Neonesidea omnivaga Maddocks 1986

Neonesidea omnivaga Maddocks, 1986

(Figure 10 K–N, Graph 4)

1986 Neonesidea omnivaga sp nov: Maddocks in Maddocks & Illife: 45, Figs. 6 A–K.

2000 Neonesidea longisetosa (Brady) —Keyser & Scĥning, p. 582, Pl. 2, fig. 19.

Material: About 30 adult and juvenile, subfossil carapaces and valves.

Dimensions: Female 609F: LVL 0.832 mm, LVH 0.460 mm, RVL 0.827 mm, RVH 0.447 mm. Maddocks (1986) reported erroneous dimensions for the illustrated paratype USNM 216438: LVL 0.54 mm, LVH 0.31 mm, RVL 0.54 mm, RVH 0.29 mm; these dimensions would be juvenile, but her illustrations (Figs. 6 I–K) show adult characters. Keyser & Sch ̂ning (2000) reported the following dimensions: L 0.960 mm, height 0.500. See also Graph 4.

Supplemental Description: The plate is broad with recurved lateral edges. The posterior margin carries a broad medial tooth on either side of the medial gap, followed by about three narrower teeth, which have conical to pyramidal terminations. The corner teeth are multilobed.

Remarks: N. omnivaga resembles N. gerda in shape and polished surface, having a nearly straight ventral margin and an acute posterior angle located at 17% of height. As compared with N. gerda, N. omnivaga is not as high in proportion to length, it may have more angulate lateral outlines, and the central opaque spot is relatively wider. The LV posteroventral margins are nearly smooth, even in well–conserved specimens, with only faint nubs where marginal denticles would be expected. The dorsal outline is more continuously curved than in N. gerda but but shows similar proportions. The RV illustrated by Keyser & Scĥning (2000, Pl. 2, fig. 19) agrees in outline and dimensions with adult N. omnivaga. The male anatomy is unknown.

Distribution: The species is endemic to the Bermuda platform. Living specimens were reported from Harrington Sound, Cherry Pit Cave, Green Bay Cave and Palm Cave by Maddocks & Iliffe (1986). Subfossil specimens occur in sediments of Harrington Sound, Castle Harbour, North Lagoon, and on the South Shore, in water depths of 1–350 fathoms.

GRAPH 7. H/L scatter plot for LV and RV of N. omnivaga. Anatomical males have not been described, but the elongate form of the adult cluster suggests dimorphism of size rather than shape, with females being both higher and longer than males.