A new record of the Collared Ground Snake Atractus collaris Peracca, 1897 (Serpentes: Colubridae) in Brazilian Amazonia

-A new species of Atractus is described from the Atlantic Forest of the states of Sergipe and Alagoas, northeastern Brazil. It can be distinguished from other Atractus by the combination of a long loreal, temporal formula 1 + 2, 7 supralabials, dorsal scales in 15 rows, and a dorsal color pattern of small transverse brown bands on a reddish ground color. Comparisons are made with all other Atractus species with 15 dorsal scale rows, but the lack of data precludes the finding of its precise relationships. RESUMO.-Uma nova especie de Atractus e descrita para a regiao de Floresta Atlantica dos estados do Sergipe e Alagoas, do nordeste do Brasil. Pode ser distinguida das demais especies de Atractus pela combinacao de uma loreal longa, 7 supralabiais, formula temporal 1 + 2, 15 fileiras de escamas dorsais em volta do corpo, e um padrao de coloraqao dorsal composto por finas faixas transversais castanho sobre uma cor de fundo avermelhada. Comparacoes sao feitas com todas as demais especies de Atractus com 15 fileiras de escamas dorsais, mas a falta de dados impede uma definikao prescisa de suas relaoqes. l erpetology, Vol. 29, No. 3, p. 416-419, 1995 i t 1995 Society for the Study of Amph bians and Reptiles ecies of Snake in the Genus Atractus Herpetologically, the northeastern portion of Brazil (an area roughly defined by the states north of 15?S and east of 46?W) is poorly known. Recently, there have been several studies of the herpetofauna of interior regions of this area (e.g., Vanzolini, 1974, 1976; Vanzolini et al., 1980; Rodrigues, 1991). However, no comprehensive herpetological study has ever been made of the coastal region. Such a study is most urgent owing the rapid ongoing destruction of the Atlantic Forest. Although most Atlantic Forest snakes i all , the northeastern portion of a roughly defined by the states a d east of 46?W) is p orly known. e e ave been several studies of the a of interior regions of this area (e.g., have wide distributions, this pattern is not true of the species in the genus Atractus, most of hich have restricted ranges and are therefore more sensitive to human disturbance. Most species of Atractus are poorly represented in museum collections and, despite the efforts of Savag (1960) and Hoogmoed (1980), who dealt with small geographic regions, a complete revision is still needed. While examining A. reticulatus, I found some misidentified specimens that repr ent a new taxon, which I propose to call: 416 This content downloaded from 207.46.13.149 on Wed, 28 Sep 2016 04:13:01 UTC All use subject to http://about.jstor.org/terms NEW ATRACTUS FROM BRAZIL FIG. 1. Dorsal pattern of Atractus potschi. Atractus potschi sp. n. (Figs. 1 and 2) Holotype.-Instituto Butantan, IB 48438, an adult male from Maceio, State of Alagoas, Brazil, collected on 19 July 1985, by Adilton Jose do Santos. Paratypes.-Museu de Zoologia da Universidade de Sao Paulo, MZUSP 7196, an adult female, MZUSP 7001,7195,7197, adult males, from Salgado, State of Sergipe, Brazil, collected on 29 April 1978 by I.M. Freire; MZUSP 7275,7276, 7278, 7280, 7281, males, and MZUSP 7277 and 7279, females, from Salgado, State of Sergipe, Brazil, collected between September and November 1978 by I.M. Freire. Diagnosis.-An Atractus distinguished from all others by the combination of a long loreal, temporal formula 1 + 2, seven supralabials, 7-8 maxillary teeth, 15 scale rows around the body and a dorsal color pattern of small transverse brown bands on a reddish ground color (refer to Table 1 for diagnostic features to other Atractus species that likely occur at the same area). Description of the Holotype.-An adult male, snout-to-vent length (SVL) 255 mm; tail length 35 mm (13.7% of SVL); head length 9.6 mm (3.76% of SVL) from rostral to posterior tip of mandible, head width 7.0 mm (72.9% of head length) at broadest point; distance across eye 1.1 mm; snout length 3.0 mm (2.72 times distance across eye); head barely distinct from the body, rostral about 1.6 times broader than high; internasals as broad as long; prefrontals about 1.3 times broader than long; frontal as broad as FIG. 2. Holotype of Atractus potschi, IB 48438. Dorsal, lateral and ventral aspects of the head. l ng; parietals about 1.5 times longer than wide; nasal divided; loreal about 4.1 times longer than high; eye small, pupil round; postocular 2; temporals 1 + 2; supralabials 7, 3 and 4 contacting orbit; mental 1.7 times wider than long, separated from chinshields by the first pair of infralabials; infralabials 7, 1 to 4 contacting chinshields; anterior chinshields about twice as long as wide; posterior chinshields absent. Maxillary teeth 7. Dorsal scales in 15-15-15 rows, scales smooth without apical pits. Ventrals 147; anal single; paired subcaudals 35. Hemipenis extending to the level of the seventh subcaudal scale, bilobed, bifurcation occurring at the level of the sixth subcaudal. Variation (12 Specimens).-Maximum SVL 351 mm in females and 312 mm in males; tail length 8.6-11.7% (X = 9.9, s2 = 1.33, N = 3) of SVL in females and 8.8-14.7% (X = 13.0, s2 = 2.10, N = 9) in males. In MZUSP 7276, there are 8 supralabials on the right side, with 4 and 5 con5mm 417 This content downloaded from 207.46.13.149 on Wed, 28 Sep 2016 04:13:01 UTC All use subject to http://about.jstor.org/terms

