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Des études paléoenvironnementales antérieures ont montré que des changements majeurs de la végétation et de l’environnement se sont produits en Afrique centrale à partir de l’Holocène moyen (ex. Maley & Brenac 1998). Plusieurs d’entre elles mettent en évidence une origine humaine et supposent que les grandes migrations de population, les innovations techniques (par exemple, la technologie de la fonte du fer) et/ou de nouveaux choix dans les pratiques agricoles, conduisant à la déforestation et au défrichement, sont les moteurs de ces changements. Cependant, à ce stade, l’absence de reconstitution démographique ne permet pas de soutenir pleinement ces hypothèses. Notre étude utilise une base de données archéologiques géoréférencées pour déduire la dynamique des populations et l’évolution des pratiques culturelles en Afrique centrale occidentale au cours des 5000 dernières années. Cette base de données comprend 1139 dates calibrées au 14C provenant de 425 sites – localisés dans le sud du Cameroun, au Gabon, en République du Congo, en Guinée équatoriale et dans la partie occidentale de la République démocratique du Congo –, remontant à un maximum de 5000 ans cal. BP. La modélisation des données indique une possible croissance de la population entre ~2500 et ~1500 ans cal. BP, coïncidant avec l’apparition à l’échelle régionale de techniques et de pratiques spécifiques. L’augmentation concomitante des fosses dépotoirs, des vestiges d’utilisation de palmier à huile Elaeis guineesis, l’apparition de rares restes de millet Pennisetum glaucum et la montée en puissance des vestiges de métallurgie du fer ont eu lieu pendant la seconde moitié du Néolithique, à partir d’environ 2800 ans cal. BP. Dans les régions côtières, la croissance de la population concerne le Néolithique et le début de l’âge du fer (2500-2000 ans cal. BP et 2000-1500 ans cal. BP), tandis que dans l’Hinterland cette croissance semble légèrement plus tardive (2400 et 1300 ans cal. BP). Il n’est pas possible d’identifier un phénomène commun de diffusion à partir d’un seul centre. Les innovations techniques et les nouvelles pratiques semblent plutôt s’être répandues à travers un large réseau d’interactions culturelles qui a favorisé la formation des sociétés d’Afrique centrale occidentale au cours du troisième millénaire avant notre ère. Palaeocological studies show that major vegetation and environmental changes occurred in Central Africa from the mid-Holocene (e.g. Maley & Brenac 1998). Several suggest a human origin and assume that large population migration, technical innovations (e.g. iron-smelting technology) and/or change in agricultural practice, leading to deforestation and land clearance, are the drivers of these changes. However, at this stage, the lack of demographic reconstruction does not fully support these hypotheses. Here, a georeferenced archaeological database is used to infer population dynamics and the evolution of cultural practices in Western Central Africa over the last 5000 years. This database includes 1139 14C calibrated dates from 425 sites throughout southern Cameroon, Gabon, the Republic of Congo, Equatorial Guinea and the western part of the Democratic Republic of Congo, dating back a maximum of 5000 cal. yr BP. Data modelling indicate possible population growth from 2500 to 1500 cal. yr BP, coinciding with the occurrence at a regional scale of specific techniques and practices. The concomitant increase of refuse pits, palm oil Elaeis guineesis and iron metallurgy (plus rare remains of millet Pennisetum glaucum) took place during the second half of the Neolithic, beginning around 2800 cal. yr BP. In the coastal regions, the population growth concerns the Neolithic and the Early Iron Age (2500–2000 cal. yr BP and 2000–1500 cal. yr BP), while in the Hinterland population growth seems slightly later (2400 and 1300 cal. yr BP). It is not possible to identify a common diffusion phenomenon from a single homeland. Rather, technical innovations and new practices appear to have spread through a wide network of cultural interactions, which fostered the formation of Western Central African societies during the third millennium.

We present new Gabonese locality records, ecological and morphological data or unpublished material for Kinixys erosa (Testudinidae), Trachylepis albilabris (Scincidae), Calabaria reinhardtii (Boidae), Dasypeltis fasciata, Hapsidophrys smaragdinus, Philothamnus carinatus, P. heterodermus and P. nitidus nitidus, Thrasops flavigularis,Toxicodryas blandingii and T. pulverulenta (Colubridae), Dendroaspis jamesoni jamesoni,Naja melanoleuca (Elapidae), Mehelya poensis, Polemon collaris (Lamprophiidae), Natriciteres fuliginoides (Natricidae), Python sebae (Pythonidae), Bitis gabonica and Causus maculatus (Viperidae). One snake species is newly recorded from Loango National Park, and three from Estuaire Province.

Le sauvetage archéologique du site de Dibamba Yassa, à l’entrée de la ville de Douala (Cameroun), par une équipe franco-camerounaise conduite par l’Institut de Recherche pour le Développement (IRD), a mis au jour plus de 20 000 tessons de poterie. Ils ont permis de définir cinq traditions céramiques se succédant sur 2 500 ans dans une région encore inconnue des archéologues. Le cadre chrono-stylistique, que les résultats permettent de construire, ouvre des possibilités de réflexions nouvelles sur l’histoire des interactions culturelles en Afrique centrale atlantique depuis le début de l’âge du fer ancien. Par ailleurs, la répartition spatiale des structures archéologiques suggère la possible apparition de villages-rues dès le début de la séquence chronologique. The archaeological rescue of Dibamba Yassa at the entrance to the city of Douala (Cameroon), by a Franco-Cameroonian team led by the IRD, uncovered more than 20,000 sherds of pottery allowing the definition of five successive ceramic traditions over 2,500 years, in a region still little-known to archaeologists. The chrono-stylistic framework that these results allow us to reconstruct opens up new possibilities for reflection on the history of cultural interactions in Central Africa since the beginning of the Early Iron Age. Finally, the spatial distribution of archaeological structures suggests the possible appearance of street villages at the beginning of the chronological sequence.

International Symposium, Ulsan, KOR, -; Rock engravings represent a particularly rich and moving dimension of prehistory. They seem to constitute one of the first, frustrated and clumsy scriptures that man in his desire to express himself, has entrusted to the rock in an eternal message. These petroglyphs thus represents a kind of documentary film on the spiritual aspirations of prehistoric peoples. We will present the rock art within the regional framework peculiar to West Central Africa and then discuss the rock engravings of the valley of Ogooué. We will explain how the rock engravings contributed to the classification of the Lopé National Park as a World Heritage Site.

