Neonesidea decipiens

Neonesidea decipiens (Müller 1894)

(Figure 4 A–G)

1894 Bairdia decipiens M̹ller: 269, Pl. 13, fig. 29, Pl. 14, figs. 10, 21–22.

Material: One dry female carapace (170F) with fragments of soft parts.

Dimensions: Female specimen 170F, LVL 1.304, LVH 0.826 mm, RVL 1.245 mm, RVH 0.746 mm. M̹ller reported the range of lengths as 1.18 to 1.25 mm.

Supplemental Description: The plate is broad and wedge-shaped with gently bowed lateral edges and flared anterior base. The posterior margin carries six broad, multicuspate teeth with mound-shaped to asymmetrically conical terminations, arranged three on each side of a narrow medial gap. The middle tooth is narrower than the first and third. The lateral gap is only slightly wider than the medial gap. The corner teeth are large and multi-lobed. A thick brown stripe or layer runs through the posterior edge of the plate, crossing each of the teeth at its base.

Remarks: The identification of this single female specimen is based on M̹ller’s description of the carapace pigmentation and patch pattern. Several species of Neonesidea in the Bay of Naples have similar H/L proportions and marginal denticulation, and their variability has not been analyzed. Bonaduce et al. (1976) lumped the occurrences of up to five of M̹ller’s species under one name, because of the difficulty of distinguishing them on carapace characters alone. M̹ller (1894, Pl. 14, figs. 33, 34) illustrated a similarly scalloped esophageal plate for an unidentified species of “ Bairdia.”

Distribution: Bay of Naples.