Flavalona hudeci (Sinev, 1999) Sinev & Dumont, 2016

Sinev, Artem Y. & Dumont, Henri J., 2016, Revision of the costata-group of Alona s. lato (Cladocera: Anomopoda: Chydoridae) confirms its generic status, European Journal of Taxonomy 223, pp. 1-38 : 28-29

Flavalona hudeci (Sinev, 1999) comb. nov.

Fig. 6 G–J

Alona hudeci Sinev, 1999: 147 .

Alona rusticoides – Hudeč, 1998: 205–207, figs 1–8, 23–31.

Diagnosis (from Hudeč 1998)

Female

Length of adult up to 0.7 mm. Body regular oval ( Fig. 6G ), maximum height at mid-body, height/ length ratio about 0.62.Valves from previous molts not retained. Posteroventral angle without setules protruding beyond valve margins ( Fig. 6I ). Valves oblique or with weak polygonal reticulation.

Eye and ocellus of similar size. Rostrum short, broadly rounded. Posterior margin of head shield broadly rounded. Three major head pores ( Fig. 6H ) of same size, middle pore located slightly closer to posterior pore. Connection between pores narrow. PP about 0.8 IP. Lateral head pores of about 0.25 IP length, lateral pore pockets shallow, with depth about ⅓ of pore length. Labral keel without denticles on anterior margin.

Postabdomen truncated, length about 2.3 heights. Distal margin convex, distal angle prominent, broadly rounded. Dorsal margin weakly convex in preanal part, concave in anal part, straight in postanal part. Distal part of dorsal margin 3 times longer than preanal one. Preanal angle well-defined, postanal angle not defined. Margin of postabdomen provided with 9–11 marginal denticles and 3–4 clusters of marginal setules.About 10 lateral fascicles of setules, middle setules in fascicle being longest. Postabdominal claw 1.3 times longer than preanal portion of postabdomen. Basal spine about 0.15 of length of claw.

Antennule with longest aesthetasc of about ⅔ length of antennule. Scrapers of limb II of similar morphology. Exopodite III ( Fig. 6J ) with seta 6 of about ⅔ length of seta 3. Exopodite IV with seta 1 being longest, setae 2–2 slightly shorter, setae 4–5 about half length of seta 1, setae 6 longer than setae 4–5, about 4/5 length of seta 1. Epipodites IV–V with processes about 1.5 of epipodite length. Exopodite V bilobed.

Male

Unknown.

Differential diagnosis

Flavalona hudeci comb. nov. differs from F. bicolor comb. nov. by a short rostrum, ocellus smaller than eye, and labral keel without denticles; from all other species of the rustica -branch - by its large size, absence of setules on posteroventral corner of valves, and by seta 6 of exopodite III only ca ⅔ as long as seta 3.

Type material

Holotype

Parthenogenetic ♀, British Museum (Natural History), No. 1998.784.

Paratypes

Parthenogenetic 40 ♀♀ from the type locality at the British Museum (Natural History), nos 1998.785– 795, 1998.796–797, 1998.798–810, 1998.811–825.

Type locality

WEST VENEZUELA-BRAZIL: small rock pool on Roraima Tepui (= table mountain).

Distribution

Recorded from a humic-water rock-pool on Roraima tepui in Venezuela ( Hudeč 1998).

Figures

Fig. 6. Flavalona bicolor (Frey, 1965) comb. nov. A–E. Parthenogenetic ♀. A. Lateral view (specimen retaining valves from previous moult). B. Head shield. C. Head pores. D. Labrum. E. Postabdomen. F. Postabdomen of adult ♁. — G–J. Flavalona hudeci (Sinev, 1999) comb. nov., parthenogenetic ♀ G. Lateral view. H. Head pores. I. Posteroventral corner of valves. J. Thoracic limb V. — K–O. Flavalona iheringula (Sinev & Kotov, 2004) comb. nov. K–M. Parthenogenetic ♀. K. Lateral view. L. Head pores. M. Thoracic limb V. N–O. Adult ♁. N. Lateral view. O. Postabdomen. — P. Flavalona sphagnophila (Van Damme & Eggermont, 2011) comb. nov., parthenogenetic ♀, head pores. Figures A–F from Sinev (2009), G–J redrawn from Hudeč (1998), K–M from Sinev (2001), N–O from Kotov & Sinev (2004) and P redrawn from Van Damme & Eggermont (2011).