Bairdoppilata

Maddocks, Rosalie F., 2015, New and poorly known species of Bairdoppilata and Paranesidea (Bairdiidae, Ostracoda) from French Frigate Shoals and O’ahu, the Hawaiian Islands, Zootaxa 4059 (2), pp. 277-317 : 305-306

Bairdoppilata sp. 4

( Figs. 17 G–P)

Material. One adult female specimen 3963F.

Dimensions. Adult female 3963F, carapace measured before dissection: Length 1084 µm, height 732 µm. See also Table 1 and Figs. 2 and 4 .

Descriptive comments. Carapace rounded-subtriangular in lateral outline, with very high-arched dorsal margin and nearly straight, steeply sloping anterodorsal margins, lacking angles; greatest height 0.67 of length, located at 0.64 of length; anterodorsal corner not distinguishable, located approximately at 0.33 of length and 0.89 of height; posterodorsal corner not distinguishable, located approximately at 0.67 of length and 0.84 of height; anterodorsal brim located at 0.69 of height; posterodorsal brim located at 0.43 of height; greatest height of ventral indentation located at 0.38 of length and 0.7 of height. Slope (measured from horizontal) of mid-dorsal margin 1o, of anterodorsal margin 38o, of posterodorsal margin 44o, of dorso-caudal margin 35o, of hinge 1o. Caudate, with weak concavity separating dorsal-caudal margin from posterodorsal margin; length of caudal process 0.06 of length. Plumose setae with barely visible barbs. Hinge striate, ends only slightly expanded and scalloped. Surface apparently smooth, with distinct reticular pattern of micropapillae. Seta 2 of furca with a proximal cluster of about 8 lateral barbs (on each side), followed by much tinier barbs or nearly smooth distally.

Comparisons. B. sp. 4 is significantly larger than most shallow-water species ( Fig. 4 ). The broadly arched dorsal margin and gently extended caudal process place B. sp. 4 in shape group 3, together with B. alcyonicola , B. cratericola and B. cushmani . From all of these it differs by the smooth surface with micropapillate microornament, which may reflect cell arrangement in the underlying epidermis.

Figures

FIGURE 2. Carapace dimensions for the species of Bairdoppilata and Paranesidea described here. The assemblages of B. scaura, B. sp. 2 and B. sp. 3 each include two late instars as well as adults; the others include only adult specimens. See also Table 1.

FIGURE 4. Carapace dimensions for 15 shallow-water species of Bairdoppilata. These data include adults only, of species for which the soft parts have been described. See also Table 2.

FIGURE 17. A – F, Bairdoppilata sp. 3, female specimen 3923 F; G – P, Bairdoppilata sp. 4, female specimen 3963 F. A, right exterior of whole animal before dissection, posterior region; B, enlarged proximal barbs of seta 2 of furca; C – D, genital lobes; E, left side of posterior body with zygum, furca and genital lobes; F, dorsal view of genital lobes, zygum, furcae, and postabdominal bristle; G, distal claws of antenna; H – I, tapering proximal barbs of seta 2 of furca; J, masticatory organ; K, right exterior of whole animal, filled with secondary crystals; L, valve fragment with setae and micropapillae; M – N, left exterior of whole animal, caudal region, showing plumose setae at high and low focus; O, left genital lobe and edge-bar of zygum; P, dorsal view of hinge region of decalcified carapace with sinusoidally folded chitin ribbons. Scale bar = 50 µm.