Pilumnus spinifer H. Milne Edwards, 1834

Guerao, Guillermo, Abelló, Pere & Díaz, David, 2005, The complete larval development of the crab Pilumnus spinifer (Brachyura: Xanthoidea: Pilumnidae) reared in the laboratory, Journal of Natural History 39 (35), pp. 3187-3216 : 3189-3207

publication ID

https://doi.org/ 10.1080/00222930500256235

persistent identifier

https://treatment.plazi.org/id/03BD5C07-FFEC-FFA6-FE0B-CB434DB8FAA2

treatment provided by

Felipe

scientific name

Pilumnus spinifer H. Milne Edwards, 1834
status

 

Pilumnus spinifer H. Milne Edwards, 1834 View in CoL

( Figures 1–17 View Figure 1 View Figure 2 View Figure 3 View Figure 4 View Figure 5 View Figure 6 View Figure 7 View Figure 8 View Figure 9 View Figure 10 View Figure 11 View Figure 12 View Figure 13 View Figure 14 View Figure 15 View Figure 16 View Figure 17 )

Gourret 1884, p. 17, Plate 2, Figures 8–11 View Figure 8 View Figure 9 View Figure 10 View Figure 11 , zoea I.

First zoea

Size. RDL: 0.87–0.90 mm; CL: 0.50–0.55 mm; CW: 0.50–0.57 mm.

Carapace ( Figure 1A, B View Figure 1 ). Globose, smooth, without tubercles. Dorsal spine present, welldeveloped, markedly curved posteriorly, with sparsely minute protuberances ( Figure 1A 1 View Figure 1 ). Rostral spine smooth, thin and shorter than dorsal spine, longer than antennule (excluded aesthetascs) and shorter than antenna ( Figure 1B View Figure 1 ). A single thin and short lateral spine. A pair of simple setae on posterodorsal region. Posterior and ventral margin without setae. Posterolateral margin of carapace with numerous acute small spines ( Figure 1A View Figure 1 2 View Figure 2 ). Eyes sessile.

Antennule ( Figure 3A View Figure 3 ). Uniramous. Endopod absent. Exopod unsegmented with four terminal aesthetascs and one terminal minute seta.

Antenna ( Figure 4A View Figure 4 ). Longer than rostral spine. Protopodal process and exopod approximately equal in length. Protopodal process with two rows of spines of different size along distal half. Exopod unsegmented with one long and one smaller seta arising near mid-length and two rows of spines of different size along distal half. Endopod absent.

Mandible. Incisor and molar processes differentiated. Endopod palp absent. Maxillule ( Figure 6A View Figure 6 ). Exopod and epipod seta absent. Coxal endite with seven setae. Basial endite with five setae. Endopod two-segmented, with one seta on proximal segment and six setae on distal segment (arranged as 2 + 2 + 2).

Maxilla ( Figure 7A View Figure 7 ). Coxal endite bilobed, with 5 + 4 setae. Basial endite bilobed with 5 + 4 setae. Endopod unsegmented, bilobed, with three long setae on proximal and five (two subterminal and three terminal) on distal lobe. Scaphognathite (exopod) with four plumose marginal setae and a long distal stout process.

First maxilliped ( Figure 9A View Figure 9 ). Coxa without seta. Basis with 10 medial setae arranged 2 + 2 + 3 + 3 on inner side. Endopod five-segmented, with 3, 2, 1, 2, 5 (one subterminal and four terminal) setae. Exopod two-segmented; distal segment with four long plumose natatory setae.

Second maxilliped ( Figure 10A View Figure 10 ). Coxa without setae. Basis with four medial setae arranged 1 + 1 + 1 + 1. Endopod three-segmented, with 1, 1, 6 setae. Exopod two-segmented; distal segment with four long plumose natatory setae.

Third maxilliped. Present as bilobed small bud.

First pereiopod. Present as small bud.

Abdomen ( Figures 14A, B View Figure 14 , 15A View Figure 15 ). Five somites. Somites 2 and 3 with one pair of dorsolateral processes. Dorsolateral process on somite 2 stout and blunt, with tip directed anteriorly; process on somite 3 sharp, with posteriorly pointed tip, with relative size decreasing throughout the stages. Somites 3–5 with short posterolateral processes. Somites 2–5 with one pair of posterodorsal simple setae. Posterior margin of somites 2–5 spinulate.

Pleopods. Pleopod buds absent.

Telson ( Figures 14A, C View Figure 14 , 15A View Figure 15 ). With two lateral spines (one large and one very small), and one dorsomedial spine. Furca large, with a medial V-shaped cleft on posterior margin; with three pairs of serrate setae on posterior margin. Furca and large lateral spine strongly spinulated. F/OLS53.3; F/DS56.8; F/OLM518.8.

