The West Mediterranean Alona azorica Frenzel & Alonso, 1988 (Cladocera: Anomopoda: Chydoridae) is composed of two species Author Sinev, Artem Y. Author Alonso, Miguel Author Miracle, Maria Rosa Author Sahuquillo, Maria text Zootaxa 2012 3276 51 68 journal article 10.5281/zenodo.209635 127eb544-102f-4c83-bb4a-fd2acaf74f42 1175-5326 209635 Alona azorica Frenzel & Alonso, 1988 . ( Figs 6 , 8–10 ) Alona azorica Frenzel & Alonso, 1988 : 449 –465, figs 1–8; Alonso, 1996 : 331 –332, fig. 147. Holotype . Female at the Zoological Museum of Hamburg University, K-32354. Studied populations were collected in: Laguna Grande de Gredos (Gredos Range, Ávila, August 1983 ); Marzagón pond (Marzagón, Huelva, May 1979 ); Rocío pond (El Rocío, Huelva, May 1979 ); Laguna de Antela (R. Margalef leg ., Orense, July, 1954); Laguna Corrubedu (Corrubedu, A Coruña, May, 1980); Las Naciones pond (Saucedilla, Cáceres, April, 1986). FIGURE 6 . Distance between head pores in relation to body size in two populations of Alona azorica (Antela, Marzagón) and two populations of A. anastasia sp. nov . (Monreal, Cucharas). Short description: Parthenogenetic female . Body. In lateral view similar to that of previous species, regular oval ( Fig. 8 A–B, 9A), of moderate height, moderately compressed laterally. Maximum height at middle of body, in adults height/length ratio about 0.65–0.72. Dorsal margin uniformly curved; postero-dorsal and postero-ventral angles broadly rounded; posterior margin uniformly curved; ventral margin almost straight; antero-ventral angle rounded. Ventral margin with about 35–45 setae, the first ten setae long, next ten setae short, other setae of moderate length. Postero-dorsal angle ( Fig. 9 B) as in previous species. Valves oblique or with small tubercules in dorsal portion, fully tuberculated specimens not recorded. Head same as in the previous species. Head shield ( Fig. 8 C) similar to that of previous species, but its posterior margin forms a protruding angle with pointed tip, in large specimens posterior portion of head shield elongates and became more narrow. Three major head ( Fig. 8 D, 9C–D) pores with a narrow connection between two anterior pores; in smaller specimens broken connection sometimes present between middle and posterior pore ( Fig 9 C). Distance between medium and posterior pore greatly increases with the size of specimen, varying from 1.5 to 2.5 distances between anterior and middle pore. Minute lateral head pores located at level before anterior major head pore. Labrum ( Fig. 10 A) same as in previous species. Postabdomen ( Fig. 8 E, 9E–F) same as in previous species. Antennula and antenna same as in the previous species. Thoracic limbs. Limbs I–III ( Fig. 10 B–F) same as in the previous species. Limb IV ( Fig. 10 G–H) similar to in previous species but with the following differences: setae 5–6 of exopodite longer, seta 5 as long as seta 4, flame-torch setae of endite IV shorter, more robust and less differentiated in size. Limb V ( Fig. 10 I) as in previous species. Male. For full description see Frenzel & Alonso, 1988 , and Alonso, 1996 . Body similar to that of the previous species. Postabdomen ( Fig. 8 F) similar to that of previous species, but with much less prominent postanal angle, weakly narrowing in postanal portion and postanal angle not developed. Antennule and limb I same as in previous species. Size. According to Frenzel & Alonso (1988) , minimum length of juvenile female 0.19 mm , maximum length of adult female 0.48 mm , length of adult male 0.28–0.34 mm .