ABSTRACTThe genus Elachistocleis comprises fossorial frogs distributed throughout Central and South America. Despite their wide distribution, species such as Elachistocleis helianneae Caramaschi, 2010 (Anura: Microhylidae) are poorly documented due to their cryptic behaviour. Here, we present the first record of E. helianneae for the western region of Pará state, in the central Brazilian Amazon. Four specimens (one juvenile and three adults) were collected during nocturnal surveys in temporary puddles along the BR‐163 highway between March and April 2022. Additionally, an updated distribution map of the species was created, incorporating this new record and data available in the literature. The new record fills a significant gap in the distribution of E. helianneae in the central Amazon, which previously spanned over a thousand kilometres. Our record is located approximately 590 km from the closest record to the west, in the state of Amazonas, and about 520 km from the nearest record to the east, in the state of Amapá. The Santarém record significantly improves our understanding of the distribution of E. helianneae, emphasising the importance of targeted surveys in underexplored habitats. Our findings highlight the importance of filling distributional gaps to enhance knowledge of amphibian biodiversity and inform conservation efforts.

Isoprene emission from plants accounts for about one third of annual global volatile organic compound emissions. The largest source of isoprene for the global atmosphere is the Amazon Basin. This study aimed to identify and quantify the isoprene emission and photosynthesis at different levels of light intensity and leaf temperature, in three phenological phases (young mature leaf, old mature leaf and senescent leaf) of Eschweilera coriacea (Matamatá verdadeira), the species with the widest distribution in the central Amazon. In situ photosynthesis and isoprene emission measurements showed that young mature leaf had the highest rates at all light intensities and leaf temperatures. Additionally, it was observed that isoprene emission capacity (Es) changed considerably over different leaf ages. This suggests that aging leads to a reduction of both leaf photosynthetic activity and isoprene production and emission. The algorithm of Guenther et al. (1999) provided good fits to the data when incident light was varied, however differences among E S of all leaf ages influenced on quantic yield predicted by model. When leaf temperature was varied, algorithm prediction was not satisfactory for temperature higher than ~40 °C; this could be because our data did not show isoprene temperature optimum up to 45 °C. Our results are consistent with the hypothesis of the isoprene functional role in protecting plants from high temperatures and highlight the need to include leaf phenology effects in isoprene emission models.

