Coronatella (Coronatella) circumfimbriata

Coronatella (Coronatella) circumfimbriata (Megard, 1967) Figs (9A-H). Megard, 1967: 37-40, Fig. 1-7, Pl. I, Fig. 1-6 (Alona); Smirnov, 1971: 359, Fig. 414 (Alona); Sinev, 2009: 65-70, Fig. 4-5 (Alona); Sinev & Silva-Briano, 2012: 20, Fig. 11A-D. Type locality. Lake Itasca, Clearwater County, Minnesota, U.S.A. Type material. Holotype. Female, The Natural History Museum, London, U.K., 1966.3.21.3. Material examined here. Over 100 parthenogenetic females from pond #9, North Dog Leg, Texas State University Campus, San Marcos, Texas, USA, 15.02.1978, coll. S. Sisson, DGF-4492; over 40 parthenogenetic females, 4 males from pond at south side of Federal Road 1, 5 miles West from Wiscasset, Maine, USA, 4.09.1981, coll. D. B. Berner, DGF-6224. Material studied earlier. See list of material in Sinev (2009) and Sinev & Silva-Briano (2012). Morphology of studied females agrees with the earlier descriptions of the species (Megard 1967; Sinev 2009). Rudimentary seta 1 on IDL of limb I and additional seta near scraper 1 of limb II (Fig. 9C) was found in both studied populations. Redescription. Male. Redescription of male morphology by Sinev (2009) was based on a single specimen from slide from D.G. Frey collection, so new description of male, based on more abundant material, is provided. General. Body (Fig. 6L) low oval, maximum height at the middle of the body, height/length ratio about 0.55. Ocellus two times smaller than eye. Postabdomen (Fig. 6M) short, evenly narrowing distally along all length, with broadly rounded dorso-distal angle. Ventro-distal angle well-defined, obtuse. Sperm duct openings located ventrally almost at the end of posta- bdomen. Preanal angle well-defined; postanal angle weakly defined. Distal part of postabdomen 1.5 times longer than preanal; anal portion 1.5 times longer than postanal one. Clusters of short setulae in place of marginal denticles; lateral fascicles of setulae same as in female. Postabdominal claw 1.5 times shorter than preanal portion of postabdomen, with five-six moderately thick spines on the inner side. Basal spine long, about 0.25-0.5 length of claw. Antennule (Fig. 6O) thicker than in female, with 10 terminal and 2 lateral aesthetascs. Longest terminal aestetascs as long as antennules itself; lateral aestetascs about 2/3 length of antennule. Male seta arising at 3/4 length from tip, about 1/4 of antennule length. Thoracic limb I (Fig. 8 G-H) with short U-shaped copulatory hook 2 times shorter than limb itself. Copulatory brush present; copulatory brush seta very short. Ventral face of limb below them with double row of short thick setulae. Inner distal lobe without seta 1; setae 2 and 3 shorter and thinner than in female, armed with moderately thick spinules; male seta curved, shorter than seta 2. Taxonomic notes. Morphology of studied males agrees well with initial description of Megard (1967). Male studied by Sinev (2009) was labelled as Alona circumfimbriata by D.G. Frey, it has similar habitus and limb I morphology, but differ from studied here in morphology of postabdominal claw, with long curved basal spine, more similar to that of C. (C.) poppei (see Sousa et al. 2015 for comparison). It is unclear if Sinev (2009) deal with either abnormal specimen or with male of some other Coronatella (Coronatella) species. Distribution: Canada, USA, North and Central Mexico (Sinev 2009; Sinev & Silva-Briano 2012).

Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.