Remarkable Australasian marine diversity: 18 new species in Pentaceration Just, 2009 (Crustacea, Isopoda, Paramunnidae) Just, Jean Zootaxa 2011 2813 1 54 76MCB [151,464,1519,1545] Malacostraca Paramunnidae Pentaceration Animalia Isopoda 6 7 Arthropoda species curvicornis sp. nov.    Typefixation. Holotype, female, here designated.   Etymology.The epithet alludes to the curved lateral head spines.   Material examined.  Holotype,spent Ƥ, 2.35 mm, New Zealand, east coast, 41°04.10'S, 176°22.05'E, 306 m, ring net on trawl warp, 23 February 2000, RV Kaharoa, cruise KAH0001, stn 79, NIWA60500.  Paratypes( 10 specimens ).Same data as holotype, NIWA60501 (3A, 1.82 mm). Same data as holotype, NIWA60502 (2 spent Ƥ). Same data as holotype, NIWA60503 (5 Ƥ, 2 3).   Description(spent females ). Bodytapering towards pleon; width 0.38 length, widest between pereonites 2 and 3. Headlength 0.18 width; length posterior to eyestalks equal to anterior length. Frontal marginmid-spine slender, pointed, length equals combined length of head and half length of pereonites 1; lateral spines equal length of midspine, curved backwards, distally up-curved, diverging at 95°. Eyestalksoverreaching pereonite 1 by about half their length, pointing forward at 10°, slender, pointed, distally up-curved.  Pereonitesall with single slender, upright mid-dorsal spine. Pereonite 1 lateral margins rounded, irregularly denticulate; pereonite 2 and 3 lateral spines diverging at 30°, with slender, up-curved irregularly denticulate spines, length approximately 0.25 pereonite width, margins either side of spine with single anterior denticle, posteriorly with 2 and 1 spines respectively; pereonite 4 with short, pointed lateral spines; 5–7 lateral spines subsimilar to 2 and 3 but narrower; 5 up-curved, with strong denticle on proximoposterior margin; 6 and 7 with proximoanterior lobe, 6 with strong denticle on proximoposterior margin; 5 and 6 with short row of setae on overlapping posterior bulges.  Pleonlength 1.35 width. Pleonite 1width 0.85 distance between uropods, length approximately 0.1 width. Pleotelsonwith distinct neck, proximal and lateral margins forming evenly merging curve, lateral margins convex, with 9–10 denticles, distal projection narrowly triangular at approximately 55°, 0.36 length of entire pleotelson, with rows of lateral simple setae, apex pointed.   FIGURE 4.  Pentaceration curvicornis  sp. nov.Holotype, Ƥ; except F, paratype Ƥ, and M, paratype 3A. a, antenna; au, antennula; cv, head ventral view; up, uropod. Habitus scales: 0.5 mm.   FIGURE 5.  Pentaceration curvicornis  sp. nov.Holotype, Ƥ; except M, paratype 3A. op, operculum (pleopod 2); p1–2, pereopods 1 and 2 (not to scale); pl1–2, pleopods 1 and 2.   Antennulaarticle 1 approximately 0.7 length of 2, wider than 2, tubular; 2 reaching apex of eyestalks, as long as 3–6 combined, 3–4 subequal, 0.6 length of equal 5 and 6.  Antennaarticle 2 about 9 times length of 1, broad with convex lateral margin; article 3 width 0.2 length, with small acute spine distolaterally; article 5 4.4 length of 4; 6 twice length of 5; 6 1.5 length of 5; flagellum articles 1 and 2 slender, 1 approximately 1.2 length of 2.  Pereopod Ibasis length 3.3 width, with row of acute, curved spines anterodistally; ischium 0.75 length of basis, with single acute, curved spine on anterior margin; merus with single acute spine on anterior margin; carpus narrowly oval with nearly parallel anterior and posterior margins; propodus narrowing distally to insertion of dactylus, with 2 robust setae on opposing margin. Pereopod II basis with anterodistal row of acute spines, propodus with single posterodistal robust seta.  Pleopod II(operculum) ovoid with pointed apex, distal margins weakly concave, width 0.66 length, (marginal simple setae not observed).  Uropodsrecessed into simple cuticle fold, protopod and exopod apparently absent; endopod length 5.3 width.  Male.Similar to female, but head spinesand pereonites 1 and 2 lateral spineslonger and more robust than in female, the latter spines lacking strong denticles around base. Pleotelsonposterior projection longer than in female. Pleopod Iproximal lateral sublobe dominant, broadly rounded, completely overlapping smaller, rounded distal sublobe; width 0.27 distance to midline; distal projection length 0.37 pleopod total length, forming narrowly acute angle, with pointed apices. Pleopod IIprotopod rounded distally, lateral margin with simple setae; endopod article 2 (stylet) forming approximately 170° curve.  Size.Largest female (spent), 2.35 mm; largest male, 1.82 mm.   Distribution.Eastern New Zealand,  306 m.