We studied a specialised assemblage of sand-dwelling fish species from a streamlet in central Amazonia. The five sanddwelling species comprised 15.2 % of the total number in the streamlet (33 species). Two of the sand-dwellers are daytime foragers, Characidium cf. pteroides (Crenuchidae) and Stauroglanis gouldingi (Trichomycteridae), whereas three ones are night-time foragers, Gymnorhamphichthys rondoni (Rhamphichthyidae), "Imparfinis" pristos and Mastiglanis asopos (Heptapteridae). With the exception of C. cf. pteroides, the remainder species bury in the sand during their resting period. All five species bear a cryptic, sand-colour pattern, and some are translucent, traits which we regard as advantageous both for evasion from predators and for approaching prey (for the daytime foragers). All five species are microphagous carnivores and their foraging tactics range from generalised sit-and-wait (C. cf. pteroides) to active searching for interstitial prey (G. rondoni). A unique "drift-trap" system made up by the extended barbels and filamentous first pectoral-fin rays is employed by M. asopos. We regard the small size and low number of vertebrae (which is functionally expressed by fast displacements in the sand) as additional features advantageous to explore the sand habitat, allowing diving quickly in the substrate to evade predators and to forage for small prey in sand interstices or plant debris. The relationship between morphological and behavioural characters suited to life in sandy substrates is examined under the perspective of the current phylogenies for each group of psammophilous fishes here studied. The mapping of these characters demonstrates that not all of them evolved specifically for strict psammophily. Instead, some of them may represent the final step of a transformation series or synapomorphies of higher hierarchical levels. Several characters linked to psammophily, such as small body, large eyes, and scarce pigmentation are probably paedomorphic traits. We consider that the little variable specific composition of fish sand-dwelling assemblages and the wide (although patchy) geographical distribution of their species in the Amazon are due to the widespread occurrence and low complexity of this specialised habitat. The pre-existence of benthic habits, small size, and the broad distribution of rivers with sandy beds, mainly in the Amazon and Orinoco basins, possibly played a determinant role in the origin and diversification of psammophilous assemblages among freshwater fishes in South America.

The Guiana Shield harbours one of the best preserved and largest extents of tropical forest on Earth and an immense biodiversity. The herpetofauna of this region remains poorly known. The species-rich snake genus Atractus contains ∼140 species, many with complicated taxonomic histories, including A. schach. Examination of specimens in museums and newly collected material from French Guiana has allowed the illustration of hemipenial morphology for the first time and an expanded diagnosis. Concatenated molecular phylogenetic (mitochondrial and nuclear genes) and phenotypic (morphometrics, external and hemipenial morphology) analyses confirm non-monophyly of the A. flammigerus group and indicate that A. schach is a species complex with three new species described here. The geographic distribution of A. schach sensu stricto is restricted to Guiana, Surinam, and French Guiana north of Tumucumaque massif. Populations tentatively assigned to A. schach from the east from French Guiana in the Roura lowlands to Almeirim, and from central Amazonia between the Negro and Trombetas rivers in Brazil are also recognized as new species. Our results suggest that populations from south of the Amazon River are not conspecific with those from the Guiana Shield.http://www.zoobank.org/urn:lsid:zoobank.org:pub:A7AE40BC-4716-4302-B3BE-1F43600B0A72

Encyclia is a neotropical orchid genus distributed from Florida to South Brazil and comprises ~120 taxa, including Encyclia mapuerae (Huber) Brade & Pabst. Besides its diversity and wide distribution, conclusive data on pollinators and reproductive biology of this orchid genus is scarce. Furthermore, nothing is known about the production of floral reward in Encyclia but the pollinators of their species are assumed to be attracted through food deception. Based on data on phenology, floral morpho-anatomy, histochemistry, pollinators, pollination mechanisms, and breeding system, the reproductive biology of E. mapuerae was studied in a nature reserve at Central Amazonia, Brazil. The flowers of E. mapuerae show longitudinal lines on the labellum that act as a nectar guide. The secretory epidermis has papillae whose cells are covered by an ornamented cuticle. The subtended tissue is composed of a tree-layered collenchyma. The flowers attract several species of Hymenoptera. However, a single species of Centris was recorded as pollinator. The bees collect the nectar produced inside the cuniculus. When the bees leave the flower the pollinarium is attached to their heads. Encyclia mapuerae is self-compatible and pollinator-dependent. The reproductive success in natural conditions is low because of deficient pollen transference due to the scarcity of pollinators. As far we know this is the first study that reports and production of floral reward in Encyclia. This discovery provides new insights on the function of the cuniculus in Laeliinae, and sheds light on the evolution of floral rewards and pollination mechanisms within this diverse group of Neotropical orchids.

