Hamatipeda prolata, Segadilha & Serejo & Błażewicz, 2019
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publication ID |
https://doi.org/ 10.11646/zootaxa.4661.2.4 |
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publication LSID |
lsid:zoobank.org:pub:497C5D82-320D-4C6A-A795-93C03C7A5EAC |
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persistent identifier |
https://treatment.plazi.org/id/C77087F7-BE2E-1D6A-FF1A-FE99A1AB7083 |
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treatment provided by |
Plazi |
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scientific name |
Hamatipeda prolata |
| status |
sp. nov. |
Hamatipeda prolata sp. nov. Segadilha & Błażewicz
LSID urn:lsid:zoobank.org:act:47DDBC56-3B8A-4F32-AFB7-7FC0D3B9B906
( Figs. 1–3 View FIGURE 1 View FIGURE 2 View FIGURE 3 )
Material examined. Holotype: female non-ovigerous, length 4.0 mm ( MZUSP 38956 View Materials ), Sta AMB 5 View Materials B6 R1.
Paratypes: eleven females ( MZUSP 38966 View Materials ), one dissected length 2.8 mm Sta AMB 5 View Materials A6 R1.
Additional material: one female non-ovigerous, length 3.2 mm ( MZUSP 34485) dissected, Sta HAB 9 CANAC 7; female non-ovigerous ( MZUSP 34475) Sta HAB 9 CANG 8; six females ( MZUSP 22906) Sta HAB 11 E4 R2; five females ( MZUSP 32894) Sta HAB 11 E4 R3; fifteen females (one ovigerous) ( MZUSP 32895) Sta HAB 11 E4 R2; three females ( MZUSP 32896) Sta HAB 13 I5 R1; three females ( MZUSP 32897) Sta HAB 16 E4 R1; ten females ( MZUSP 32898) Sta HAB 16 E4 R1; three females ( MZUSP 32899) Sta HAB 16 H5 R2; five man- cae ( MZUSP 32908) Sta HAB 9 I 7 R2; one female ( MZUSP 34476) Sta HAB 9 CANAC 7; one female ( MZUSP 34478) Sta HAB 16 E4; one female ( MZUSP 34479) Sta HAB 17 I4; one manca ( MZUSP 34480) Sta HAB 16 B3; one female and one manca ( MZUSP 34481) Sta HAB 9 CANAC 7; one female and one manca ( MZUSP 34482) Sta HAB 9 G7; one female ( MZUSP 34483) Sta HAB 9 CANAC 9; one neuter without pleopods ( MZUSP 34484) Sta HAB 17 I5; one female ( MOUFPE 15880) Sta B3 R3; one female ( MOUFPE 15896) Sta A9 R1; one female ( MNRJ 21315) Sta #44; fifteen females ( MNRJ 26489) Sta #1 C6 R2; one female ( MNRJ 26490) Sta #A3; five females ( MNRJ 26491) Sta #1 C6 R2; one female ( MNRJ 27356) Sta #54.
Diagnosis. Body about 15 times L:W; pereonite-1 more than twice L:W; pereonites 2 and 3 about three times L: W; antennule article-3 with two setae and aesthetasc very long, more than three times as long as article-3; pereopods 1–3 merus with ventrodistal spine; pereopod-1 carpus with ventrodistal spine; pereopods 2–3 merus with one and carpus with two spines; pereopod-2 propodus with ventrodistal spine; uropod exopod one-articled, 0.7 times as long as endopod; endopod two-articled.
Etymology. Prolatus (Latin) = elongated. The name reflects the pereonites 1–3, which are long and slender.
Description of female. Paratype dissected, length 3.2 mm ( MZUSP 34485). Body ( Figs. 1A, B View FIGURE 1 ) slender, about 15 times L:W. Cephalothorax rectangular, 1.7 times L:W, 0.9 times as long as pereonite-1, naked; eyes absent.
Pereonites 1–6: all rectangular, with lateral margins parallel, 2.3, 2.7, 2.9, 2.1, 1.5, 1.0 times L:W, respectively; pereonites 1–3 with four minute setae on proximal margin; pereonites 4–6 with minute setae on proximal and lateral margins.
