Ianthopsis franklinae Brandt, 1994
Family. Acanthaspidiidae.
Figures. Female Holotype & Paratype (scale 1mm). Female Paratype. Female Paratype. Female Paratype. Female Paratype. Male Paratype (scale 1mm). Male Paratype. Male Paratype.
Synonymy. Ianthopsis franklinae Brandt, 1994: 126.
Type material. Holotype NMV J13269 ♀*, paratypes NMV J13270, J20175–82, J23841*, AM P38893, P42268, P42276*. Type locality: 67 km S of Point Hicks, VIC, 1277 m.
Description.
Body Length in male 6.00–8.00 mm (adult, sex not specified (Brandt, 1994)); female 6.00–8.00 mm (adult, sex not specified (Brandt, 1994)); dorsal surface turberculate. Dorsoventrally flattened, dorsal surface weakly curved; broadly ovate, pereonite 1 near width of pereonite 6–7, other pereonites wider; in male pereonites 2–4 widths subequal, in female pereonites 2–4 subequal.
Head Clypeus projecting medially beneath antennulae, forming rounded arc in dorsal view. Vertex with narrow projecting rostrum overhanging frons. Rostrum projecting dorsally; elongate (length greater than 0.4 width); without serrations; posterior rostral furrow absent. Lateral margin with laterally projecting processes. Eyes distinct and pigmented, with many ocelli; eyelobes absent, eye region sessile on dorsal surface.
Pereonites Pereonite 1–4 tergites projecting laterally, coxae positioned ventrally near lateral margin, 5–7 tergite margins projecting laterally, coxae positioned ventrally near lateral margin. Pereonite lateral margins 1 angular and projecting; 2–3 lateral margins angular and projecting; 4 lateral margins angular, 5 lateral margins angular, 6–7 lateral margins angular and projecting. Lateral margins finely denticulate, finely denticulate. Lateral margin 1 with pair of spines, margin 2 with pair of spines, margin 3 with pair of spines, margin 4 with pair of spines; margin 5 with pair of spines, margin 6 with pair of spines, margin 7 with pair of spines. 1–4 dorsal surface with single spines on midline and with spines in transverse row, 1 with multiple spines, 2 with multiple spines, 3 with multiple spines, 4 with multiple spines; 5–7 dorsal surface with spines on midline, 5 with single spine, 6 with single spine, 7 with single spine.
Pleon Length near width; in lateral view approximately in line with respect to pereonal body axis. Pleonite 1 fused to pleotelson but freely articulated to pereonite 7. Pleotelson dorsal surface smoothly convex, cuticle smooth; laterally rounded; lateral margins denticulate only level with uropods; posterior margin set apart from lateral margins by concavity at level of uropods, weakly produced, forming rounded angle posteriorly, smooth. Uropods inserting on margin of pleotelson, at posterior margin but separated by anus and distal apex of pleotelson; sockets for insertion large and distinct (obvious when uropods broken off). Anus positioned posteroventrally on pleotelson, posterior to pleopodal chamber; exposed, uropods positioned lateral to anus.
Antennula Short, with 7–8 articles or with 9 to 13 articles (8 in female, 9 in male). Article 1 shorter than 2; tubular, width only slightly broader than article 2. Article 2 length 1–3 times article 1 length. Article 4 shorter than articles 3 and 5, articular margins parallel to each other.
Antenna Article 3 with well-articulated large scale longer than article 4; somewhat enlarged, near length of basal articles 1–2 together. Article 4 approximately tubular, length approximating width. Article 5 distinctly longer than article 4; approximately tubular. Flagellum article 1 elongate in both sexes, tubular; with 17 articles.
Mouthparts. Mandible palp not reaching incisor process, article 2 tubular, article 3 straight, with few spinulate setae; incisor process with well-defined cusps (4–5); molar process elongate, curved and narrow, distal triturative surface substantially reduced. Maxilla medial pectinate setae present. Maxilliped palp narrower than basis endite, article 2 wider than article 3; endite with 3 coupling hook(s).
Pereopods Dactyli II-VII with two terminal claws, dorsal claw much larger than ventral claw, ventral claw robust. Pereopod I not prehensile, ambulatory, similar to posterior legs, no obvious palm, dactylus short, propodus and carpus longer and not broadened; basis similar length basis pereopod II, basis same length basis of pereopods III and IV, basis in males longer than propodus, basis anterior margin smooth; carpus width subequal throughout, carpus long and thin, near length of basis and ischium, carpus lacking palm, straight ventral margin, carpus pectinate setae absent on palm; dactylus of male proximal ventral margin smoothly concave. Pereopods II-VII distolateral margin of carpus smooth. Pereopods III-IV basis elongate, length much greater than width. Pereopods V-VII basis lengths similar. Pereopod V basis similar length basis pereopod IV.
Pleopods Pleopod I of males length much greater than twice proximal width; midline nearly completely fused, with only distal incision separating both sides; distal tip truncated; distal tip lateral lobe not projecting beyond more proximal lateral margin; lateral margins relatively straight; lateral margins simple setae present; hemiplumose setae on ventral surface absent. Pleopod II of females midline smoothly convex; in ventral view triangle shaped, distolateral margins concave; distal margin convex, distal tip of operculum extending beyond distal margin of lateral fields; plumose setae on margin present. Pleopod II of males protopod apex narrow, tapering; setae on lateral and distal margin, simple; appendix masculina longer and narrower than endopod proximal article; appendix masculina stylet extending beyond tip of protopod; appendix masculina stylet distal tip tapering to a point. Pleopod III exopod extending beyond tip of endopod, distally broad and rounded, without articulation between articles 1 and 2, fringe of fine setae present, simple setae absent, article 2 with row of plumose setae; endopod with 4 or more plumose setae (6). Pleopod IV exopod present; shorter than endopod; lacking plumose setae. Pleopod V present; endopod divided into 2 articles.
Uropods Elongate, exceeding half pleotelson length. Protopod tubular, length greater than width; longer than longest ramus. Biramous, exopod long.
Distribution. 200 mile fishing zone (SE oceanic), VIC.
Ecology. Benthic, continental slope, marine, soft bottom-marine.
Cite this publication as: ‘G.D.F. Wilson, R.T. Johnson & S.J. Keable. 2004 onwards. ‘Isopoda: Species of Asellota.' http://crustacea.net’.