-A11 species of diurnal leaf-litter anurans in central Amazonia changed the type and size of their prey as they grew. Postmetamorphic individuals of all species ate principally mites and collembolans, and larger frogs ate larger prey of types. The shift in prey types was not a passive effect of selection for larger prey. There was a strong relationship between electivity for prey types and frog size, independent of electivities for prey size, in six of the seven species. This study showed that most species in the community had strong ontogenetic changes in diet composition and electivity for prey types, and these changes did not conform to simple models of the effects of predator size and diet quality. urnal of Herpetology, Vol. 32, No. 3, pp. 392-399, 1998 pyright 1998 Society for the Study of Amphibians and Reptiles e Ef ects of Size on the Di ts of Six Sympatric Spec es of stmetamorphic Litter Anurans in Ce tral Am zonia Change in diet with ontogeny has often been studied in fish (reviewed in Werner and Gilliam, 1984; Osenberg et al., 1992; Sheldon and Meffe, 1993). In anurans and reptiles, change in diet has been related to changes in selection for the type or size of prey (Schoener and Gorman, 1968; Pengilley, 1971; Labanick, 1976; Rose, 1976; Mushinsky et al., 1982; Christian, 1982; Dominguez and Salvador, 1990; Donnelly, 1991; Simon and Toft, 1991; Lima and Moreira, 1993). However, most of these studies have focused on one or two species (Lynch, 1985 is an exception). Consequently, little is know about change in diet with ontogeny in multi-species assemblages. However, the selection for prey size is not independent of selection for prey type because different types of arthropods have different mean sizes. The smallest arthropods available for anurans and lizards are principally mites and collembolans. The most abundant arthropods of intermediate sizes are ants, termites, and beetles, and the largest arthropods are orthopterans, butterflies, and spiders (Schoener and Janzen, 1968; Dominguez and Salvador, 1990; Lima and Moreira, 1993). Therefore, variiet ith ontogeny has often be n is (revie ed in Werner and Gilliam, et al., 1992; Sheldon and Mef e, a s and reptiles, change in diet late to changes in selection for the i prey (Schoener and Gorman, ille , 1971; Labanick, 1976; Rose, i s et al., 1982; Christian, 1982; a Salvador, 1990; Donnelly, 19 1; t, 1991; Li a and Moreira, 19 3). st of these studies have focused on s ecies (Lynch, 1985 is an exception). l , little is know about change in diet i ulti-species as emblages. e selection for prey size is not inselection for prey type because es of arthropods have dif erent . e s al est arthropods available s a lizards are principally mites ation in the taxonomic composition of the diet with the stage of growth of individuals is expected as a passive side effect of the capacity to ingest larger prey. Lima and Moreira (1993) d monstrated that the shift in prey types with growth was not just a passive effect of selection for larger prey in the leaf-litter frog, Colostethus stepheni. For that species, there was a strong relationship between electivity for prey types and frog size, independent of electivities for prey size. To test whether size-independent shifts in electivity are a general phenomenon in leaf-litter frogs or are restricted to C. stepheni, I studied the diet of postmetamorphic individuals of six species of diurnal leaf-litter frogs that occur syntopically with C. stepheni in Reserva Florestal Adolpho Ducke in Central Amaz6nia. MATERIALS AND METHODS Study Area and Distribution of the Species.-The study was conducted in a 10,000-ha tropical rainforest reserve, Reserva Florestal Adolfo Ducke (Reserva Ducke), located 25 km northeast of Manaus, Amazonas, Brazil (03?08'S; ion in the tax nomic composition of the diet ith the stage of growth of in ividuals is excted as a passive side ffect of the capacity to est larger prey. Lima and Moreira (1993) e onstrated that the sh ft in prey types with o th was not just passive effect of selection larger prey in the leaf-litter fr g, Colostethus pheni. For that sp cies, there was a st ong reionship between electivity for prey types and g size, ind pendent of electivities for prey 392 This content downloaded from 157.55.39.96 on Sun, 02 Oct 2016 05:58:51 UTC All use subject to http://about.jstor.org/terms DIETS OF SIX LITTER FROGS 60?04'W). The study was done at two sites separated by four km. The first site, described by Lima and Moreira (1993) lies along six trails (?7 km) in an undisturbed part of Reserva Ducke. The second site included a plateau and stream. I used an area of about 2 km by 200 m wide along the margins of the stream and about 2 km by 10 m on the plateau. The plateau is traversed by an unsealed forest road. Temporary pools form on the margins of the road in the rainy season. The community of diurnal leaf-litter frogs of Reserva Ducke is composed of seven