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Una nueva especie de Iberellus Hesse, 1908 (Pulmonata: Helicidae) en la isla de Eivissa



Se describe una nueva especie, Iberellus tanitianus n.sp., de Eivissa (Archipiélago Balear) de características  conquiológicas semejantes al Iberellus companyonii (Aleron,  1837). Conquiológicamente difiere de esta  especie por tener la última vuelta más ancha; la callosidad en el borde columelar muy visible; la boca algo más amplia hacia el exterior y con el superior más caído; la escultura más fina y regular; las bandas espirales  de menor amplitud e interrupción. Protoconcha con pliegues visibles a 30X. En  cuanto a la genitalia, se diferencia del Iberellus companyonii por la configuración del epifalo, su longitud y la proporción entre éste y el flagelo, así como la inserción del músculo retractor. Iberellus tanitianus n. sp, se distingue de Helix (Archelix?) pythiusensis [sic) Bofill y Aguilar Amat 1924, denominado Iberellus companyonii pythiusensis  (Bofill  y  Aguilar  Amat) por Gasull (1964), protoconcha en la que  se  observan  claramente  a  30X  pliegues junto a la sutura que, iniciándose en el ápice descienden hacia la concha; por sus anfractos menos  globosos, menos translúcidos, de estructura más gruesa; por sus bandas más marcadas; boca oblícua  más  acampanada, peristoma más grueso y reflejado. 


Forés,  M. y Vilella,  M.,  1993.  Boll.  Soc.  Hist.  Nat.  Balears,  36
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