Hyppolyte leptocerus (Heller, 1863)

Guerao, Guillermo, Hernández, Esteban & Urzúa, Ángel, 2011, Early zoeal development of the shrimp Hippolyte leptocerus (Decapoda, Caridea, Hippolytidae), Zootaxa 2988, pp. 53-65 : 54-62

Hyppolyte leptocerus (Heller, 1863)

( Figs 1 B–7)

Zoea I. Size. TL= 1.33–1.36 mm; CL = 0.49–0.51 mm.

Carapace ( Figs. 2 A,B). Eyes sessile, with a single minute median tubercle. Rostrum long, directed slightly downward, exceeding the anterior margin of scaphocerite. Pterygostomial spine present with 2 small spines posteriorly. Supraorbital spines absent.

Antennule ( Fig. 2 C). Peduncle unsegmented, without setae. Inner flagellum (endopod) represented by a long plumose seta; outer flagellum unsegmented with 4 terminal aesthetascs.

Antenna ( Fig. 2 D). Birramous, peduncle (protopod) with a distal spine on inner magin. Endopod slender unsegmented, slightly more than ½ length of exopod and with 6 spines on inner side. Exopod (scaphocerite) 3-segmented with 10 (5, 1, 4) plumose setae, plus 1 short simple seta on the distal segment.

Mandible ( Fig 2 E, F). Asymmetrical; incisor and molar processes differentiated. Mandibular palp absent. Left mandible with lacinia mobilis near incisor process. Rigth mandible with 2 teeth between incisor and molar processes.

Maxillule ( Fig. 2 G). Coxal endite with 7 setae and basial endite with 7 spinous setae. Endopod unsegmented, with 5 terminal setae. Outer plumose seta (exopodal seta) present.

Maxilla ( Fig. 2 H). Coxa bilobed, with 7–8 + 3–4 setae. Basial endite bilobed with 5 + 4 setae. Endopod unsegmented and bilobed with 3 + 5 setae. Exopod (scaphognathite) with 5 marginal plumose setae.

First maxilliped (Fig, 3A). Coxa and basis with 5 and 12 setae on inner margin respectively. Endopod 4-segmented, with 3, 1, 2, 4(1 + 3) setae. Exopod incompletely 3-segmented with 4 long plumose natatory setae (one subterminal and 3 terminal).

Second maxilliped ( Fig. 3 B). Coxa and basis with one and 8 setae on inner margin respectively. Endopod 4- segmented, with 3, 2, 2, 5(1 + 4) setae. Exopod incompletely segmented with 5 long plumose natatory setae (2 subterminal and 3 terminal).

Third maxilliped ( Fig. 3 C). Protopod with 2 inner setae. Endopod 4-segmented, with 1, 0, 2, 4(1 + 3) seate. Exopod incompletely segmented with 5 long plumose natatory setae (2 subterminal and 3 terminal).

Pereiopods. Absent.

Pleon ( Figs. 2 A, B). Five somites plus telson, without pleopods and uropods. Pair of posterolateral spines on somite 5. Anal papilla present.

Telson ( Figs. 2 A,B, 3D). Triangular with a shallow median cleft posteriorly and 7 + 7 setae of different sizes, two outer pairs of setae feathered only on their inner side. Minute spinules present on posterior margin.

Zoea II. Size. TL= 1.55–1.57 mm; CL= 0.55–0.60 μm

Carapace ( Figs. 4 A, B). Eyes stalked.

Antennule ( Fig. 4 C). Peduncle incompletely segmented, with 2 distal setae on basal segment. Distal segment with 4 setae.

Antenna ( Fig. 4 D). Scaphocerite with tendency to lose segmentation. Otherwise unchanged.

Mandible. Unchanged

Maxillule ( Fig. 4 E). Unchanged.

Maxilla ( Fig. 4 F). Coxa bilobed, with 8 + 4 setae. Basial endite bilobed with 5 + 5 setae. Exopod (scaphognathite) with 7 plumose marginal setae.

