Neastacilla Tattersall, 1921 redefined, with eight new species from Australia (Crustacea: Isopoda: Arcturidae) King, R. A. Memoirs of Museum Victoria 2003 2003-12-31 60 2 371 416 45YF6 King 2003 [131,389,1753,1775] Malacostraca Arcturidae Neastacilla Animalia Isopoda 5 376 Arthropoda species coonabooloo sp. nov.   Figures 1–3  Material examined.  Holotype. Australia: Vic., Crib Point, Western Port, 38º21.15'S, 145º13.36'E,  9 m,  24 Mar 1965, NMV J1036( 1 female, 6.6 mm).   Paratypes. Australia: NSW. Moes Rock, S of Jervis Bay, AM P32681( 1 female), AM P32680( 1 female). Vic.Crib Point, Western Port, 38º21.63'S, 145º15.08'E,  9 m,  23 Feb 1965, NMV J978( 1 female), NMV J979( 1 female). Western Port, 38º22.0'S, 145º32.0'E, NMV J980( 1 immaturefemale, 1 immaturemale). Mallacoota, 37º34.03'S, 149º46.02'E,  5 m,  6 Apr 1989, NMV J47324( 1 immaturefemale).  Tas.Breaksea Island, Bathurst Harbour,  4 m,  16 Feb 1989, NMV J47323( 1 male, 5.5 mm).  Description of female.Head with small dorsal elevation posteriorly, anterolateral lobes angular, small rostral point present; lateral margin of head and pereonite 1 incised. Pereonite 1 extended anterolaterally. Pereonites 2 and 3 without dorsal elevations, progressively wider, with small lateral extensions. Pereonite 4 about 8 times as long as pereonite 3, wider than previous pereonites, widest at midlength; with 2 anterior horn-like dorsal elevations, lateral margins extended and curved dorsally at midlength. Pereonites 5–7 progressively shorter posteriorly; without dorsal elevations. Pleon length greater than combined lengths of pereonites 5–7, without dorsal elevations, with small anterior lateral wings, apex rounded. Eyes small and oval. Antenna 1 reaching to third peduncular article of antenna 2; aesthetascs present distally and laterally on flagellum. Antenna 2 slender, more than half as long as body; flagellum of 2 articles ending with claw, row of scales along full length. Maxilla 1 mesial lobe with 3 plumose terminal setae; lateral lobe with 9 distal robust setae. Maxilla 2 mesial lobe with 22 plumose setae; middle lobe with 3 setae; lateral lobe with 3 setae. Maxillipedal endite with 13 mesial setae, 1 coupling hook; palp article 2 with mesial setal rows; articles 3 and 4 with mesial and lateral setal rows; article 5 with mesial and distal setae. Pereopod 1 propodus as long as carpus; dactylus twice as long as wide, without unguis. Pereopods 2–3 dactylus present. Pereopod 4 dactylus absent. Pereopods 5–7 dactylus somewhat denticulate, with unguis and secondary unguis; secondary unguis half-length of primary unguis. Uropodal exopod with 2 setae of subequal length. Oostegite 4 with suture at midlength. 5.0– 6.6 mm.  Male.Head with a small dorsal elevation posteriorly, anterolateral lobes angular, small rostral point present; lateral margin of head and pereonite 1 incised. Pereonite 1 extended anterolaterally. Pereonites 2 and 3 of similar width; without dorsal elevations, small lateral extensions present. Pereonite 4 about nine times as long as pereonite 3, constricted for first third of length; with 2 anterior horn-like dorsal elevations, anterolateral margins not extended. Pereonites 5–7 progressively shorter posteriorly; without dorsal elevations. Pleon length greater than combined lengths of pereonites 5–7; without dorsal elevations, with small anterior lateral wings, apex rounded. Antenna 1 reaching half way along third peduncular article of antenna 2; aesthetascs present distally and laterally on flagellum. Antenna 2 slender, more than half as long as body; flagellum of 3 articles ending with a claw, a row of scales full length. Mouthparts, pereopods and uropods as for female. Pleopod 1 exopod with a lateral notch and 2 plumose lateral setae of unequal length. Pleopod 2 appendix masculina with ridge on posterior face, curved, extending third length past the endopod, apex simple. Penial plate widened proximally, distally tapered, apex simple.  Figure 1.  Neastacilla coonabooloo sp. nov., male (NMV J47323): A, dorsal view; B, lateral view. Female holotype (NMV J1036): C, dorsal view; D, lateral view. Scale = 1.0 mm.  Figure 2.  Neastacilla coonabooloo sp. nov., female holotype (NMV J1036): MX1, left MX2, left MD, left MXP, A1, A2, antenna 2. Male (NMV J47323): A1, A2. Scales: a (MXP, MX1, MX2, MD) = 0.2 mm; b (A1, A2) = 0.5 mm.  Figure 3.  Neastacilla coonabooloo sp. nov., female holotype (NMV J1036): P1, P3, P4, P5, U; A, ventral view. Male (NMV J47323): Pe, PL1, PL2. Scales: a (P1, P3, P4) = 0.5 mm; b = (A) 1.0 mm; c (P5) = 0.5 mm; d (U, Pe, PL1, PL2) = 0.2 mm  4.5–5.6 mm  Distribution. Australia: New South Wales, Victoria, Tasmania; subtidal to 9 mdepth.  Etymology. “Coonabooloo” is an Aboriginal word meaning two shoulders and refers to the extended lateral margins of pereonite 4 inthe female of this species.  Remarks.This species possesses an incised dorsolateral groove at the fusion of the head and pereonite 1 as does  Neastacilla deductaand  N. monoseta. Females of  N. coonaboolooare distinguished from these two species by the presence of extended lateral margins on pereonite 4 and two anterior horn-like elevations on pereonite 4. Males of  N. coonabooloopossess smaller horn-like elevations.  N. coonabooloocan be further differentiated from  N. monosetaby possessing a pleon with small rounded lateral wings, as opposed to the large acute wings in  N. monoseta.In the material examined here, the heights of the dorsal elevations on pereonite 4 vary from small bumps to spine like elevations. 1965-03-24 NMV Australia 9 -38.3525 Crib Point 11 145.22267 Western Port 5 376 J1036 1 1 holotype 1965-02-23 1989-04-06 1965-02-23 AM, NMV Australia Bathurst Harbour 9 -37.567165 Moes Rock 11 149.767 Tas. Breaksea Island 5 376 P32681, P32680, J978, J979, J980, J47324, J47323 8 4 3 1 paratype