An update is provided of current knowledge of the herpetofauna and batrachofauna recorded from caves in Gabon, western Equatorial Africa. No systematic field survey of reptiles and amphibians in Gabonese cave environments has yet been made, and data are available for only 19 (complexes of) caves. This compilation of published records and new observations includes seven reptile and at least nine amphibian species. None of them is restricted to cave environments, and most of the species are adaptable ecologically, being known from pristine as well as from highly degraded environments. All of them can be regarded as trogloxenes. Dedicated surveys, using appropriate methods, will certainly increase this species list considerably.

Aphyosemion flavocyaneum Chirio, Legros & Agn��se sp. nov. urn:lsid:zoobank.org:act: 1C559D3D-38A3-4322- A 7CF-BEBC547D4D8D Fig. 4 A���D, Table 3 Etymology The specific epithet refers to the main colours of this species (blue and yellow). Material examined Holotype GABON: adult ���, 32.3 mm SL (43.2 mm TL), Lake Ndaminz�� 0.42874 S, 9.54502 E, 115 m a.s.l., field reference code CHRSP1 - Lac Ndaminz��, 13 Apr. 2014, Laurent Chirio leg. (MRAC 2016-019 -P-1). Paratypes GABON: 3 ������, 6 ♀♀, 21.3 ���27.5 mm SL, same collection data as for holotype (MRAC 2016-019-P- 2���10). Differential diagnosis Distinguished from other species of Chromaphyosemion by its blue anal fin with no submarginal red band (vs species with a submarginal red band present), except for A. poliaki, and very rare specimens of A. melanogaster and A. malumbresi. Differs from the latter species through a combination of the following features: flanks and venter yellow-orange with no red punctuation (vs flanks bronze, venter brown-orange, regular red dots; flanks yellow-green, venter yellow-green with a black zone, irregular lines of red dots; flanks bluish-white, venter bluish with a black zone, regular red dots), blue iridescent scales on the ventral region close to the caudal peduncle (vs red scales or black scales), black alpha-shaped mark on the pre- and post-opercular region (vs no alpha-shaped mark, only a few red macules), anal fin blue with an orange portion on the basal region with no punctuation except black dots on basal and/or posterobasal portions (vs anal fin blue-green with many red dots; yellow-green with red dots; bluish-white with red dots). Colouration of live males (Fig. 4A ) FLANKS AND VENTER. Yellow-orange with no red punctuation, two greyish lateral stripes on ventral region close to caudal peduncle with some blue iridescent scales. Two rows of paradorsal golden scales in dorsal region from operculum to caudal peduncle with few black macules. HEAD. Yellow-orange. Premaxilla and mandible yellow-orange with black lower lips, orange infraorbital region with black macule, orange post-orbital region with two black macules, yellow-orange pre-opercle with two black macules, yellow-orange opercle with two black macules; black macules on pre- and postopercular region reveal an alpha-shaped mark. FINS. The dorsal fin is blue, but more orange near the insertion of the fin, and rows of black dots between rays. Anal fin blue with orange portion on basal region of fin, with no punctuation and no submarginal or marginal bands. Certain individuals may have some small black dots on basal region. Caudal fin blue with many carmine red dots and some carmine red streaks in upper and lower lobes; submarginal and marginal red bands absent. Acumens at apex of unpaired fins orange or white for dorsal fin, very short blue acumen for anal fin, and orange or white for caudal fin. Colour pattern of pelvic fins identical to anal fin with blue background and no submarginal band or marginal band. Pectoral fins translucent. Colouration of live females (Fig. 4B) FLANKS AND VENTER. Pale brown, four lines of red dots from opercle to caudal peduncle, two greyish lateral stripes, venter yellow-green, white on basal portion. Two rows of paradorsal golden scales in dorsal region, from operculum to caudal peduncle with red dots. HEAD. Premaxilla brown, mandible pale orange with black lower lips, brown supraorbital region, white infraorbital region with red macule, grey postorbital region with two macules, white pre-opercle, yelloworange opercle with one red dot. FINS. Dorsal fin yellow-green, rows of red dots between rays. Anal fin yellow-green with rows of red dots between rays. Caudal fin yellow-green, blue-green on distal portion, with rows of red dots between rays. Pelvic fins translucent with yellow-green reflection, red dots, blue reflection on edges. Pectoral fins are translucent. Colouration of ethanol-preserved males and females (Fig. 4 C���D) FLANKS AND VENTER. Flanks of males grey-yellow with three short lines of red dots, venter grey-yellow with no red punctuation. Two rows of paradorsal red scales in brown dorsal region from operculum to caudal peduncle. Flanks of females grey-yellow, three lines of red dots from the opercle to the caudal peduncle. Two rows of paradorsal red scales in the brown dorsal region, from the operculum to the caudal peduncle. HEAD. Premaxilla and mandible of male grey with black lower lips, infraorbital region has red macule, opercle with one red macule; very dark macules in post-opercular region. Head of female with a black lower lips, infraorbital region with a red macule. Head of female with black lower lips, infraorbital region with red macule. FINS. Male dorsal fin grey-blue with rows of red dots between rays. Anal fin grey-blue with some small red dots in posterobasal region. Caudal fin grey-blue with many red dots and some carmine red streaks in upper and lower lobes. Female dorsal fin greyish, with rows of red dots between rays. Anal fin greyish, with rows of red dots between rays. Caudal fin greyish, with rows of red dots between rays. Distribution and habitat This species has been found at seven localities (for three of them, specimens have not been studied or deposited in a museum) in the Awagn�� River Basin (Table 1, Fig. 1), has never been found elsewhere and seems to be endemic to this hydrographic basin. It lives in small, secondary rivers and small, forest streams, often with a sandy bottom, where it can be found along the riverbanks. It hides quickly in water plants or dead leaves. In one locality, the bottom is muddy, the water quite stagnant and some fish have even been observed in small water holes. The uppermost locality is Lake Ndaminz��, which is about 1 km long: the species was found only under the shadow of large trees, hidden in the roots near the banks. This species was found in syntopy with an undescribed species of Aphyosemion and an undescribed species of Epiplatys. At one single locality in the Mbomba River, a tributary of the Awagn�� River, it was found in syntopy with Poropanchax stigmatopygus (Wildekamp & Malumbres, 2004)., Published as part of Agn��se, Jean-Fran��ois, Chirio, Laurent, Legros, Olivier, Oslisly, Richard & Bh��, Herv�� Mv��, 2018, Unexpected discovery of six new species of Aphyosemion (Cyprinodontiformes, Aplocheilidae) in the Wonga-Wongu�� Presidential Reserve in Gabon, pp. 1-28 in European Journal of Taxonomy 471 on pages 9-12, DOI: 10.5852/ejt.2018.471, http://zenodo.org/record/3825049

