Atergatis subdentatus ( de Haan, 1835 )

Clark, Paul F. & Ng, Peter K. L., 2004, Atergatis Subdentatus (De Haan, 1835), Atergatopsis Germaini A. Milne Edwards, 1865 And Platypodia Eydouxi (A. Milne Edwards, 1865) (Crustacea: Decapoda: Xanthoidea: Xanthidae: Zosiminae) - First Stage Zoeal Descriptions With Implications For The Subfamily, Raffles Bulletin of Zoology 52 (2), pp. 563-592 : 569

Atergatis subdentatus ( de Haan, 1835)

( Figs. 5-8 )

Description. – Carapace ( Figs. 5a, b ): dorsal spine long, curved distally and approximately twice the length of the rostral spine; rostral spine just shorter in length than the antennal protopod and distally spinulate; lateral spines present and straight; 1 pair of posterodorsal setae; ventral margin without setae; eyes sessile.

Antennule ( Fig. 5c ): uniramous, endopod absent; exopod unsegmented with 2 broad, long and 2 slender, shorter, terminal aesthetascs plus 1 terminal seta.

Antenna ( Fig. 5d ): protopodal process distally multispinulate, just longer in length than rostral spine; endopod reduced to small spine; exopod ca. 16% length of protopod, possessing 3 (1 long subterminal, 2 unequal terminal) setae.

Mandible: palp absent.

Maxillule ( Fig. 6a ): epipod seta absent; coxal endite with 7 setae; basial endite with 5 setal processes and 2 small teeth; endopod 2-segmented, proximal segment with 1 seta; distal segment with 6 (2 subterminal, 4 terminal) setae; exopod seta absent.

Maxilla ( Fig. 6b ): coxal endite bilobed with 4+4 setae; basial endite bilobed with 5+4 setae; endopod bilobed, with 3+5 (2 subterminal, 3 terminal) setae; exopod (scaphognathite) margin with 4 setae and 1 long stout distal process.

First maxilliped ( Fig. 7a): coxa with 1 seta; basis with 10 setae arranged 2,2,3,3; endopod 5-segmented with 3,2,1,2,5 (1 subterminal, 4 terminal) setae respectively; exopod 2- segmented, distal segment with 4 long terminal plumose natatory setae.

Second maxilliped ( Fig. 7b): coxa without setae; basis with 4 setae arranged 1,1,1,1; endopod 3-segmented, with 1,1,6 (3 subterminal, 3 terminal) setae respectively; exopod 2- segmented, distal segment with 4 long terminal plumose natatory setae.

Third maxilliped: absent.

Pereiopods: absent.

Abdomen ( Figs. 8a, b ): 5 somites; somite 2 with 1 pair of dorsolateral processes directed anteriorly; somite 3 with 1 pair of dorsolateral processes directed ventrally; somites 1- 2 with rounded posterolateral processes and 3-5 with short posterolateral spinous processes; somite 1 without setae; somites 2-5 with 1 pair of posterodorsal setae; pleopod buds absent.

Telson ( Figs. 6c , 8a, b ): each fork long, gradually curved distally; 1 large and 1 finer lateral spine; 1 large dorsal medial spine; posterior margin with 3 pairs of stout spinulate setae.

Figures

Fig. 5. Atergatis subdentatus (de Haan, 1835) first stage zoea; a) anterior view of carapace; b) antennule; c) antenna; d) rostral spine.

Fig. 6. Atergatis subdentatus (de Haan, 1835) first stage zoea; a) maxillule; b) maxilla; c) telson.

Fig. 8. Atergatis subdentatus (de Haan, 1835) first stage zoea; a) dorsal view of abdomen; b) lateral view of abdomen.