for later studies [40]. Another emblematic species of the ephemeral plant communities of the hills is Narcissus amancaes Ruiz & Pav. (= Ismene amancaes (Ker Gawl.) Herb.), described in the hills of Amancaes, Chancay, Lima, Lurín and Surco (Lima). At present, this endemism does not exist in the localities where Ruiz and Pavón found it [41] due to grazing and urban expansion.
Ruiz and Pavón cited numerous species in the hyperarid thermotropical coastal belt, e.g., in Amancaes (37 species), Cercado de Lima (31), Chancay (434) and Lima (472) (Supplementary Table S1, Figure 5), where many of them were cultivated. Examples include Ageratum conyzoides L., which comes from Mexico, Croton balsamifer Jacq. (= Croton flavens L.) from Mesoamerica, the Caribbean and Venezuela, Pinus pinea L. from Europe and Theobroma cacao L. from Amazonia [29]. This coincides with the large list of plants compiled by González Laguna [42], which were brought to Lima from other parts of the world, including areas within Peru. From the Iberian Peninsula, Ruiz and Pavón allude to Fumaria officinalis L., Geranium moschatum (L.) L. (= Erodium moschatum (L.) L'Hér.) and Myrtus communis L., with the latter two also being listed by González Laguna [42]. However, others discussed by this author, such as Matricaria chamomilla L., do not appear in Ruiz and Pavón's work, although we could include them among the plants used by the Inca culture [43].
Another important thermo−mesotropical species is Erythroxylum coca Lam., which Ruiz and Pavón discovered in the vicinity of Huánuco, Acomayo, Chinchao, Cuchero, Pozuzo (Tilingo) (Huánuco, Peru), and is cultivated in humid to ultra-hyperhumid areas. They also distinguished the species Erythroxylum acuminatum Ruiz & Pav., which extends to the inland of the infratropical Amazonia of Brazil [29] and which was recently used to clarify new species in Colombia and Panama [44]. However, Erythroxylum coca var. ipadu Plowman (Amazonian coca), which was already known to Europeans in the mid-18th century [45], is not included in the works by Ruiz and Pavón, nor is E. novogranatense var. truxillense (Rusby) Plowman, which comes from the valleys of northern Peru and was cultivated on the coast before the Incas [46].
The flora of the meso− and supratropical levels is very well represented in the expedition flora by the shrubs of Mutisia acuminata Ruiz & Pav. and Periphragnos uniflorus  Table S1), which can be confirmed today [47]. In the supratropical belt of central Peru, Polylepis racemosa forests are also widespread [48]. During the expedition, they were Perhaps the genus most studied by the expeditioners within the orotropical belt is Valeriana, whose species are part of the grasslands or rocky communities at high altitudes [49], such as V.  Table S1, Figure 4), also attract attention.
The humid forests of eastern Peruvian, between the infra-and supratropical belts, are characterized by the relatively frequent presence of species of the genus Cinchona [37], whose importance extends from the expedition to the present day [50], being the subject of some publications by Ruiz [51] and Ruiz and Pavón [52] as well. Its study is one of the main achievements of their expeditions [53,54]. Among the species, C. micrantha is quite widespread in the Amazonian montane forests of central and southern Peru (Figure 8) in the thermo− and infratropical hyperhumid and ultra−hyperhumid bioclimatic zones with tree ferns (Cyathea) and palms (Iriartea deltoidea Ruiz & Pav.) [35]. C. pubescens Vahl ascends in central and northern Peru to the hyperhumid mesotropical belt (Supplementary Table S1), also accompanied by tree ferns [37]. chophylla J.Presl.
Perhaps the genus most studied by the expeditioners within the orotropical belt is Valeriana, whose species are part of the grasslands or rocky communities at high altitudes [49], such as V. connata Ruiz & Pav, V. Figure 4), also attract attention.
The humid forests of eastern Peruvian, between the infra-and supratropical belts, are characterized by the relatively frequent presence of species of the genus Cinchona [37], whose importance extends from the expedition to the present day [50], being the subject of some publications by Ruiz [51] and Ruiz and Pavón [52] as well. Its study is one of the main achievements of their expeditions [53,54]. Among the species, C. micrantha is quite widespread in the Amazonian montane forests of central and southern Peru (Figure 8) in the thermo− and infratropical hyperhumid and ultra−hyperhumid bioclimatic zones with tree ferns (Cyathea) and palms (Iriartea deltoidea Ruiz & Pav.) [35]. C. pubescens Vahl ascends in central and northern Peru to the hyperhumid mesotropical belt (Supplementary Table  S1), also accompanied by tree ferns [37].
Tafalla and Manzanilla also collected Theobroma cacao L. and T. alba Ruiz & Pav. (= T. subincanum Mart.) and the palm Phytelephas macrocarpa in the Amazonian rainforests of central Peru, recording its use as food and materials. Unknowingly, they delved into the original area of the cocoa crop [55], in whose forests we find wild cocoa today [36]. Phytelephas macrocarpa is widespread, with uses such as those described in the expedition diaries, as the fruit is now used as food and for roofing [56].  Tafalla and Manzanilla also collected Theobroma cacao L. and T. alba Ruiz & Pav. (= T. subincanum Mart.) and the palm Phytelephas macrocarpa in the Amazonian rainforests of central Peru, recording its use as food and materials. Unknowingly, they delved into the original area of the cocoa crop [55], in whose forests we find wild cocoa today [36]. Phytelephas macrocarpa is widespread, with uses such as those described in the expedition diaries, as the fruit is now used as food and for roofing [56].