Second zoea

Size. RDL: 1.05–1.07 mm; CL: 0.67–0.7 mm; CW: 0.62–0.65 mm.

Carapace ( Figure 1C View Figure 1 ). Two pairs of anterodorsal setae. Each lateroventral margin with three setae. Eyes stalked.

Antennule ( Figure 3B View Figure 3 ). Exopod with five aesthetascs and one minute seta. Antenna ( Figure 4B View Figure 4 ). Endopod bud present.

Mandible. Unchanged.

Maxillule ( Figure 6B View Figure 6 ). Basial endite with eight (1 + 7) setae. Exopod plumose seta and epipod seta present.

Maxilla ( Figure 7B View Figure 7 ). Basial endite with 6 + 5 setae. Scaphognathite with 10–11 plumose marginal setae, and without the long setose posterior process present in zoea I.

First maxilliped. Exopod distal segment with six long plumose natatory setae.

Second maxilliped. Exopod distal segment with six long plumose natatory setae.

Third maxilliped. Biramous.

Pereiopods ( Figure 12A View Figure 12 ). All present, unsegmented. First pereiopod distally bilobed.

Abdomen ( Figures 14D View Figure 14 , 15B View Figure 15 ). First somite with two long mid-dorsal setae.

Pleopods. Absent.

Telson ( Figures 14D View Figure 14 , 15B View Figure 15 ). F/OLS53.1; F/DS59.7; F/OLM546.5.

Third zoea

Size. RDL: 1.25–1.30 mm; CL: 0.75–0.76 mm; CW: 0.70–0.72 mm.

Carapace ( Figure 1D View Figure 1 ). Two pairs of anterodorsal setae. Dorsal spine with two pairs of setae. Each lateroventral margin with six setae.

Antennule ( Figure 3C View Figure 3 ). Small endopod bud present. Exopod with one additional subterminal aesthetasc.

Antenna ( Figure 4C View Figure 4 ). Endopod bud elongated, approximately half the length of exopod.

Mandible. Unchanged.

Maxillule ( Figure 6C View Figure 6 ). Basial endite with nine (1 + 8) setae.

Maxilla ( Figure 7C View Figure 7 ). Basial endite with 6 + 6 setae. Scaphognathite with 18 plumose marginal setae.

First maxilliped ( Figure 9B View Figure 9 ). Endopod distal segment with six setae. Exopod distal segment with eight long plumose natatory setae.

Second maxilliped. Exopod distal segment with eight long plumose natatory setae.

Third maxilliped ( Figure 11A View Figure 11 ). Biramous, unsegmented; epipod present, rudimentary.

Pereiopods ( Figure 12B View Figure 12 ). Unsegmented. Chelipeds bilobed, extending beneath carapace.

Abdomen ( Figures 14E View Figure 14 , 15C View Figure 15 ). Somite 6 now present, without setae. First somite with four dorsomedial setae and one medial posterodorsal seta.

Pleopods ( Figure 15C View Figure 15 ). Present as buds on somites 2–5, endopods absent.

Telson ( Figures 14E View Figure 14 , 15C View Figure 15 ). F/OLS52.8; F/DS512.5; F/OLM553.5.

Fourth zoea

Size. RDL: 1.45–1.47 mm; CL: 0.87–0.90 mm; CW: 0.80–0.82 mm.

Carapace ( Figure 2A, B View Figure 2 ). Three pairs of anterodorsal setae. Dorsal spine with three pairs of setae. Each lateroventral margin with nine setae.

Antennule ( Figure 3D View Figure 3 ). Biramous, endopod bud developed without setae. Exopod with proximal minute seta, and five (1 + 4) subterminal and five terminal aesthetascs.

Antenna ( Figure 4D View Figure 4 ). Endopod approximately three-quarters length of exopod, extending beyond the exopod setae.

Mandible ( Figure 5A View Figure 5 ). Palp bud present.

Maxillule ( Figure 6D View Figure 6 ). Coxal endite with eight to nine setae. Basial endite with 10–11 setae.

Maxilla ( Figure 7D View Figure 7 ). Scaphognathite with 21–22 plumose marginal setae.

First maxilliped. Exopod distal segment with 10 long plumose natatory setae.

Second maxilliped ( Figure 10B View Figure 10 ). Exopod distal segment with 10 long plumose natatory setae.

Third maxilliped ( Figure 11B View Figure 11 ). Endopod and exopod slightly segmented.

Pereiopods ( Figure 12C View Figure 12 ). Incipient segmentation.

Abdomen ( Figures 14F View Figure 14 , 16A View Figure 16 ). Unchanged.

