摘要
</span><i><span style="font-family:Verdana;">Achatina</span></i> <i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:""><span style="font-family:Verdana;"> is a giant land snail taxa endemic to the northern sectors of the Monts Togo, which has been regarded as full species or subspecies of the highly variable, widespread </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> (L.). To address this issue, samples of snails were taken throughout the distribution range of the two taxa in the Dahomey Gap (West Africa) and separated into 112 </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> and 141 </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> according to color of </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">columella and parietal wall. Radulae were compared and shell characters of these 2 species were evaluated through </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">traditional morphometric method. The results indicate that the species cannot be distinguished by overall shell size and radular morphology, but they exhibit significant differences in shell shape and meristic traits. The typical </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span></span><span style="font-family:""> </span><span style="font-family:Verdana;">with vinaceous-red columella</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">has a low-spired shell and an expanded aperture (globose shape) whereas </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> has a higher-spired and smaller aperture (a fusiform shape). We suggest that local environmental effects are probably the causes of morphological divergence between the two taxa. It is likely that peripheral populations of the typical form of </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> would have isolated and developed in the drier facies of the humid forest that individualized in the northern sector of the mountains after the arid or interpluvial period of Holocene. In addition, we find that </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> meets the criteria B2ab</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">(ii, iii) to categorize as “Endangered”. However, whether this latter should be considered as separate species cannot be decided at the current state of knowledge.
</span><i><span style="font-family:Verdana;">Achatina</span></i> <i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:""><span style="font-family:Verdana;"> is a giant land snail taxa endemic to the northern sectors of the Monts Togo, which has been regarded as full species or subspecies of the highly variable, widespread </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> (L.). To address this issue, samples of snails were taken throughout the distribution range of the two taxa in the Dahomey Gap (West Africa) and separated into 112 </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> and 141 </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> according to color of </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">columella and parietal wall. Radulae were compared and shell characters of these 2 species were evaluated through </span><span style="font-family:Verdana;">the </span><span style="font-family:""><span style="font-family:Verdana;">traditional morphometric method. The results indicate that the species cannot be distinguished by overall shell size and radular morphology, but they exhibit significant differences in shell shape and meristic traits. The typical </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span></span><span style="font-family:""> </span><span style="font-family:Verdana;">with vinaceous-red columella</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">has a low-spired shell and an expanded aperture (globose shape) whereas </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> has a higher-spired and smaller aperture (a fusiform shape). We suggest that local environmental effects are probably the causes of morphological divergence between the two taxa. It is likely that peripheral populations of the typical form of </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">achatina</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> would have isolated and developed in the drier facies of the humid forest that individualized in the northern sector of the mountains after the arid or interpluvial period of Holocene. In addition, we find that </span><span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">A</span></i><span style="font-family:Verdana;">. </span><i><span style="font-family:Verdana;">togoensis</span></i><span style="font-family:Verdana;"></i></span></span><span style="font-family:Verdana;"> meets the criteria B2ab</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">(ii, iii) to categorize as “Endangered”. However, whether this latter should be considered as separate species cannot be decided at the current state of knowledge.
作者
Komlan Mawuli Afiademanyo
Kwami Lumo Awaga
Kamilou Ouro-Sama
Hodabalo Dheoulaba Solitoke
Komlan Mawuli Afiademanyo;Kwami Lumo Awaga;Kamilou Ouro-Sama;Hodabalo Dheoulaba Solitoke(Laboratoire d’Ecologie Animale et d’Ecotoxicologie, Département de Zoologie et de Biologie Animale, Faculté des Sciences, Université de Lomé, Togo;Département de Biochimie, Faculté des Sciences, Université de Lomé, Togo;Laboratoire de Gestion, Traitement et Valorisation des Déchets (GTVD), Faculté des Sciences, Université de Lomé, Togo)