Chaetonotus aff. hoanicus Schwank, 1990

Chaetonotus aff. hoanicus Schwank, 1990 View in CoL

Figs 2E View Figure 2 , 4A–C View Figure 4

Locality: PT06, 09 (Fig. 1).

Examined Material: 19 specimens TL 103–194 Μm; FL 5–16 Μm; AL 12–32 Μm; PhL 34–66 Μm; MD 7–15 Μm; DR 20–26; TSl 2–6 Μm; TSw 2–5 Μm; TSp 2–16 Μm; DC 10–13 Μm; DSL 9–24 Μm; VC 4–5; VTSl 11–18 Μm; VTSw 5–10 Μm; VR 25–29; VSL 5–18 Μm .

Remarks: Slender, fusiform habitus. Head clearly five-lobed, with strong arrow-head shaped cephalion with thin wrinkled posterior edge, large dorsolateral elliptical epipleura and lateral hypopleura, small transversal rod-shaped hypostomium posteriorly adjacent to the mouth. Mouth terminal, cylindrical pharynx with small pharyngo-intestinal junction. Cephalic ciliature consists of dorsolateral pairs of ciliary tufts inserted between cephalion and epipleura and ventrolateral one between epipleura and hypopleura, with one longer cilium. Head followed by subtle neck constriction and trunk widens posteriorly. Posterior end bears a short V-shaped furcal base with strong adhesive tubes narrower distally. Anterior sensory bristles on the neck are inserted on specialized smooth scales and posterior on the furca base inserted on specialized double-keeled scales. The dorsal surface is covered by 14 columns of pentalobed scales posteriorly concave with a long single-barbed spine. On the head scales are smaller and anteriorly circular progressively enlarging toward the neck and trunk and elliptical in shape. Ventral interciliary area covered by 5 columns of elliptical keeled scales. Furca base is completely covered with small triangular scales with diverse morphology, some smooth, some spined with a long base resembling a keel with a spiny process. The specimens share the general morphology with Chaenotus hoanicus , in dorsal head and trunk scale shapes, with smaller rounded scales on the head and larger pentalobed on trunk, each bearing a long single barbed spine. Both species feature a dorsal posteriormost set of smaller scales with short simple spines on the furcal base. However, they differ in the number of dorsal columns, with C. hoanicus featuring a larger number of cephalic dorsal scales. On the dorsal furcal base, the present species feature two pairs of larger, stronger single-barbed spines, one larger one laterally to adhesive tube insertion, and smaller medial one with straight spines.

Distribution: Brazil: Casa Nova (BA), and Delmiro Gouveia (AL; present study).