First maxilliped ( Fig. 5 A). Basis with 14 setae on inner margin. Exopod with one subterminal and 4 terminal long plumose natatory setae.

Second maxilliped ( Fig. 5 B). Endopod 5-segmented, with 2, 2, 0, 2, 6(1 + 5) setae. Exopod with 2 subterminal and 4 terminal long plumose natatory setae.

Third maxilliped ( Fig. 5 C). Protopod (basis) with 3 inner setae. Endopod 5-segmented, with 1, 1, 0, 2, 5(1 + 4) seate. Exopod with 2 subterminal and 4 terminal long plumose natatory setae

Pereiopods. First pereiopod present as a bud.

Pleon ( Figs. 4 A, B). Unchanged.

Telson ( Figs. 4 A,B, 5D). Posterior margin with 8 + 8 setae of different sizes. Outer pair of setae feathered only on their inner side.

Zoea III. Size. TL= 1.70–2.00 mm; CL = 0.65–0.70 mm.

Carapace ( Figs. 6 A, B, C). Anteroventral margin with 3 small spines posteriorly to pterygostomial spine.

Antennule ( Fig. 6 D). Peduncle 3-segmented. Proximal segment bearing a small lateral spine and without setae; second segment with 3 + 2 setae; distal segment with 5 setae. Flagellum with 2 aesthetascs and one seta.

Antenna ( Fig. 6 E). Exopod (scaphocerite) unsegmented, with a distolateral spine.

Maxillule ( Fig. 6 F). Basial endites with 8 setae.

Maxilla ( Fig. 6 G). Coxa bilobed, with 10 + 4 setae. Basial endite bilobed with 6 + 7 setae. Exopod (scaphognathite) with 10 plumose marginal setae.

First maxilliped ( Fig. 7 A). Basis with 15 setae on inner margin. Endopod 4-segmented, with 3, 1, 3, 4 setae.

Second maxilliped ( Fig. 7 B). Endopod 5-segmented, with 2, 1, 0, 2, 6(1 + 5) setae.

Third maxilliped ( Fig. 7 C). Unchanged.

First pereiopod ( Fig. 7 D). Birramous. Endopod unsegmented and non-chelated with 3 distal setae. Exopod with 2 subterminal and 4 terminal setae.

Second and third pereiopods. Present as a bud.

Pleon ( Figs. 6 A, B). 6-segmented. Sixth pleonite with a posterolateral spine.

Telson ( Fig. 6 A,B, 7E). Separate from pleonite 6.

Uropods ( Fig. 7 F). Birramous, exopod with 7 plumose setae. Endopod shorter than exopod with 2 distal simple setae.

Figures

FIGURE 1. Hippolyte leptocerus. A, adult female, lateral view; B, zoea I, dorsal view. Scale bar of A = 3 mm; of B = 500 μm.

FIGURE 2. Hippolyte leptocerus. Zoea I. A, dorsal view; B, lateral view; C, antennule; D, antenna; E, left mandible; F, right mandible; G, maxillule; H, maxilla. Scale bars 200 μm.

FIGURE 3. Hippolyte leptocerus. Zoea I. A, first maxilliped; B, second maxilliped; C, third maxilliped; D, telson. Scale bars 200 μm.

FIGURE 4. Hippolyte leptocerus. Zoea II. A, dorsal view; B, lateral view; C, antennule; D, antenna; E, maxillule; F, maxilla. Scale bars 200 μm.

FIGURE 5. Hippolyte leptocerus. Zoea II. A, first maxilliped; B, second maxilliped; C, third maxilliped; D, telson. Scale bars 200 μm.

FIGURE 6. Hippolyte leptocerus. Zoea III. A, dorsal view; B, lateral view; C, carapace, anteroventral region; D, antennule; E, antenna; F, maxillule; G, maxilla. Scale bars of 200 μm.

FIGURE 7. Hippolyte leptocerus. Zoea III. A, first maxilliped; B, second maxilliped; C, third maxilliped; D, first pereiopod; E, telson; F, uropod. Scale bars 200 μm.