species: Adenomera andreae and Eleutherodactylus fenestratus (Leptodactylidae), Colostethus marchesianus, Colostethus stepheni, and Epipedobates femoralis (Dendrobatidae), and Bufo cf. typhonius and Dendrophryniscus minutus (Bufonidae). The juveniles of all species metamorphose at ca. 6.5 mm snout-urostyle length (SUL), except for E. femoralis and E. fenestratus, which metamorphose at >8.0 mm SUL. Individuals of Eleutherodactylus fenestratus >24 mm are nocturnal. All species are active during the day and can be found in the same place foraging for arthropods over the leaf-litter. At both study sites, five of the species (D. minutus, C. marchesianus, E. fenestratus, A. andreae, and B. cf. typhonius), are usually found near streams, especially in the dry season. In the rainy season, those species have wide distributions and may be found on valleys, slopes, and plateaus. Epipedobates femoralis occurred only on the plateau in the second site in both the rainy and dry seasons. Food Availability.-All species forage principally on the surface of the litter. However, litter arthropods migrate between the surface and the first few centimeters of litter depending on climatic conditions. The pool of invertebrates generally available was estimated from samples of litter and soil to a depth of 5 cm, collected with a 6.4 x 6.6 cm soil corer. A total of 144 samples were collected from February 1991 to March 1992 (except September and October 1991). The invertebrates were extracted in Berlese funnels for eight days and identified to order or family. The samples were collected at different points distributed throughout the length of each trail in each month so that all areas in which frogs were collected or observed were sampled. There was little variation in the proportion of prey types in samples of availability throughout the year. Therefore, arthropod availability used in analyses of electivity was based on the pooled sample for the whole year. The extraction of invertebrates from litter samples using Berlese funnels, when not done with care, could sample 10% or less of mites and collembolans in the sample (Toft and Levings, 1979). In this study, extractions were done slowly and carefully, and mites constituted 65% of the fauna and collembolans 28%, proportions similar to those encountered in detailed studies (Simon and Toft, 1991). Analyses of Diet.-A total of 1065 frogs were used for the diet analyses. Approximately 20% of these were collected during 2-3 d periods each month from April 1988 to October 1989 (except June and July 1989) and about 60% were collected from January 1991 to March 1992. I walked all trails in both areas, capturing every frog within one meter of the center of the trail between 0800h and 1700h. The remainder of the nimals wer collected from March 1993 to May 1995. During that period, I walked all trails capturing only fr gs in ize classes that were lacking from the origi al collections. The animals were killed immediately and fixed in 10% formalin. Their lengths, from the tip of the snout o the posterior end of the urostyle (SUL), were measured with Vernier callipers after preservation. For ana yses of di t, I used only items in the stomach. They were sorted into prey categories (generally orders or family). Prey categories that contributed less than 10% (mass) of the diet of all size ca egories were grouped as other invertebr tes or larvae, For analyses of electivity, I considered only seven prey categories (Collembola, Acarina, Formicidae, COA, Isoptera, insect larv e, and invertebrates). The COA category included Coleoptera, Orth ptera, and Ar neae. Those categories were combined based on the supposition that sit-andwait foragers will be more efficient in capture of mobile species of those prey types (Huey and Pianka, 1981; Toft, 1985; Pough and Taigen, 1990). I d d not group this category with other invert rates, because it may contain important independent information about the diet composition of the species. Sizes of prey were measured under a dissecting microscope with a gridded eyepiece. In the case of disarticulated items, the original size of the prey was estimated by comparison with a reference collection. Wet masses (excess water removed with blotting paper) of the preserved animals were determined on a digital balance accurate to 0.0001 g. I estimated the masses of animals that were lighter than the limit of reading of the balance by grouping 10-100 preserved arthropods of similar size from the same taxon, weighing them, and calculating the mean mass. Statistical Analyses.-Electivities were based on numbers of individuals rather than mass and calculated by the method of Jacobs (1974): D = (Rk Pk)/[(Rk + Pk)(2RkPk)], where Rk is the proportion of prey k in the stomach contents and Pk is the proportion of prey k 393 This content downloaded from 157.55.39.96 on Sun, 02 Oct 2016 05:58:51 UTC All use subject to http://about.jstor.org/terms

ABSTRACTThe Leptodactylus pentadactylus species group is comprised of medium to large species of Neotropical frogs. Leptodactylus knudseni, a member of this species group, has a wide distribution throughout the Amazon Basin. Herein we describe aspects of the reproductive biology of L. knudseni and provide notes about the ontogenetic variation of its tadpoles based on a population in a non-flooded forest near Manaus, Amazonian Brazil. Amplectant pairs of L. knudseni lay foam nests in excavated basins on the edge of temporary ponds located on clay soil and at least 50 m from a stream. The tadpole development happens initially in the foam nests with access to the pond after the rain flooding the basins. Studied clutches lacked trophic eggs and tadpoles did not produce foam. Ontogenetic variations in L. knudseni tadpoles are related to size, teeth formulae and body colour. The use of excavated basins for the deposition of foam nests has been reported in several species of the L. pentadactylus group. The absence of trophic eggs and production of foam by the tadpoles differ from other species of the L. pentadactylus group. The tadpole morphology is similar to that described for other species of the group.

Gymnophthalmus represents a challenging group for systematics of microteiid lizards. Due to scarcity of exemplars and molecular data, the taxonomy of the genus has been unstable, and six of its eight species are considered part of a poorly-delimited complex of unisexual and bisexual species. Unnamed populations of red-tailed Gymnophthalmus from savanna enclaves in Amazon, similar to G. vanzoi but with differences in color pattern, have been noted in the literature. Here, we used molecular and morphological data to test the taxonomic status of the Central Amazonian red-tailed Gymnophthalmus (G. sp.). Our molecular analysis recovered a close relationship between G. vanzoi and G. sp. from Central Amazon, with minimal divergence. Samples were similar in scale counts but presented significant variation in color pattern and morphometry. Despite the geographic isolation, individuals of both populations cannot be fully differentiated based on morphology. Thus, our results suggest that G. vanzoi has a wider distribution, including the Central Amazonian red-tailed Gymnophthalmus and likely morphologically similar populations from other enclaves of Amazonian savannas, which may have been isolated recently. Based on our comparative analysis, we highlight some characters proved useful for differentiating Brazilian Gymnophthalmus and discuss some prospects for the taxonomy of the genus.

