Robbea judithae sp.nov.

ZooBank registration: http://zoobank.org: urn:lsid:zoobank. org:act: EB683064-846B-4747-8431-E10DD10EFC2.

Type location: Carrie Bow Cay, Belize; back-reef sand patch north of the island, 2 m depth. Coordinates: 16.803371 N, 88.082003 W.

Type material: One holotype (NHMW-ZOO-EV-M-5863), four paratypes male (NHMW-ZOO-EV-M-5864/1-4), three paratypes female (NHMW-ZOO-EV-M-5865/1-3). Collection date: April 2013. Collector: J.A. Ott.

Other material: Several specimens in J.A. Ott collection.

Distribution: Regularly in all shallow, subtidal, back-reef sands around Carrie Bow Cay.

Etymology: The species is dedicated to Judith Zimmermann, who contributed significantly to the study of Stilbonematinae .

Description: With the characters of the genus. Measurements see Supporting Information, Table S2.

Large, slender species (Figures 3–5), live specimens with conspicuously dark-coloured GSOs. Males with prominent ventral GSOs in post-pharyngeal region that protrude as 16–18 bumps when the worm’s body is bent ventrally. Cephalic capsule extending over 55–60% of corpus. Corpus of the pharynx less than 25% of pharynx length, isthmus very long occupying 61–67% of pharynx, bulbus small, glandular. Tail conical with rounded tip. Symbiotic bacteria short rods, 2 × 1µm.