Berguecythere insularis, Coimbra & Bottezini & Machado, 2013

Coimbra, João C., Bottezini, Silvia R. & Machado, Cláudia P., 2013, Ostracoda (Crustacea) from the Archipelago of São Pedro and São Paulo, Equatorial Atlantic, with emphasis on a new Hemicytheridae genus, Iheringia, Série Zoologia 103 (3), pp. 289-301 : 292

Berguecythere insularis sp. nov.

( Figs 28-41 )

Aurila sp. 1 ANTONIETTO et al., 2012:42-43, Fig. 7: 10-19; Table 12.

Type material. Holotype, MP-O-2433, LV, ♀, length: 0.44 mm; height: 0.25 mm. Paratypes. MP-O-2434, RV, ♀, length: 0.42 mm; height: 0.23 mm ; MP-O-2435, RV, ♀, length: 0.42 mm; height: 0.23 mm ; MP-O-2436, LV, ♀, length: 0.46 mm; height: 0.25 mm ; MP-O-2437, LV, ♂, length: 0.44 mm; height: 0.23 mm ; MP-O-2438, RV, ♂, length: 0.43 mm; height: 0.22 mm ; MP-O-2439, carapace, ♀, width: 0.20 mm; length: 0.44 mm ; MP-O-2440, carapace, ♂, width: 0.18 mm; length: 0.45 mm ; MP-O-2441, LV, juvenile, length: 0.37 mm; height: 0.21 mm ; MP-O-2442, LV, juvenile, length: 0.31 mm; height: 0.18 mm ; MP-O-2443, RV, juvenile, length: 0.25 mm; height: 0.14 mm ; MP-O-2444, RV, ♀, length: 0.42 mm; height: 0.23 mm .

Etymology. From Latin origin, insularis = of an island, because of its first record being restricted to an archipelago.

Type locality. Archipelago of São Pedro and São Paulo, Equatorial Atlantic.

Occurrence. See Table III.

Description. A thick-shelled genus of the subfamily Hemicytherinae , subquadrate to subrectangular in lateral view. Greatest height at the anterior cardinal angle. Anterior margin obliquely rounded. Posterior margin caudate in RV and subcaudate in LV. Dorsal margin somewhat conveX in LV and subrectilinear in RV. Ventral margin with conspicuous oral concavity. Surface covered with reticulate ornament with the peripheral fossae secondarily gently punctate. A delicate ridge, which starts at the ventral end, runs parallel to the anterior margin, crosses the well-developed eye tubercle, and becomes more slender along the dorsal margin. An ear-shaped ridge starts around the central area and ascends to its heaviest width in front at the posterior cardinal angle. From there it descends as a short stretch and turns forward and then disappears near the midlength. This ear-shaped ridge gives rise to a posterodorsal protrusion more developed in RV. Normal porecanals sieve-type. In dorsal view acuminate anteriorly, maXimum width posteriorly. In internal view, hinge robustly developed, hemiamphidont, the posterior terminal element of the RV being a dentate bar with 6-7 small teeth and a smooth distal area. Calcified inner lamella well-developed with narrow vestibulae at each end. Radial pore-canals numerous, straight, mostly simple with some intercalated branching ones. Selvage conspicuous and parallel to the outline. Adductor muscle scars a row of four scars, the dorso-median one subdivided. Three frontal scars. SeXual dimorphism conspicuous; male more elongate and less wide, and with a more secondarily reticulate dorsal region.

Figures

Figs 21-36. Triebelina sertata Triebel, 1948: 21, MP-O-2426, LV; 22, MP-O-2427, RV; 23, MP-O-2428, LV, internal, view; 24, MP-O-2429, c, dorsal view. Triebelina sp.: 25, MP-O-2430, LV; 26, MP-O-2431, LV; 27, MP-O-2432, RV, internal view. Berguecythere insularis gen. nov., sp. nov.: 28, MP-O-2433, LV, ♀; 29, MP-O-2434, RV, ♀; 30, MP-O-2435, RV, ♀, internal view; 31, MP-O-2436, LV, ♀, internal view; 32, MP-O- 2437, LV, ♂; 33, MP-O-2438, RV, ♂; 34, MP-O-2436, LV, ♀, central muscle scars, not in scale; 35, MP-O-2439, c, ♀, dorsal view; 36, MP-O- 2440, c, ♂, dorsal view. The scale of all specimens = 100 µm, if no other indication.

Figs 37-50. Berguecythere insularis gen. nov, sp. nov.: 37, MP-O-2441, LV, juvenile; 38, MP-O-2442, LV, juvenile; 39, MP-O-2443, RV, juvenile; 40, MP-O-2444, RV, ♀, anterior marginal pore-canals, not in scale; 41, MP-O-2444, RV, ♀, posterior marginal pore-canals, not in scale. Loxocorniculum tricornatum Krutak, 1971: 42, MP-O-2445, LV, ♂, scale bar = 100 µm; 43, MP-O-2446, RV, ♂, scale bar = 100 µm; 44, MP-O-2447, RV, ♀, scale bar = 100 µm; 45, MP-O-2448, LV, ♀, scale bar = 100 µm. Microcythere sp.: 46, MP-O-2449, RV, scale bar = 20 µm; 47, MP-O-2450, LV; 48, MP-O-2451, LV, internal view; 49, MP-O-2452, RV, duplicature, transmitted light, not in scale; 50, MP-O-2453, c, dorsal view. The scale of all specimens = 50 µm, if no other indication.