Pleopods ( Figure 16A View Figure 16 ). Pleopod buds elongated, endopods present.

Telson ( Figures 14F, G View Figure 14 , 16A View Figure 16 ). With two dorsal setae. F/OLS52.8; F/DS514.2; F/ OLM564.

Megalopa

Size. CL: 1.20–1.25 mm; CW: 0.85–0.87 mm.

Carapace ( Figure 2C, D View Figure 2 ). Longer than broad. Rostrum deflected obliquely downwards; frontal region moderately broadened with margins expanded and slightly acute. Without spines or tubercles. Setal arrangement as figured.

Antennule ( Figure 3E View Figure 3 ). Peduncle three-segmented, with 4, 2, 0 setae, respectively. Endopod unsegmented with two subterminal and four terminal setae. Exopod four-segmented, with 0, 6–7, 6, 4 aesthetascs and 0, 0, 3, 2 (one subterminal and one terminal) setae.

Antenna ( Figure 4E View Figure 4 ). Peduncle three-segmented, with 2, 1, 1–2 setae. Flagellum sevensegmented, with 0, 0, 0, 5, 0, 3, 4 setae.

Mandible ( Figure 5B View Figure 5 ). Palp two-segmented, with seven setae on distal segment.

Maxillule ( Figure 6E View Figure 6 ). Coxal endite with 14 setae. Basial endite with 18 (16 + 2) setae. Endopod three-segmented, with 1, 1, 3 setae.

Maxilla ( Figure 8 View Figure 8 ). Coxal endite bilobed, with 8 + 4 setae. Basial endite bilobed with 7 + 7– 8 setae. Endopod unsegmented, with two setae on outer basal margin. Scaphognathite with 38–39 plumose marginal setae and four lateral setae.

First maxilliped ( Figure 9C View Figure 9 ). Epipod with five long setae. Coxal endite with seven to eight setae. Basial endite with 14 setae. Endopod unsegmented with two subterminal and two terminal setae. Exopod three-segmented, proximal segment with two distal setae, distal segment with five long terminal plumose setae.

Second maxilliped ( Figure 10C View Figure 10 ). Epipod rudimentary. Coxa and basis not differentiated, with one seta. Endopod four-segmented with 2, 1–2, 5, 7 setae. Exopod three-segmented; proximal segment with one medial seta, distal segment with five terminal plumose setae.

Third maxilliped ( Figure 11C View Figure 11 ). Epipod with 13 setae (five pappose setae + eight long simple setae). Coxa with 14 setae. Basis with four setae. Endopod five-segmented, with 12–14, 10, 6, 10, 6 setae. Exopod two-segmented; proximal segment with one seta and distal segment with three to four long terminal plumose setae.

Pereiopods ( Figure 13A–H View Figure 13 ). All articles well differentiated. Pereiopod 1 (cheliped) without coxal spine, with two ischial spines (one minute) and one meral spine ( Figure 13A View Figure 13 ); pereiopods 2–3 with one coxal and one ischial spine ( Figure 13 B, C View Figure 13 ); pereiopod 4 with one coxal spine ( Figure 13D View Figure 13 ). Dactylus of pereiopods 2–4 with three strong serrated spines ( Figure 13B–D, F, G View Figure 13 ) on inner margin. Dactylus of pereiopod 5 with two long subterminal setae of diferent size ( Figure 13H View Figure 13 ). Setation as figured.

Sternum ( Figure 13I View Figure 13 ). Maxillipeds and cheliped sternites fused with six setae plus one pair of small processes. All sternal sutures are interrupted medially.

Abdomen ( Figures 14H View Figure 14 , 16B View Figure 16 ). Six somites present; somite 1 with 12 setae; somite 2 with 10 setae; somites 3 and 4 with 12 setae; somite 5 with 14 setae; somite 6 with four setae. Posterolateral processes of somites 3–5 acute; processes of somite 5 overlapping with somite 6.

Pleopods ( Figure 17A, B View Figure 17 ). Somites 2–5 each with one pair of biramous pleopods. Endopod unsegmented with 3, 2, 2, 2 subterminal hooks on internal margin; exopod unsegmented with 13, 13, 12, 10 long marginal plumose natatory setae, respectively, for each pair of pleopods.

Uropods ( Figure 17C View Figure 17 ). Uropods two-segmented on somite 6, proximal segment with one, and distal segment with six long plumose setae.

Telson ( Figures 14H View Figure 14 , 16B View Figure 16 ). Posterior margin rounded, with two dorsal and two ventral setae.

Kingdom

Animalia

Phylum

Arthropoda

Class

Malacostraca

Order

Decapoda

Family

Pilumnidae

Genus

Pilumnus

Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF