Lindia aequorea, De Smet, Willem H., 2015

De Smet, Willem H., 2015, Rotifera from the Mediterranean Sea, with description of ten new species, Zootaxa 4028 (2), pp. 151-196 : 172-173

Lindia aequorea sp. nov.

( Figs 16 , 17 )

Diagnosis. Foot a single pseudosegment. Manubria with stout hook-shaped cauda; unci composed of single blunt major tooth and acute minor tooth, a strong preuncinal tooth, and chisel-shaped subuncus; epipharynx butterflyshaped. Oviparous.

Type locality. Pomonte, Elba Island, ‘il relitto di Pomonte’ (wreck of Elviscott), Tyrrhenian Sea, Italy. In psammon collected on 26.09. 2006, 100 m from shoreline and depth of 10 m; water temperature 23 °C.

Holotype. A female in a permanent, glycerine glass slide mount deposited in the Royal Belgian Institute of Natural Sciences ( RBINS), Brussels, Belgium, No. IG 33082, RIR 223.

Paratypes. One female from type locality in RBINS, No. IG 33082, RIR 253; 1 mounted paratype and 3 SEM trophi preparations in Department of Biology, University of Antwerp.

Additional material. Thirty specimens from type locality, and 3 from sublittoral of La Fonza Esterna, Elba Island, Tyrrhenian Sea.

Etymology. The species name aequorea is a Latin adjective, meaning ‘belonging to the sea, marine’.

Description of female. Body ( Fig. 16 A) elongate fusiform, transversal folds inconspicuous. Head indistinctly offset; auricles not seen. Tail ( Figs 16 B, C) hemispherical, bulging. Foot a single pseudosegment, short. Toes short, fairly robust, with short tubulus, conical in dorsal view, in lateral view dorsal margin slightly arched and ventral margin straight. Single eyespot, small. Retrocerebral sac hemispherical with few minute pigment granules. Vitellarium with 8 nuclei. Oviparous.

Trophi ( Figs 16 D −H, 17) with lyrate rami, with slender, long, caudally projecting sharp alulae; rami tips bifid, weakly revolved around axis. Strong broad ligaments connect both rami, and rami and manubria distally. Fulcrum plate-shaped, tapering distally. Ventral branch of manubria rod-shaped, short, c. 1/4 length shaft of manubrium; shaft of manubria stout, with broad hook-shaped caudum; ‘dorsal branch’ (expanded part of dorsal manubrium chamber) short, more or less semi-lunar; opening of dorsal chamber large, at inner side of manubrium; opening of medial and ventral chamber at outer side of manubrium, small and rounded in ventral chamber, somewhat larger and triangular in medial chamber. Unci with single, stout blunt tooth with stout preuncus ( Fig. 17 G), and lateral expansion with acute toothlet. Subuncus ( Fig. 17 H) a single, stout chisel-shaped element. Epipharynx ( Figs 16 E, 17D) thin, butterfly-shaped.

Measurements. Body (N=3): total length slightly contracted up to 280 µm, toe 21‒22 µm; trophi (N=3): length ~40 µm, ramus inclusive alula 18.9‒19.1 µm, fulcrum 15.7 µm, uncus 8.9‒9.3 µm, manubrium 31.7‒34.0 µm, subuncus 4.2‒4.9, 5.2‒5.4 µm, epipharynx 37.5 × 14.4 µm.

Comments. Lindia aequorea sp. nov. is unambiguously differentiated from its congeners (see Segers 2002) by the characteristic shape of the trophi, in particular the strong, terminally hook-shaped manubria and the butterflyshaped epipharynx. The only other Lindia with caudally hook-shaped manubria is L. euchromatica Edmondson, 1938 , which shows no other affinities with the new species, and inhabits freshwater colonial cyanobacteria and periphyton.

Distribution and ecology. To date only known from sublittoral psammon sampled at Elba Island, Tyrrhenian Sea, 50 and 100 m from shoreline, depth 10 and 30 m, September, water temperature 23 °C.

Figures

FIGURE 16. Lindia aequorea sp. nov. A. Female, slightly twisted, head lateral, trunk ventral; B. tail, dorsal; C. tail, distal pseudosegment and toe, lateral; D. trophi, complete set, ventral; E. epipharynx; F. left manubrium, outer view; G. uncus with preuncinal tooth; H. subuncus. Scale bars: A − C: 50 µm; D − H: 10 µm.

FIGURE 17. Lindia aequorea sp. nov., SEM photographs of trophi. A. Complete set, ventral; B. same as A, frontal; C. complete set, lateral; D. epipharynx; E. left uncus, without preuncinal tooth and subuncus; F. right uncus, with preuncinal tooth and subuncus; G. left preuncinal tooth; H. right subuncus. Scale bars: 10 µm.