Nymphon, J. C. Fabricius, 1794

Staples, David A., 2019, Pycnogonids (Arthropoda, Pycnogonida) from the Southwest Indian Ridge, Zootaxa 4567 (3), pp. 401-449 : 412-413

Nymphon species indeterminate

Figure 6 A–C

Material examined. One subadult (NHMUK 2018.12), Southwest Indian Ocean, Middle of What Seamount, stn 6.4, event K3, 0.5 cm horizon, depth 1010 m, collector Lucy Woodall.

Description. Trunk smooth ( Fig. 6A ), segmentation between trunk segments 3 and 4 not evident; lateral

processes separated by about own diameter. Ocular tubercle conical, four eyes, pigmented. Chela fingers crossing at tip, immoveable finger with 8 teeth, moveable finger with 7 teeth. Palp segmentation incomplete. Ovigers consist of two ventral buds. Third leg ( Fig. 6B ) with several long spines atop small bosses, tibia 2 longer than tibia1 or femur, coxa 2 one-third longer than coxa 1 or 3, coxa 2 and 3 equal, tarsus short, no raised propodal heel, sole with six spines, auxiliary claws slender, half length of main claw.

Remarks. In the absence of complete segmentation of the palps and ovigers, determination of the family is uncertain but based on general habitus I have assigned this specimen to the genus Nymphon . This immature specimen was retrieved from sediment samples post-voyage but there are few characters evident that would distinguish the species in its adult form.

The lateral processes on the right side of the trunk appear to be more widely separated due to the flexing of the body to the right side.

Figures

FIGURE 6 Nymphon species indeterminate. A, trunk, dorsal view; B, third leg; C, palps, chela and proboscis ventral view.