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 : 304-305

Bairdoppilata sp. 2

( Figs. 12–13 )

Material. Twelve specimens, including six females and six juveniles representing two instars.

Dimensions. Adult female specimen 3966F, length 869 µm, height 547 µm. See also Table 1 and Figures 2 and 4 .

Descriptive comments. Carapace semicircular in lateral outline, nearly symmetrical (anterior to posterior), with continuously curved, high-arched dorsal margin, lacking angles or sinuosities; greatest height 0.64 of length, located at 0.48 of length; anterodorsal corner not distinguishable, located approximately at 0.30 of length and 0.93 of height; posterodorsal corner not distinguishable, located at approximately 0.67 of length and 0.93 of height; anterodorsal brim located at 0.54 of height; posterodorsal brim located at 0.45 of height; greatest height of ventral indentation located at 0.41 of length and 0.09 of height. Slope (measured from horizontal) of mid-dorsal margin 0o, of anterodorsal margin 39o, of posterodorsal margin 45o, of dorso-caudal margin 44o, of hinge 3o. Very weakly caudate, with barely distinguishable posterodorsal change in slope; length of caudal process 0.06 of length. Surface nearly smooth, with fine microgranular texture, no visible punctae; brown pigmentation over much of central lateral surface. Striate hinge, well developed plumose setae.

Comparisons. B. sp. 2 is approximately the same size as B. alcyonicola , B cratericola , and B. geelongensis and is at the lower end of the published range for B. angolensis ( Fig. 4 ). The high-arched, non-caudate to very weakly caudate lateral outline is shared with B. angolensis and B. balihaiensis (group 2), but both of those species have more distinctly peaked mid-dorsal angles and somewhat subtriangular outlines. All members of group 3 ( B. alcyonicola , B. cratericola , B. cushmani ) have a more sinuous dorsal margin with more prominent caudal process. The surface of B. sp. 2 appears to be smooth, lacking the distinctly punctate texture of these and most species of Bairdoppilata .

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 12. Bairdoppilata sp. 2, all female specimen 3969 F. A, interior of LV, striate hinge; B, right exterior of whole animal before dissection; C, LV exterior with brown pigmentation; D, MSP and NPC in central region of fig. C; E, LV exterior, anterior margin; F, LV exterior, posterior margin, focused low on adhering shreds of RV hinge and setae; G, left posterior region of soft body, showing ovaries, zygum, genital lobes and furcae; H – I, genital lobe, after and before dissection; J, masticatory organ; K, right exterior of whole animal, to show plumose setae in posterior caudal region; L, right exterior, anterodorsal region of fig. B, showing food ball, median eye and accessory dentition. Scale bar = 50 µm.

FIGURE 13. Bairdoppilata sp. 2. A – E, female specimen 3966 F; F, juvenile specimen 3970 J; G – H, female specimen 3972 F; I, juvenile specimen 3965 J (molting); J, juvenile specimen 3964 J. A, right exterior of whole animal; B – C, right exterior, of whole animal, posterior region and anterior region of whole animal; D, anterodorsal region of fig. C, enlarged to show median eye and isthmus; E, median eye, focused on right eye-cup, enlarged from fig. D; F, right exterior of whole animal; G, distal claws of adult antenna; H, right genital lobe before dissection; I, distal claws of juvenile antenna, molting, with adult claws being withdrawn from interior; J, distal claws of juvenile antenna, with anlage of accessory claw. Scale bar = 50 µm.