Dondersiidae, Simroth, 1893

Cobo, M. Carmen & Kocot, Kevin M., 2021, On the diversity of abyssal Dondersiidae (Mollusca: Aplacophora) with the description of a new genus, six new species, and a review of the family, Zootaxa 4933 (1), pp. 63-97 : 89

Dondersiidae sp. B

( Figure 8 , Table 2 )

Examined material. DZMB-HH-4795-07 (DZMB-Senckenberg Biozentrum Grindel und Zoologische Museum). Serial sections (nine slides) and sclerite preparations (one stub, five slides). Guinea Basin. DIVA2 Me 63/2 area 4, station 90 (000º 40.49’N, 005º 29.71’W), 5144 m depth .

Description. Elongate body that is circular in cross-section (2.85 mm long, 0.2 mm wide in the middle and anterior region) with rounded anterior end and narrow posterior end (75 μm) with a slight digitiform projection (characteristic of Dondersia ). It is slightly yellowish in 70% ethanol ( Figure 8 B ). It has leaf-shaped scales and solid acicular sclerites of three types: 1) Leaf-shaped scales ( Figure 8 B-1) are the most abundant variety. With a rounded proximal end and smaller than the other scales (25.9 to 37.7 μm long, 10.2 to 15.5 μm wide in its middle part). 2) Solid straight acicular sclerites ( Figure 8 B-3) with a rounded and wide proximal end. The base is between 2 and 3 μm wider than the middle region, which is in turn between 1 and 0.5 μm wider than the apex (66.5 to 167.6 μm long, 4.3 to 6.2 μm wide in the middle region). These sclerites are concentrated at the ventral posterior end of the animal. 3) Solid, curved acicular sclerites ( Figure 8 B-2; 50 to 51 μm long, 5.7 to 6.5 μm wide).

Figures

FIGURE 8. Habitus and sclerites of the undetermined specimens. A. Dondersiidae sp. A. A1. Leaf-shaped scales with a long and narrow acuminate end. A2. Oval leaf-shaped scales. A3, A4. Laminar scales B. Dondersiidae sp. B. B1. Leaf-shaped scales B2. Asymmetric leaf-shaped scales B3. Acicular sclerites. C. Dondersiidae sp. C. C1, C2. Lanceolate leaf-shape scales C3. Rounded leaf-shaped scales C4, C5. Laminar scales. C6. Oar-shaped scales. D. Dondersiidae sp. D. D1. Leaf-shaped scales. D2. Leaf-shaped scales with a flat proximal end D3. Oval scales. D4. Solid, curved acicular sclerites.