Pleon ( Fig. 1A, B View FIGURE 1 ) 0.1 TBL, with five subequal pleonites, together shorter than cephalothorax; pleonite-5 with lateral seta. Pleotelson rectangular, 0.5 times L:W, with pair of simple and pair of penicillate setae distally.
Antennule ( Fig. 1C View FIGURE 1 ) shorter than cephalothorax (0.7 times L:W), with three articles; article-1 0.6 TL, 2.1 times L:W, two simple and five penicillate medial setae, one simple and three penicillate setae distally; article-2 0.7 times L:W, 0.2 times as long as article-1, with two simple and one penicillate setae distally; article-3 4.1 times L:W, three times as long as article-2, with six simple setae (two long, more than three times as long as article-3) and one long terminal aesthetasc.
Antenna ( Fig. 1D View FIGURE 1 ) of six articles; article-1 partly fused with cephalothorax; article-2 slender, 1.3 times L:W, with distal seta; article-3 0.7 times L:W, 0.5 times as long as article-2, with distal seta; article-4 3.9 times L:W, 3.9 times as long as article-3, with three simple and three penicillate setae distally and microtrichia on outer margin; article-5 three times L:W, 0.5 times as long as article-4, with distal seta; article-6 minute with five simple terminal setae.
Labrum ( Fig. 1E View FIGURE 1 ) rounded, hood-shaped, distally covered by minute setae. Mandibles ( Fig. 1F, G View FIGURE 1 ) with molar broad well-developed, longer than incisor, with irregular edge, without denticles. Left mandible ( Fig. 1F View FIGURE 1 ) incisor simple, lacinia mobilis well developed, distal margin with five teeth; right mandible ( Fig. 1G View FIGURE 1 ) incisor distally trun- cate and gently undulate, without lacinia mobilis. Labium ( Fig. 1H View FIGURE 1 ) with distolateral corner finely setose; outer lobe membranous. Maxillule ( Fig. 1I View FIGURE 1 ) endite with eight terminal spines (one short); palp not recovered. Maxilla ( Fig. 1J View FIGURE 1 ) oval. Epignath ( Fig. 1L View FIGURE 1 ) elongate, linguiform, naked. Maxilliped ( Fig. 2A View FIGURE 2 ) basis elongate, with distal seta shorter than endites; each endite with medial seta and microtrichia on outer corner, small gustatory cusp and seta on distal margin; palp with four articles; article-1 triangular, naked; article-2 with three inner and one outer setae; article-3 with four simple inner setae; article-4 with five serrate inner setae and one subdistal outer seta.
Cheliped ( Fig. 2B View FIGURE 2 ) slender, basis 2.2 times L:W with posterior lobe partly occluded by the lower part of the cephalothorax; merus triangular, with ventral seta; carpus stout, 1.6 times L:W, with two mid-ventral and two min- ute dorsal setae (distal and subproximal); propodus as long as carpus, about 2.6 times L:W, with two setae near dactylus insertion (inner and outer); fixed finger with two ventral setae, cutting edge poorly calcified, almost simple, with small subdistal protrusion and three inner setae; dactylus with proximal seta, slightly longer than fixed finger.
Pereopod-1 ( Fig. 2C View FIGURE 2 ) walking type; slender and longer than others; coxa with seta; basis 3.9 times L:W, with penicillate dorsal seta; ischium with ventral seta; merus 1.5 times L:W, with dorsodistal seta and distoventral seta and spine; carpus 1.8 times L:W, with two dorsodistal setae and ventrodistal spine and rod-like seta; propodus 2.2 times L:W, 0.9 times as long as merus and carpus combined, with two dorsodistal and one ventrodistal rod-like setae, with microtrichia along dorsal margin; dactylus 0.5 times as long as unguis, with subproximal seta reaching half of dactylus; dactylus and unguis combined 0.9 times as long as propodus.