Most species of Amazonian snakes have wide geographic distributions. However, local environmental factors influence the formation of assemblages in different localities. In this study, we investigated the composition of the assemblage and the effect of environmental variables on the distribution of the species inhabiting an upland forest in the Experimental Farm area of the Federal University of Amazonas in Manaus, Brazil. Data collection was carried out in 24 standardized plots. Each plot was sampled four times between July 2015 and April 2017 by active search method. We recorded 83 individuals from 29 species belonging to six families. The richness in the study area corresponded to 78% of the snake species and 100% of the families previously recorded for Manaus. As observed in other localities, the most abundant species was the Amazonian lancehead (Bothrops atrox). Multiple linear regression models did not detect any effect of environmental variables on species richness and abundance of individuals. However, quadratic polynomial regression models revealed that intermediate canopy opening percentages positively influence the richness and abundance of snakes. It is possible that the result is related to a tradeoff between the thermoregulation behavior of these animals and to their susceptibility to predation.

Study of rough notes and sketches made by D.C. Geijskes in 1972 and the recently found original drawings by E. de Selys Longchamps done in 1884 from the male syntype of Neoneura bilinearis Selys, 1860, shows the syntype male and female (now lost for several decades) of N. bilinearis refer to the same species later described as Neoneura gaida Rácenis, 1953. Therefore N. gaida is considered a junior synonym of N. bilinearis Selys, 1860. A neotype is chosen for the true N. bilinearis (neotype ?, Suriname, Kabalebo, 15 viii 1965, in RMNH). N. bilinearis sensu Williamson (1917) is redescribed as Neoneura confundens sp. nov. (holotype ?, Suriname, Jodensavanna, Koela-kreek, 13 ii 1946, in RMNH). N. confundens has a wide distribution in South America north of the Tropic of Capricorn, but it is lacking from the central and lower Amazon. It occurs in several color morphs and also varies in male appendage, genital ligula, and female pronotum morphology.

One economically promising Amazonian species is camu-camu (Myrciaria dubia) which fruits have the highest content of vitamin C recorded, with a high potential for applications on the food, supplement and cosmetic industry and which can be a cornerstone for agroforestry initiatives for Amazonian peasants. Camu-camu has an Amazon wide distribution although most studies and collections have occurred on the Central and Western Amazon. The aim of this study is to assess the distribution and potential vulnerability of camu-camu populations in the state of Rondônia, Brazil, the southern limit of its distribution, which exhibit a drier climate. We use data recorded in herbaria and a bioprospecting expedition and data on anthopogenic stressors, estratified at the municipal level, like fire events, deforestation and dams. Camu-camu records occur preferentially in the Central and Northern part of the state, however most of the collections are around cities, major rivers and roads, showing a strong collector bias. Municipalities with camu-camu records suffered higher rates of deforestation and show higher occurrence of fire events and planned dams than municipalities without camu-camu records. Camu-camu populations in Rondônia are thriving on drier conditions and may be more adapted for future prevalent conditions for the Amazon under climate change. These adaptations may be useful for future domestication efforts. We call for an increasing effort of collecting and salvaging camu-camu populations on human dominated landscapes and to encourage participatory conservation with local farmers, for an ex-situ conservation on rural landscapes, especially under the prospect of climate change.

A new species of Atractus is described from upper Cururu River in the Amazon Basin of Brazil. The new species differs from all currently recognized Atractus by having a dorsal colour pattern reddish brown, with first two dorsal scale rows creamish white, hemipenis slightly bilobed, with alary spines at intrasulcar region, and lateral projections of the lobes depressed in their basal portions. In addition, a discussion concerning putative close relative taxa is provided.

The flora of the southern Surinam savannas (not completely known but probably so for the greater part) consists of 314 species collected so far. Ten of these were not found in any other region, 6 belong to the southern Guianan element, 14 to the Guianan element, the rest have a wider distribution. Fourty of the species occur in this region on the northern limit of their area and 18 of these even reach their northernmost station here. Among the 290 species collected on savannas in central Amazonia 82 species were found also on the savannas of southern Surinam. Northern Surinam, with a total of 288 recorded savanna species, has 183 species in common with southern Surinam. This floristic contrast can be correlated for about half of the differentiating species with ecological or geographic factors. The geographic spectra of the two regions are greatly similar.