Identification key of the Aphyosemion alpha group species 1. Anal fin without punctuation............................................................................................................. 2 ��� Anal fin with punctuation of black or red dots.................................................................................. 3 2. Flanks orange and bluish, ventral region orange, very intense orange portion between the end of the anal fin and the caudal peduncle, head highly red-orange.................................................................................................................................................. A. rubrogaster Chirio, Legros & Agn��se sp. nov. ��� Flanks beige, ventral region orange or beige, blue iridescent scales between the end of the anal fin and the caudal peduncle..................................................................................................................... 4 ��� Flanks blue or purplish blue, ventral region orange or bluish white, blue iridescent scales between the end of the anal fin and the caudal peduncle................................................................................. 5 3. Anal fin with some red carmine macules, mauve on basal portion, orange on median portion, a yellowish portion near the submarginal band, red and regular submarginal band, blue marginal band, orange little acumen............................................ A. barakoniense Chirio, Legros & Agn��se sp. nov. ��� Anal fin blue with orange portion on basal region, without punctuation except black dots on basal and/or postero-basal portions, without submarginal and marginal bands. Some individuals may have some small black dots instead of the submarginal band................................................................................................................................................. A. flavocyaneum Chirio, Legros & Agn��se sp. nov. 4. Two orange zones: orange portion on the opercle, venter beige with an orange portion above the pelvic fins, anal fin orange, blue near the basal portion and near the red submarginal band, dorsal fin orange, caudal fin blue with begin of upper and lower lobes light orange......................................................................... A. pusillum Chirio, Legros & Agn��se sp. nov. ��� No delimited orange zone, opercle orange, ventral region entirely orange, anal fin orange with a blue zone upper the red submarginal band, dorsal fin blue with large orange zone on rays, caudal fin blue with an orange caudal peduncle.......................... A. aurantiacum Chirio, Legros & Agn��se sp. nov. 5. Dorsal fin brown-orange, greenish on basal portion, red dots between rays, little orange apex, caudal fin light blue, some red dots on basal region, very long red streaks on distal region, red and irregular submarginal band, blue marginal band, little acumens light orange, flanks blue, ventral region orange................................................................................................................ A. alpha Huber, 1998 ��� Dorsal fin blue, orange distal portion near the apex, black dots between rays, very long orange acumen on the apex, caudal fin blue with orange portion on peduncle region, some red dots on basal region, very long red streaks on distal region, red and irregular submarginal band, blue marginal band, acumen orange very intense, flanks purplish blue, ventral region bluish white................................................................... A. flammulatum Chirio, Legros & Agn��se sp. nov., Published as part of Agn��se, Jean-Fran��ois, Chirio, Laurent, Legros, Olivier, Oslisly, Richard & Bh��, Herv�� Mv��, 2018, Unexpected discovery of six new species of Aphyosemion (Cyprinodontiformes, Aplocheilidae) in the Wonga-Wongu�� Presidential Reserve in Gabon, pp. 1-28 in European Journal of Taxonomy 471 on pages 25-26, DOI: 10.5852/ejt.2018.471, http://zenodo.org/record/3825049

