Nanocassiope granulipes ( Sakai, 1939 )

Ko, Hyun Sook & Clark, Paul F., 2002, The zoeal development of Nanocassiope granulipes (Sakai, 1939) (Crustacea: Decapoda: Brachyura: Xanthidae) described from laboratory-reared material, Journal of Natural History 36 (12), pp. 1463-1488 : 1465-1479

Nanocassiope granulipes ( Sakai, 1939)

(gures 1–13)

Zoea I

Size. Carapace length 0.46 Ô 0.03 mm. Distance from tip of dorsal spine to tip of rostral spine 1.50 Ô 0.03 mm.

Carapace (gure 1a). Dorsal spine long, distally curved and spinulate and longer than rostral spine; rostral spine straight with three small spines distally and shorter than antennal protopod; lateral spines present and short; anterodorsal setae absent; one pair of posterodorsal setae present; each ventral margin without setae; eyes sessile.

Antennule (gure 4a). Uniramous; endopod absent; exopod unsegmented with three long (two stout1 one thinner) aesthetascs, one short, slender aesthetasc and one small seta, all terminal.

Antenna (gure 5a, b). Protopod longer than rostral spine and distally spinulate; with a minute protopodal spine; exopod ca 12% length of protopod with one short terminal seta.

Mandible. Asymmetrical; right molar with two teeth and left molar with one tooth, con uent with incisor process; endopod palp absent.

Maxillule (gure 6a). Coxal epipod absent, endite with seven terminal setae; basial endite with ve setal processes; endopod two-segmented, proximal segment with one seta, distal segment with six (two subterminal1 four terminal) setae; exopod seta absent.

Maxilla (gure 7a). Coxal endite bilobed with 41 4 setae; basial endite bilobed with 51 4 setae; endopod bilobed with 31 5 (two subterminal1 three terminal) setae; exopod (scaphognathite) margin with four plumose setae plus distal stout process.

First maxilliped (gure 8a). Coxa with one seta; basis with 10 setae arranged 2, 2, 3, 3; endopod ve-segmented with 3, 2, 1, 2, 5 (one subterminal1 four terminal) setae, respectively; exopod two-segmented, distal segment with four terminal natatory plumose setae.

Second maxilliped (gure 9a). Coxa without seta; basis with four setae; endopod three-segmented, with 1, 1, 5 (two subterminal1 three terminal) setae, respectively; exopod two-segmented, distal segment with four terminal natatory plumose setae.

Third maxilliped. Absent.

Pereiopods. Absent.

Abdomen (gures 11a, 12a). Five somites; somite 2 with a pair of lateral processes directed laterally; somite 3 with a pair of lateral processes directed posteriorly; somites 3–5 with posterolateral processes; somites 2–5 with one pair of posterodorsa l setae; pleopods absent.

Telson (gures 11a, 12a, 13a). Each fork long and not spinulate, with one stout lateral spine, one minute lateral seta and one stout dorsomedial spine; posterior margin with three pairs of stout spinulate setae.

Zoea II

Size. Carapace length 0.52 Ô 0.05 mm. Distance from tip of dorsal spine to tip of rostral spine 1.68 Ô 0.09 mm.

Carapace (gures 1b, 3a). Dorsal spine with one pair of setae proximally; two pairs of anterodorsal setae present; each ventral margin with one plumose anterior seta; eyes stalked; otherwise unchanged.

Antennule (gure 4b). Exopod now with ve long (three stout1 two thinner) aesthetascs, otherwise unchanged.

Antenna (gure 5c, d). Minute protopodal spine now absent; exopod now ca 4% length of protopod; otherwise unchanged.

Mandible. Unchanged.

Maxillule (gure 6b). Basial endite with eight setal processes; exopod plumose seta now present; otherwise unchanged.

Maxilla (gure 7b). Exopod (scaphognathite) margin with 11 plumose setae and distal, stout process no longer prominent; otherwise unchanged.

First maxilliped (gure 8b). Exopod distal segment now with six terminal natatory plumose setae; otherwise unchanged.