The First Ethnobotanical Expedition, Anthropology and Vegetation
One of the most interesting aspects of the expedition is that Ruiz, Pavón and Tafalla obtained ethnobotanical information on all of the vegetation types of Peru with their altitudinal distributions (Table 1). According to Schultes [57], Hipólito Ruiz became the great ethnobotanist of his time, since one of the functions assigned to him in Spain was to obtain the popular names and uses of the plants [13,18].
Although all of the unpublished and edited notes from the expedition recorded 2327 plants (Supplementary Table S4), about 5000 plants with uses are known today in Peru [58]. Few works have been written on the relationship between uses, anthropological aspects, bioactive compounds and the ecological (geographical) environments of the plants [59]. However, although the expedition initiated by Ruiz and Pavón ended two centuries ago, many of the habitats of that time still exist. It seems that Hipólito Ruiz's warning about the deterioration and preservation of the quina forests was heeded [53]. Galán de Mera et al. [59] have observed that in northern Peru, there is a relationship between the distribution of bioactive compounds of plants and bioclimatic belts, in such a way that alkaloids are typical of the lower bioclimatic belts, phenolic compounds, flavonoids and steroids are abundant in the meso− and supratropical belts, and iridoids reach the orotropical belt. The same observation can be made for plants from the expedition related to vegetation types (Table 2). Orotropical Valeriana pilosa Grasslands Iridoids [67] It is clear that the members of the expedition must have had contact with certain ethnic groups in Peru, especially in the eastern jungles (Figure 7). In the diaries published by Barreiro [14] and Jaramillo [16], indigenous communities were mentioned on numerous occasions, and the localities coincide with the mapped ancestral ethnic groups [38]. Table 3 shows the correspondence between some texts of the diaries, with the names applied to the indigenous people, the locality and the mapped ethnic group. The coincidences between the expedition's localities and the territories of the Pano, Arawaw and Jíbaro ethnic families are evident. For example, the collected specimens of Cinchona come from forests inhabited by these people. In the region of Pueblo Nuevo (Huánuco), in the surroundings of present-day Tingo María, we find one of the few places where the expedition reached the lowland Amazonian rainforest. Here live the Yaneshas, who still use the leaves of Phytelephas macrocarpa, just as they did in the time of Ruiz and Pavón. Uni and Cashibo−Cacataibo (43) B: diary by Barreiro; J: diary by Jaramillo. Words in bold and highlighted in gray signify the place in the text where native people appear. The numbers in brackets match with those in Figure 7.

Conclusions
The Spanish expedition to the Viceroyalty of Peru brought to light a great diversity of Peruvian plants. We have compiled 6493 specimens, of which 2327 are useful plants used by native indigenous people and would later serve as medicines in Lima or Spain, including some, such as the Cinchona tree or palm trees used in construction, Phytelephas macrocarpa or psycholeptics such as Psychotria tinctoria Ruiz & Pav. (= Palicourea tinctoria Schult.), whose uses and effects are still being studied in the 21st century.
With this work, we have described the plant communities where the RSBEVP studied many species, whether they had uses and which possible ethnic groups used them. For this, we have drawn up maps with the observation localities with their corresponding bioclimatology, observing the type of vegetation in their environment. Most of the plants collected or observed come from the thermo-and mesotropical bioclimatic belts, both from the eastern forests and from the Peruvian coast. In fact, the expedition studied species from all of the habitats of Peru, but those in the eastern rainforests were extensively collected due to the political interest in finding species of the genus Cinchona. It was precisely in these forests that they obtained most of the useful plants, so it seems that the knowledge of the Pano, Arawaw and Jíbaro ethnic families was very important.
From a taxonomic point of view, the genera most studied by Ruiz, Pavón and Tafalla include Cinchona, Erythroxylum, Nolana, Polylepis, Theobroma and Valeriana.
The study of the flora observed during past expeditions can provide a new method for carrying out new ethnobotanical research in areas close to the expedition itineraries and for analyzing and discovering new bioactive molecules.
It may even be possible to use the expedition routes as a tourist attraction and for the conservation of historic forests.
Supplementary Materials: The following supporting information can be downloaded at https: //www.mdpi.com/article/10.3390/biology12020294/s1. Table S1: Localities of the Spanish Royal Botanical Expedition to the Viceroyalty of Peru, with a representation of plants per locality, uses, altitude (H in m), mean annual temperature (T in • C), average maximum (M in • C) and minimum (m in • C) temperatures of the coldest month, thermicity index (It), annual precipitation (P in mm), and bioclimatic belt and ombrotype; Table S2: Cartographic resources consulted for Peruvian toponymies; Table S3: Species number per locality, decimal coordinates and altitudes of the localities of the Spanish Royal Botanical Expedition to the Viceroyalty of Peru; Table S4: Thermicity index (It), annual precipitation (P in mm) and number of plants with specific uses in the localities of the Spanish Royal Botanical Expedition to the Viceroyalty of Peru. References [68][69][70][71][72][73][74][75][76] are cited in the supplementary materials.