Aphyosemion rubrogaster Chirio, Legros & Agn��se sp. nov. urn:lsid:zoobank.org:act: 1778A417-0D05-4C16-BE75-00B6DE36398C Fig. 6 E���H, Table 8 Etymology The specific epithet refers to the colour of the ventral region of this species (red). Material examined Holotype GABON: adult ���, 25.2 mm SL (31.3 mm TL), bridge on Nieng�� River, 0.65524 S, 9.57355 E, 61 m a.s.l., field reference code CHRSP6 - Niengu��, 4 Jul. 2014, Laurent Chirio leg. (MRAC 2016-019 -P-93). Paratypes GABON: 12 ������, 3 ♀♀, 16.1���23.5 mm SL, same collection data as for holotype (MRAC 2016-019- P-94-108); 13 ������, 18.9���26.6 mm SL, upper Alow�� River, 0.70581 S, 9.47592 E, 48 m a.s.l., field reference code CHRSP 6-Alow��, 4 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019-P-109-121). Differential diagnosis Differs from all other species in A. alpha group through combination of following features: head with very intense reddish colour, flanks bluish-orange, ventral region orange (vs never same colour pattern). Distinguished from all other species of Chromaphyosemion by an alpha-shaped mark on pre- and postopercular region (vs no alpha-shaped mark, only some red macules). Colouration of live males (Fig. 6E) FLANKS AND VENTER. Flanks orange and bluish with two often visible dark lateral stripes, four lines of red dots from opercle to caudal peduncle. Ventral region orange, region between end of the anal fin and caudal peduncle is intense orange. Dorsal region brown and bluish, with two rows of paradorsal copper scales from the operculum to caudal peduncle with two lines of carmine red dots. HEAD. Very intense red, premaxilla reddish, mandible reddish with black lower lips, reddish supraorbital region, reddish infraorbital region with black macule, postorbital region bluish-grey with black macule, orange pre-opercle with two black macules, orange opercle with one black macule; black macules on pre- and post-opercular regions, revealing alpha-shaped mark. FINS. Dorsal fin orange, blue on posterobasal portion of fin, with rows of carmine red dots between rays, carmine red streaks on distal and posterobasal portions of fin. Orange acumen on apex. Anal fin orange, with blue zone near submarginal band, regular, red submarginal band, blue marginal band and orange acumen. No punctuation. Caudal fin blue, orange on upper and lower lobes, with some red dots on median region, very long red streaks on median region and in upper and lower lobes, irregular, red submarginal band, blue marginal band and orange acumens. Pelvic fins orange with no punctuation, blue zone near submarginal band, submarginal red band, blue marginal band. Pectoral fins with orange reflections. Colouration of live females (Fig. 6F) FLANKS AND VENTER. Flanks pale beige, four lines of red dots from opercle to caudal peduncle, two dark lateral stripes, venter pale beige, white on basal portion. Two rows of paradorsal brown scales in dorsal region from operculum to caudal peduncle with red dots. HEAD. Premaxilla brown, mandible yellow-orange with black lower lips, with brown supraorbital region, white infraorbital region with black macule, white postorbital region with one black macule, pale blue pre-opercle, orange opercle with two macules. FINS. Dorsal fin yellow-green, orange on distal portion, with rows of carmine red dots between rays. Anal fin translucent, orange zone on distal portion, blue on edge. Caudal fin translucent, orange on ventral portion of fin, red dots on dorsal portion of the fin near caudal peduncle. Pelvic fins translucent with orange reflection, blue reflection on edges. Pectoral fins translucent. Colouration of ethanol-preserved males and females (Fig. 6 G���H) FLANKS AND VENTER. Flanks of males grey with four lines of red dots, venter whitish. Two rows of paradorsal red scales in grey dorsal region, the operculum to caudal peduncle, with two visible greyish lateral stripes. Flanks of females beige with two grey lateral stripes, four lines of red dots from opercle to caudal peduncle, incomplete near the peduncle; venter yellowish, with two grey lateral stripes. Two rows of paradorsal red scales in brown dorsal region, from operculum to caudal peduncle. HEAD. Male with whitish mandible with black lower lips (Alow�� specimens: orange below mandible), infraorbital region with one red macule, orange pre-opercular region and opercle region, and opercle with two small black macules. Head of female with black lower lips, infraorbital region with red macule, orange opercle. FINS. Dorsal fin of male light orange with red dots and some red streaks on edge. Anal fin orange with red submarginal band. Caudal fin orange on median portion, with red streaks on upper portion, and red submarginal band. Dorsal fin of female whitish, rows of red dots between rays. Anal fin whitish, with no red dots. Caudal fin whitish, with some red dots on upper portion, red streaks on edge. Distribution and habitat This species has been found at two localities, one in the Nieng�� River (Table 1, Fig. 1) flowing towards Lake Gom��, itself flowing into the lower Ogoou�� River, and one in the Alow�� River, flowing towards Lake Alombi��, also flowing into the lower Ogoou�� River. The species has never been found elsewhere and seems to be endemic to this part of the lower Ogoou�� hydrographic basin. The habitat of this species differs quite significantly from that of the five other species: all specimens were found in 3 to 5 metre wide rivers with fast running water, and sandy bottoms with no aquatic vegetation. They were hidden in tree roots along the riverbanks, or under dead leaves at the mouth of small secondary brooks, but they were not found in the small brooks themselves. This species was found in syntopy with an undescribed species of Aphyosemion and an undescribed species of Plataplochilus., Published as part of Agn��se, Jean-Fran��ois, Chirio, Laurent, Legros, Olivier, Oslisly, Richard & Bh��, Herv�� Mv��, 2018, Unexpected discovery of six new species of Aphyosemion (Cyprinodontiformes, Aplocheilidae) in the Wonga-Wongu�� Presidential Reserve in Gabon, pp. 1-28 in European Journal of Taxonomy 471 on pages 21-24, DOI: 10.5852/ejt.2018.471, http://zenodo.org/record/3825049