Second maxilliped (gure 9b). Exopod distal segment now with seven terminal natatory plumose setae; otherwise unchanged.

Third maxilliped. Developing.

Pereiopods. Developing.

Abdomen (gures 11b, 12b). Somites 3–5 with longer posterolateral processes; otherwise unchanged.

Telson (gures 11b, 12b, 13b). Unchanged.

Zoea III

Size. Carapace length 0.80 Ô 0.02 mm. Distance from tip of dorsal spine to tip of rostral spine 2.54 Ô 0.09 mm.

Carapace (gures 2a, 3b). Dorsal spine now with two pairs of setae proximally; ve pairs of anterodorsal setae; each ventral margin with one plumose anterior seta plus ve posterior setae; otherwise unchanged.

Antennule (gure 4c). Exopod now with one subterminal aesthetasc; otherwise unchanged.

Antenna (gure 5e, f). Endopod bud present; otherwise unchanged.

Mandible. Unchanged.

Maxillule (gure 6c). Coxal endite now with eight terminal setae; basial endite with nine setal processes; otherwise unchanged.

Maxilla (gure 7c). Coxal endite bilobed now with 51 4 setae; basial endite bilobed with 51 5 setae; exopod (scaphognathite) margin with 19 plumose setae; otherwise unchanged.

First maxilliped (gure 8c). Coxa with epipod bud present; endopod terminal segment with six (two subterminal1 four terminal) setae; exopod distal segment now with eight terminal natatory plumose setae; otherwise unchanged.

Second maxilliped (gure 9c). Exopod distal segment now with nine terminal natatory plumose setae; otherwise unchanged.

Third maxilliped (gure 10a). Biramous; endopod longer than exopod.

Pereiopods (gure 10c). Rudimentary, undiVerentiated into segments; cheliped bilobed.

Abdomen (gures 11c, 12c). Now with six somites; somite 1 with one pair of dorsomedial setae; somites 3–5 with slightly longer posterolateral processes; pleopod buds present but without endopod buds; otherwise unchanged.

Telson (gures 11c, 12c, 13c). Posterior margin with three pairs of stout spinulate setae plus one pair of small setae; otherwise unchanged.

Zoea IV

Size. Carapace length 1.13 Ô 0.04 mm. Distance from tip of dorsal spine to tip of rostral spine 2.92 Ô 0.12 mm.

Carapace (gures 2b, 3c). Seven pairs of anterodorsal setae; each ventral margin with one plumose anterior seta plus eight posterior setae; otherwise unchanged.

Antennule (gure 4d). Biramous; endopod bud present; exopod with four rows of subterminal aesthetascs arranged 2, 4, 2, 1 and in the terminal position, ve long (three stout1 two slender), one short slender aesthetasc and one small seta.

Antenna (gures 5g, h). Endopod developing; otherwise unchanged.

Mandible (gure 10e). Endopod palp present.

Maxillule (gure 6d). Coxal epipod seta now present; endite now with 11 terminal setae; basial endite with 13 setal processes; otherwise unchanged.

Maxilla (gure 7d). Coxal endite bilobed now with 61 4 setae; basial endite bilobed with 61 7 setae; exopod (scaphognathite) margin with 29 plumose setae; otherwise unchanged.

First maxilliped (gure 8d). Coxa with epipod bud more developed and now with two setae; exopod distal segment now with nine terminal natatory plumose setae; otherwise unchanged.

Second maxilliped (gure 9d). Exopod distal segment now with 11 terminal natatory plumose setae; otherwise unchanged.

Third maxilliped (gure 10b). Epipod now present; arthrobranch gill present; endopod and exopod developing.

Pereiopods (gure 10d). Some segmental diVerentiation into segments.

Abdomen (gures 11d, 12d). Somite 1 with three dorsal medial setae; somites 3–5 with slightly longer posterolateral processes; pleopods 1–4 with endopod buds; otherwise unchanged.

Telson (gures 11d, 12d, 13d). Dorsal medial surface with one pair of setae; posterior margin with three pairs of stout spinulate setae plus two pairs of small setae; otherwise unchanged.