Pereopod-2 ( Fig. 2D View FIGURE 2 ) walking type; coxa with seta; basis 3.1 times L:W, with penicillate dorsal seta; ischium with ventral seta; merus 1.3 times L:W, with spine and seta ventrodistally; carpus 1.3 times L:W, with dorsodistal seta and two spines ventrodistal; propodus 2.6 times L:W, 0.9 times as long as merus and carpus combined, with dorsodistal and ventrodistal spines; dactylus 0.6 times as long as unguis, with seta reaching half of unguis; dactylus and unguis combined 0.7 times as long as propodus.
Pereopod-3 ( Fig. 2E View FIGURE 2 ) similar to pereopod-2, except, basis 3.4 times L:W, naked; merus 1.1 times L:W; propodus with microtrichia.
Pereopod-4 ( Fig. 2F View FIGURE 2 ) clinging type; coxa absent; basis robust 2.4 times L:W, with long ventral penicillate seta; ischium with ventral seta; merus triangular about twice L:W, with two distoventral circumplumose spines; carpus 1.7 times L:W, with dorsodistal seta and, one circumplumose and two hook-like ventrodistal spines; propodus 2.6 times L:W, with penicillate mid-dorsal seta, serrate dorsodistal seta shorter than unguis (almost reaching distal mar- gin of dactylus), two distoventral circumplumose spines; dactylus three times as long as unguis, with microtrichia; unguis distally trifurcate; dactylus and unguis combined 0.5 times as long as propodus.
Pereopod-5 ( Fig. 2G View FIGURE 2 ) similar to pereopod-4, except: basis twice L:W; merus 1.1 times L:W.
Pereopod-6 ( Fig. 2H View FIGURE 2 ) similar to pereopod-5, except basis with penicillate seta on dorsal margin; merus 1.6 times L:W; carpus 1.4 times L:W; propodus about 2.3 times L:W, with three serrate dorsodistal setae shorter than unguis ( Fig. 2I View FIGURE 2 ), two ventrodistal circumplumose spines and microtrichia; dorsal penicillate seta on propodus not seen.
Pleopod ( Fig. 2J View FIGURE 2 ). All pleopods similar; basal article naked; exopod with seven plumose setae on outer margin and with plumose seta on inner margin; endopod with twelve plumose setae on outer margin; gap between proximal seta and other ventral setae in both rami.
Uropod ( Fig. 2L View FIGURE 2 ) 1.1 times as long as pleotelson; basis about as long as broad, naked; exopod one-articled, 4.4 times L:W, 0.7 times as long as endopod, with simple medial seta, one stout and one simple setae distally; endopod two-articled, 4.7 times L:W; article-1 with simple and two penicillate distal setae, article-2 with one subdistal seta, one strong, three simple and one penicillate setae distally.
Distribution. This species is known from the continental shelf and slope off southeastern Brazil ( Fig. 3 View FIGURE 3 ), where it occurs at mainly in mud, but also in sand and one station with gravel bottom, at depths ranging from 77 to 1310 m.
Remarks. Hamatipeda prolata sp. nov. is a typical member of the genus Hamatipeda by the presence of conspicuous hook-like spines on the carpus of pereopods 4–6 and with their unguis tip trifurcate. With parallel pereonite margins, the new species is immediately distinguished from H. trapezoida , and the long antennule article-3 distinguishes it from H. sima ( Table 2 View TABLE 2 ). The new species resembles H. longa ( Falkland Islands) in general habitus, how- ever differs by (1) stouter body that is about 15 times L:W ( H. longa is 20 times L:W); (2) cephalothorax slender, 1.7 times L:W (1.3 times L:W in H. longa ); (3) presence of long setae on antennule article-3 (clearly shorter in H. longa ); (4) pereopods 1–3 merus with ventrodistal spine (absent in H. longa ); (5) pereopod-1 carpus with ventrodistal spine (absent in H. longa ); and (6) pereopods 2–3 carpus with two ventrodistal spines (only one in H. longa ).
Finally, Hamatipeda prolata is different from all Hamatipeda species by pereonite-1 more than twice L:W, pereonites 2 and 3 about three times L:W and pereopod-1 merus and carpus with ventral spines.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.