Aphyosemion aurantiacum Chirio, Legros & Agn��se sp. nov. urn:lsid:zoobank.org:act: 93840539-567F-4817-B774-3568D388E094 Fig. 6 A���D, Table 7 Etymology The specific epithet refers to the main colour of this species (dark orange). Material examined Holotype GABON: adult ���, 33 mm SL (39.7 mm TL), W��z�� spring, 0.58186 S, 9.46718 E, 89 m a.s.l., field reference code CHRSP5 -sources W��z��, 3 Jul. 2014, Laurent Chirio leg. (MRAC 2016-019 -P-64). Paratypes GABON: 4 ������, 5 ♀♀, 23.4���29.9 mm SL, same collection data as for holotype (MRAC 2016-019-P- 65-73); 18 ������, 22.2 ���32.1 mm SL, northern tributary of W��z�� River, 0.56336 S, 9.33732 E, 45 m a.s.l., field reference code CHRSP 5-W��z��2, 1 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019-P-74-91); 1 ♀, 23 mm SL, southern tributary of W��z�� River, 0.66401 S, 9.42652 E, 87 m a.s.l., field reference code CHRSP 5-W��z��3, 5 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019-P-92). Differential diagnosis Differs from all other species in A. alpha group through combination of following features: head orange, flanks beige, ventral region orange (vs never the same colour pattern), orange anal fin with no punctuation (vs blue-orange, purplish-blue or orange with punctuation). Distinguished from all other species of Chromaphyosemion by an alpha-shaped drawing in pre- and post-opercular region (vs no alpha-shaped drawing, only some red macules). Colouration of live males (Fig. 6A) FLANKS AND VENTER. Flanks beige with two grey, rarely visible lateral stripes, four lines of red dots from opercle to caudal peduncle. Ventral region orange and region between end of anal fin and caudal peduncle intense orange, two rows of blue iridescent scales between end of anal fin and caudal peduncle. Dorsal region brown, with two rows of paradorsal copper scales from operculum to caudal peduncle with two lines of carmine red dots. HEAD. Orange with premaxilla brown, mandible orange with black lower lips, brown supraorbital region, orange infraorbital region with black macule, postorbital region orange with two black macules, orange pre-opercle with one black macule, orange opercle with two black macules; black macules on pre- and post-opercular region reveal an alpha-shaped drawing. FINS. Dorsal fin blue, large orange zone on rays, rows of carmine red dots between rays, and carmine red streaks on distal and posterobasal portions of fin. Orange acumen on apex. Anal fin orange, blue zone near submarginal band, regular, red submarginal band, blue marginal band, orange acumen. No punctuation. Caudal fin blue with orange caudal peduncle, 5���6 red dots in median region, very long red streaks in median region and in upper and lower lobes, regular, red submarginal band, blue marginal band, and orange acumens. Pelvic fins orange with no punctuation, submarginal red band and blue marginal band. Pectoral fins with orange reflections. Colouration of live females (Fig. 6B) FLANKS AND VENTER. Flanks pale yellow, with four lines of red dots from opercle to caudal peduncle, two greyish lateral stripes, yellow venter, white on basal portion. Two rows of paradorsal golden scales in dorsal region from operculum to start of anal fin with red dots, copper scales from start of anal fin to caudal peduncle with red dots. HEAD. Premaxilla brown, mandible pale yellow with black lower lips, brown supraorbital region, white infraorbital region with black macule, white postorbital region with two red macules, yellow pre-opercle with red dot, yellow opercle with two red dots. FINS. Dorsal fin yellow-green, with rows of carmine red dots between rays, red streaks on distal portion. Anal fin blue on basal portion with row of red dots between rays, some red streaks between rays on median portion, pale orange on distal portion. Caudal fin yellow-green near caudal peduncle, with some red dots on basal portion, red streaks between rays from median to distal portion. Pelvic fins translucent with blue reflection on the edge. Pectoral fins translucent. Colouration of ethanol-preserved males and females (Fig. 6 C���D) FLANKS AND VENTER. Flanks of males grey-yellow with no red dots, venter grey-yellow. Two rows of paradorsal black scales in grey-yellow dorsal region from operculum to caudal peduncle, visible greyish upper lateral stripe. Flanks of females beige with two grey lateral stripes and two lines of two to three red dots behind opercle. Venter beige, with two grey lateral stripes. Two rows of paradorsal red scales in grey dorsal region from operculum to caudal peduncle. HEAD. Head of male grey-yellow mandible with black lower lips, grey-yellow infraorbital region with small black macule, grey-yellow pre-opercular region, opercle with two black macules; dark macules in post-opercular region. Head of female with black lower lips, infraorbital region with black macule, dark opercle. FINS. Dorsal fin of male orange with two to three black dots on basal portion, streaks between rays on distal portion. Anal fin orange with dark rays. Caudal fin orange with many red streaks on distal portion, red submarginal band. Dorsal fin of female light orange, rows of red dots between rays. Anal fin greyish with no red dots. Caudal fin light orange, with some red dots on upper portion, red streaks on edge. Distribution and habitat This species has been found at three localities in the W��z�� Basin (Table 1, Fig. 1) and never elsewhere. The species seems to be endemic to this hydrographic basin. It lives only in very small forest streams and water holes, often with a bottom consisting of roots and dead leaves, where it can be very abundant. In the southern-most locality, it was found hidden under dead leaves along the river banks in a 2 metre wide river with a sandy bottom. This species was found in syntopy with three undescribed species of Aphyosemion, Epiplatys and Plataplochilus., Published as part of Agn��se, Jean-Fran��ois, Chirio, Laurent, Legros, Olivier, Oslisly, Richard & Bh��, Herv�� Mv��, 2018, Unexpected discovery of six new species of Aphyosemion (Cyprinodontiformes, Aplocheilidae) in the Wonga-Wongu�� Presidential Reserve in Gabon, pp. 1-28 in European Journal of Taxonomy 471 on pages 20-21, DOI: 10.5852/ejt.2018.471, http://zenodo.org/record/3825049

Aphyosemion pusillum Chirio, Legros & Agnèse sp. nov. urn:lsid:zoobank.org:act: 529ADFCC-1E00-4715-A157-1281E749DE48 Fig. 5 E–F, Table 6 Etymology The specific epithet refers to the small size of this species. Material examined Holotype GABON: adult ♁, 28.5 mm SL (33.8 mm TL), bridge on Okoyo River, 0.55590 S, 9.21322 E, 10 m a.s.l., field reference code CHRSP4 - Okoyo, 1 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019 -P-57). Paratypes GABON: 2 ♁♁, 24.5–24.8 mm SL, same collection data as for holotype (MRAC 2016-019-P-58-59); 4 ♁♁, 20.6–23 mm SL, bridge on Pembé River, 0.61282 S, 9.15650 E, 5 m a.s.l., field reference code CHRSP 4-Pembé, 1 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019-P-60-63). Differential diagnosis Distinguished from all other species in A. alpha group by two delimited orange zones on body: orange portion on opercle and orange portion above pelvics fins (vs no orange portion) with beige ventral region (vs yellow-orange, white bluish or orange), anal fin orange, blue near basal portion and near submarginal red band, no punctuation (vs never a similar colour pattern). Distinguished from all other species of Chromaphyosemion by alpha-shaped mark on pre- and postopercular region, especially visible on preserved specimens (vs no alpha-shaped mark, only some red macules). Colouration of live males (Fig. 5E) FLANKS AND VENTER. Flanks beige with two dark lateral stripes, two lines of small red dots from opercle to caudal peduncle. Ventral region beige with some blue iridescent scales between end of anal fin and caudal peduncle, orange portion above pelvics fins. Dorsal region light brown, two rows of paradorsal copper scales from operculum to caudal peduncle with two lines of red dots. HEAD. Beige with premaxilla brown, mandible yellow orange with black lower lips, brown supraorbital region, beige infraorbital region with black macule, postorbital region beige with one black macule, beige preopercle with one black macule, opercle yellow orange in background with orange zone with four black macules; black macules on pre- and postopercular region reveal incomplete alpha-shaped mark. FINS. Dorsal fin orange, yellowish on edge of fin, blue on posterobasal portion of fin, rows of carmine red dots between rays, red streaks on edge of fin, orange acumen on apex. Anal fin orange, blue near basal portion of fin and near submarginal band, regular red submarginal band, yellow green marginal band, small orange acumen. No punctuation. Caudal fin blue with beginning of upper and lower lobes light orange, red dots on upper part of fin, long red streaks on upper and median regions, red regular submarginal band, blue marginal band, orange acumens. Pelvic fins orange without punctuation, blue near submarginal band, submarginal red band and yellow green marginal band. Pectoral fins translucent. Colouration of live females Unknown Character N HT Min Max Mean SD D 7 10 9 12 10.43 0.98 A 7 11 11 14 12.29 1.11 D/A 7 0 0 2 1.43 0.98 26.14 L.L. 7 27 (+2) 24 (+2) 27 (+3) 1.21 (+0.49) (+2.29) pDor 7 13 13 15 13.57 0.79 TRAV 7 8 7 8 7.43 0.53 S.L. 7 28.5 20.6 28.5 23.59 2.68 T.L. (%) 7 119 114 122 117.72 2.6 P.D. (%) 7 56 56 61 58.08 2.52 P.A (%) 7 65 57 65 60.48 2.99 P.V.(%) 7 52 43 52 47.3 3.19 Ht (%) 7 21 13 21 16.63 2.44 dcp (%) 7 11 7 13 10.29 1.84 Hd (%) 7 27 27 36 30.27 3.15 I.O. (%) 7 14 12 15 13.91 1.16 Eye (%) 7 6 6 9 7.53 0.99 Colouration of ethanol preserved males (Fig. 5F) FLANKS AND VENTER. Grey with three incomplete lines of red dots, venter beige with orange portion, white lower part, two grey lateral stripes. Two rows of paradorsal red scales in grey dorsal region from operculum to caudal peduncle. HEAD. White mandible with black lower lips, white infraorbital region with black macule, white preopercular region, orange opercle; one dark macule in postopercular region. FINS. Dorsal fin grey with rows of grey dots between rays. Anal fin with grey area on basal portion. Caudal fin grey with some red streaks on upper lobe, red dots in median portion. Colouration of preserved females Unknown. Distribution and habitat This small species has been found at only two localities in the Okoyo and Pembé Basins (Table 1, Fig. 1) and never elsewhere. The species seems to be endemic to these two small, coastal hydrographic basins, situated just north of the Wézé drainage. In the Okoyo Basin, A. pusillum Chirio, Legros & Agnèse sp. nov. was found out of the main course of the river, in small, muddy streams less than 1 m wide. In the Pembé Basin, it was found directly in the course of this small river, hidden among dead leaves and water plants, in quiet places. This species was found in syntopy with an undescribed species of Aphyosemion, two undescribed species of Epiplatys and an undescribed species of Plataplochilus.

Aphyosemion barakoniense Chirio, Legros & Agn��se sp. nov. urn:lsid:zoobank.org:act: 93CAFA79-3B4F-4F39-8430-D9A0DB9A58C5 Fig. 5 A���D, Table 5 Etymology The specific epithet refers to the river in which the species was found. Material examined Holotype GABON: adult ���, 39.9 mm SL (48.9 mm TL), lower Barakoni�� River, 0.47664 S, 9.26483 E, 5 m a.s.l., field reference code CHRSP3 - Basse Barakoni��, 2 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019 -P-19). Paratypes GABON: 7 ������, 10 ♀♀, 21.5���46.6 mm SL, same data as for holotype (MRAC 2016-019-P-20-36); 12 ������, 8 ♀♀, 20.7���37.5 mm SL, upper Barakoni�� River, 0.45815 S, 9.33465 E, 55 m a.s.l., field reference code CHRSP 3-Haute Barakoni��, 3 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019-P-37-56). Differential diagnosis Differs from all other species in A. alpha group through combination of following features: head orange, flanks grey-mauve, ventral region orange (vs never same colour pattern), anal fin orange with some red dots (vs no punctuation or only black dots on posterobasal portion for A. flavocyaneum Chirio, Legros & Agn��se sp. nov. and A. flammulatum Chirio, Legros & Agn��se sp. nov.). Distinguished from all other species of Chromaphyosemion by alpha-shaped mark in pre- and post-opercular region (vs no alphashaped mark, only some red macules). Colouration of live males (Fig. 5A) FLANKS AND VENTER. Flanks grey-mauve with two dark lateral stripes, three lines of very dark red dots from opercle to caudal peduncle. Ventral region orange with some blue iridescent scales between end of anal fin and caudal peduncle. Dorsal region brown, two rows of paradorsal copper scales in dorsal region from operculum to caudal peduncle with two lines of carmine red dots. HEAD. Orange, premaxilla brown, mandible orange with black lower lips, with brown supraorbital region, orange infraorbital region with black macule, postorbital region orange with two black macules, orange pre-opercle with two black macules, orange opercle with three black macules; black macules on pre- and post-opercular regions reveal alpha-shaped drawings. FINS. Dorsal fin blue on basal portion, orange on upper portion, yellowish on edge of fin, with rows of carmine red dots between rays, orange acumen on apex. Anal fin mauve on basal portion, orange on median portion, yellowish portion near the submarginal band, with some carmine red macules, regular, red submarginal band, blue marginal band, small orange acumen.Caudal fin light mauve, with tips of upper and lower lobes orange, red dots on median region, short red streaks in distal region and in upper and lower lobes, irregular red submarginal band, blue marginal band, orange acumens. Pelvic fins orange with no punctuation, submarginal red band, blue marginal band. Pectoral fins with orange reflections. Colouration of live females (Fig. 5B) FLANKS AND VENTER. Flanks beige-pink, four lines of red dots from opercle to caudal peduncle, two greyish lateral stripes, venter yellow, white on basal portion. Two rows of paradorsal copper scales in dorsal region from operculum to caudal peduncle with red dots. HEAD. Premaxilla brown, mandible yellow; orange zone on side portion with black lower lips, brown supraorbital region, white infraorbital region with black macule, orange postorbital region with two black macules, orange pre-opercle, and orange opercle with two black dots. FINS. Dorsal fin intense orange, with rows of carmine red dots between rays. Anal fin orange on the median portion with no dots. Caudal fin intense orange near caudal peduncle, red dots between rays. Pelvic fins with orange reflection, blue reflection on edges. Pectoral fins translucent. Colouration of ethanol-preserved males and females (Fig. 5 C���D) FLANKS AND VENTER. Flanks of males dark grey with three lines of red dots, venter grey-yellow. Two rows of paradorsal red scales in brown dorsal region from operculum to caudal peduncle. Flanks of females beige with two dark lateral stripes, six lines of red dots from opercle to caudal peduncle, venter greyyellow. Two rows of paradorsal red scales in grey dorsal region, from operculum to caudal peduncle. HEAD. Premaxilla and mandible of male grey, with black lower lips, orange infraorbital region with black macule, orange pre-opercular region, orange opercle with one red macule; dark macules in postopercular region. Head of female with black lower lips, infraorbital region with red macule. FINS. Dorsal fin of male orange with rows of red dots between rays. Anal fin orange with some small red dots, red sumarginal band. Caudal fin orange with many red dots on basal portion, red streaks on edge and in upper and lower lobes. Dorsal fin of female orange, with rows of red dots between rays. Anal fin orange, with red streaks between rays. Caudal fin orange, with rows of red dots between rays on median portion, red streaks on edge. Distribution and habitat This species has been found at only two localities in the Barakoni�� Basin (Table 1, Fig. 1) and never elsewhere. It seems to be endemic to this small, coastal hydrographic basin. In the upper Barakoni��, where the river is less than 1 m wide, the fish live among roots or dead leaves in the middle of the river. In the lower Barakoni��, where the river can be 2 to 3 m wide, they are not found in the main course, but only in small water holes of stagnant water close to the river, hidden among dead leaves and mud, and there, they can be very abundant. This species was found in syntopy with an undescribed species of Aphyosemion., Published as part of Agn��se, Jean-Fran��ois, Chirio, Laurent, Legros, Olivier, Oslisly, Richard & Bh��, Herv�� Mv��, 2018, Unexpected discovery of six new species of Aphyosemion (Cyprinodontiformes, Aplocheilidae) in the Wonga-Wongu�� Presidential Reserve in Gabon, pp. 1-28 in European Journal of Taxonomy 471 on pages 15-17, DOI: 10.5852/ejt.2018.471, http://zenodo.org/record/3825049

Aphyosemion pusillum Chirio, Legros & Agn��se sp. nov. urn:lsid:zoobank.org:act: 529ADFCC-1E00-4715-A157-1281E749DE48 Fig. 5 E���F, Table 6 Etymology The specific epithet refers to the small size of this species. Material examined Holotype GABON: adult ���, 28.5 mm SL (33.8 mm TL), bridge on Okoyo River, 0.55590 S, 9.21322 E, 10 m a.s.l., field reference code CHRSP4 - Okoyo, 1 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019 -P-57). Paratypes GABON: 2 ������, 24.5���24.8 mm SL, same collection data as for holotype (MRAC 2016-019-P-58-59); 4 ������, 20.6���23 mm SL, bridge on Pemb�� River, 0.61282 S, 9.15650 E, 5 m a.s.l., field reference code CHRSP 4-Pemb��, 1 Mar. 2016, Laurent Chirio leg. (MRAC 2016-019-P-60-63). Differential diagnosis Distinguished from all other species in A. alpha group by two delimited orange zones on body: orange portion on opercle and orange portion above pelvics fins (vs no orange portion) with beige ventral region (vs yellow-orange, white bluish or orange), anal fin orange, blue near basal portion and near submarginal red band, no punctuation (vs never a similar colour pattern). Distinguished from all other species of Chromaphyosemion by alpha-shaped mark on pre- and postopercular region, especially visible on preserved specimens (vs no alpha-shaped mark, only some red macules). Colouration of live males (Fig. 5E) FLANKS AND VENTER. Flanks beige with two dark lateral stripes, two lines of small red dots from opercle to caudal peduncle. Ventral region beige with some blue iridescent scales between end of anal fin and caudal peduncle, orange portion above pelvics fins. Dorsal region light brown, two rows of paradorsal copper scales from operculum to caudal peduncle with two lines of red dots. HEAD. Beige with premaxilla brown, mandible yellow orange with black lower lips, brown supraorbital region, beige infraorbital region with black macule, postorbital region beige with one black macule, beige preopercle with one black macule, opercle yellow orange in background with orange zone with four black macules; black macules on pre- and postopercular region reveal incomplete alpha-shaped mark. FINS. Dorsal fin orange, yellowish on edge of fin, blue on posterobasal portion of fin, rows of carmine red dots between rays, red streaks on edge of fin, orange acumen on apex. Anal fin orange, blue near basal portion of fin and near submarginal band, regular red submarginal band, yellow green marginal band, small orange acumen. No punctuation. Caudal fin blue with beginning of upper and lower lobes light orange, red dots on upper part of fin, long red streaks on upper and median regions, red regular submarginal band, blue marginal band, orange acumens. Pelvic fins orange without punctuation, blue near submarginal band, submarginal red band and yellow green marginal band. Pectoral fins translucent. Colouration of live females Unknown Character N HT Min Max Mean SD D 7 10 9 12 10.43 0.98 A 7 11 11 14 12.29 1.11 D/A 7 0 0 2 1.43 0.98 26.14 L.L. 7 27 (+2) 24 (+2) 27 (+3) 1.21 (+0.49) (+2.29) pDor 7 13 13 15 13.57 0.79 TRAV 7 8 7 8 7.43 0.53 S.L. 7 28.5 20.6 28.5 23.59 2.68 T.L. (%) 7 119 114 122 117.72 2.6 P.D. (%) 7 56 56 61 58.08 2.52 P.A (%) 7 65 57 65 60.48 2.99 P.V.(%) 7 52 43 52 47.3 3.19 Ht (%) 7 21 13 21 16.63 2.44 dcp (%) 7 11 7 13 10.29 1.84 Hd (%) 7 27 27 36 30.27 3.15 I.O. (%) 7 14 12 15 13.91 1.16 Eye (%) 7 6 6 9 7.53 0.99 Colouration of ethanol preserved males (Fig. 5F) FLANKS AND VENTER. Grey with three incomplete lines of red dots, venter beige with orange portion, white lower part, two grey lateral stripes. Two rows of paradorsal red scales in grey dorsal region from operculum to caudal peduncle. HEAD. White mandible with black lower lips, white infraorbital region with black macule, white preopercular region, orange opercle; one dark macule in postopercular region. FINS. Dorsal fin grey with rows of grey dots between rays. Anal fin with grey area on basal portion. Caudal fin grey with some red streaks on upper lobe, red dots in median portion. Colouration of preserved females Unknown. Distribution and habitat This small species has been found at only two localities in the Okoyo and Pemb�� Basins (Table 1, Fig. 1) and never elsewhere. The species seems to be endemic to these two small, coastal hydrographic basins, situated just north of the W��z�� drainage. In the Okoyo Basin, A. pusillum Chirio, Legros & Agn��se sp. nov. was found out of the main course of the river, in small, muddy streams less than 1 m wide. In the Pemb�� Basin, it was found directly in the course of this small river, hidden among dead leaves and water plants, in quiet places. This species was found in syntopy with an undescribed species of Aphyosemion, two undescribed species of Epiplatys and an undescribed species of Plataplochilus., Published as part of Agn��se, Jean-Fran��ois, Chirio, Laurent, Legros, Olivier, Oslisly, Richard & Bh��, Herv�� Mv��, 2018, Unexpected discovery of six new species of Aphyosemion (Cyprinodontiformes, Aplocheilidae) in the Wonga-Wongu�� Presidential Reserve in Gabon, pp. 1-28 in European Journal of Taxonomy 471 on pages 18-19, DOI: 10.5852/ejt.2018.471, http://zenodo.org/record/3825049

WOS:000438892600002

WOS:000432663000002; International audience

A potential human footprint on Western Central African rainforests before the Common Era has become the focus of an ongoing controversy. Between 3,000 y ago and 2,000 y ago, regional pollen sequences indicate a replacement of mature rainforests by a forest–savannah mosaic including pioneer trees. Although some studies suggested an anthropogenic influence on this forest fragmentation, current interpretations based on pollen data attribute the "rainforest crisis" to climate change toward a drier, more seasonal climate. A rigorous test of this hypothesis, however, requires climate proxies independent of vegetation changes. Here we resolve this controversy through a continuous 10,500-y record of both vegetation and hydrological changes from Lake Barombi in Southwest Cameroon based on changes in carbon and hydrogen isotope compositions of plant waxes. δ13C-inferred vegetation changes confirm a prominent and abrupt appearance of C4 plants in the Lake Barombi catchment, at 2,600 calendar years before AD 1950 (cal y BP), followed by an equally sudden return to rainforest vegetation at 2,020 cal y BP. δD values from the same plant wax compounds, however, show no simultaneous hydrological change. Based on the combination of these data with a comprehensive regional archaeological database we provide evidence that humans triggered the rainforest fragmentation 2,600 y ago. Our findings suggest that technological developments, including agricultural practices and iron metallurgy, possibly related to the large-scale Bantu expansion, significantly impacted the ecosystems before the Common Era.

Le Cameroun développe depuis plus d'une décennie de grands projets d'infrastructures : axe routiers, pipelines, centrales thermiques, chemin de fer, barrages, concessions minières, qui vont nécessiter l'ouverture de grandes superficies de terre et générer de nombreux emplois dont le pays a fort besoin. Ils vont aussi révéler quantité d'objets, d'artefacts, signes de présence humaine qui étaient enfouis dans le sol depuis des millénaires; c'est à ce niveau qu'intervient I 'Archéologie Préventive, discipline récente qui va rechercher et sauver les restes matériels anciens, contribuer à une meilleure perception des peuples anciens et enrichir le Patrimoine culturel national.

International audience; Depuis près de quinze ans, avec l’aide de la coopération internationale, de consortiums et de bailleurs de fonds, l’archéologie de prévention et de sauvetage s’est fortement développée en Afrique. Le Cameroun et le Gabon, par exemple, ont développé de grands projets d’infrastructures : pipelines, routes, centrales thermiques, barrages, carrières… Ces grands chantiers sont réalisés en respectant l’objectif d’intérêt général de sauvegarde du patrimoine national, grâce au développement d’une archéologie de sauvetage dans certains cas (découvertes après ou pendant les travaux) et, depuis peu, d’un véritable volet d’archéologie préventive. C’est grâce au respect des lois de protection du patrimoine culturel lors des grands travaux publics et à l’instauration systématique d’un volet d’archéologie préventive dans l’étude d’impact environnemental et social (EIE) et dans le programme de gestion environnementale et sociale (PGES) correspondant aux mesures de compensation que sont financées les opérations de diagnostic, de sondages et de fouilles archéologiques. La question fondamentale, lors de ces EIE, sera de savoir quelles seront les procédures (diagnostic) et les méthodes (lecture du paysage) qui nous conduiront à découvrir des sites archéologiques et à les classer en fonction de leur priorité. Nous verrons ensuite à travers trois exemples d’archéologie de sauvetage et d’archéologie préventive comment on a appliqué la méthodologie de recherche dans le contexte forestier d’Afrique centrale.

Le Cameroun est l'un des pays leader de l'archéologie de sauvetage en Afrique Centrale depuis une dizaine d'années. Ce leadership est l'oeuvre concertée d'une part entre l'État, les entreprises et d'autre part, les bailleurs de fonds, les archéologues. Les programmes scientifiques d' archéologie étant rares et coûteux, l'archéologie de sauvetage apparaît de plus en plus comme l'une des voies incontournables non seulement pour l'acquisition de nouvelles données sur l'histoire ancienne du Cameroun, mais aussi la formation pratique des archéologues. Les résultats obtenus depuis l'implication de la sauvegarde du patrimoine culturel archéologique dans les travaux d'aménagement sont éloquents. Plusieurs régions n'auraient été prospectées sans l'opportunité qu'offraient certains projets infrastructurels, ce qui est le cas du site de la centrale à gaz de Kribi (Mpolongwé-Kribi).

International audience; La découverte des premières gravures rupestres en 1987, témoins de cultures millénaires, a permis de poser un nouveau regard sur l’histoire du pays. Ces découvertes se cantonnaient respectivement dans la moyenne vallée de l’Ogooué précisément dans la zone d’Otoumbi, le parc national de la Lopé et dans la haute vallée de l’Ogooué sur le site de Kaya Kaya (Oslisly 1993, 1997). Dans les années 90, les prospections archéologiques dans la Lopé ont permis de reconnaitre de nouveaux rochers gravés dont certains constituent le sentier écotouristique de Doda. En 2007, les gravures rupestres de la moyenne vallée ont largement contribué au classement au patrimoine mondial du parc national de la Lopé en tant que site mixte nature culture de l’Unesco. En 2015 lors de l’expédition pluridisciplinaire menée sur les grottes de Lastoursville, de petites gravures sont signalées dans la grotte de Lipopa.

Mal connue et associée à toutes sortes de préjugés, l'Afrique centrale fait l'objet de recherches archéologiques ponctuelles depuis les années 1950, et réellement suivies depuis 1980. Les études paléoenvironnementales démontrent alors, contre toute attente, que le massif forestier d'Afrique centrale, deuxième au monde après celui de l’Amazonie, a énormément varié, par sa superficie et sa composition.