Siphonoecetini Just, 1983 (Crustacea, Amphipoda, Ischyroceridae) 13: Western Australian species of Bubocorophiina in Rhinoecetes, Cephaloecetes, Sinoecetes, Borneoecetes and Pararhinoecetes gen. nov. Just, Jean Zootaxa 2019 2019-02-08 4554 1 101 140 7ZK2X Just, 2019 Just 2019 [151,425,930,956] Malacostraca Ischyroceridae Borneoecetes GBIF Animalia Amphipoda 28 129 Arthropoda species minimus sp. nov.   Figures 19–20   Type fixation. Holotype, ♀, here designated.   Etymology.The epithet indicates that this is a very small and fragile species.   Material.   Holotype, ♀, 3.4 mm. North West Shelf, off Port Hedland, 19°30’S 118°52’E,  39 m, grab, CSIRO RV  Soela,  28 June 1983, stn 03/83/G/B8, WAMC73455.    Paratypes(all: Western Australia, CSIRO, RV  Soela, North West Shelf, between Dampier and Port Hedland). 19°05’S 118°51’E,  82 m, grab,  29 June 1983, stn 03/83/B5,G,R13, WAMC73456 ( 1 specimen). 19°04’S 118° 47’E,  84 m, grab,  29 June 1983, stn 03/83/B6/G, WAMC73457 (1).  19°31’S 118°49’E,  39 m, grab,  28 June 1983, stn 03/83/B7/G, WAMC73458 ( 1♀).  19°30’S 118°52’E,  39 m, grab,  28 June 1983, stn 03/83/G/B8, NHMD 284964( 1♀).  19°05’S 118°47’E,  81 m, grab,  30 June 1983, stn 03/83/B10/G, WAMC73460 ( 1♂). Stn05/83/B7/G, WAMC73461(1).   Description( ♀). Headas long as pereonites 1 and 2 combined along dorsal midline; mid-anterior depression shallow, encompassing approximately 0.3 head length; in dorsal view slender, base of antenna 2 not visible laterally. Rostrumslightly down curved, acutely pointed, in dorsal view reaching beyond apices of eye lobes with about half length. Eye lobesin dorsal view tapering to blunt apex, in lateral view rounded truncate, lower distal margin with 1 simple seta.  Antenna 1approximately as long as head and pereonites 1–4 and half of 5 combined, reaching to apex of article 4 of antenna 2 peduncle; flagellum of 6+ articles, as long as peduncle articles 2–3 and half of 3 combined. Antenna 2approximately as long as head, pereonites, 1–7 and pleonites 1–3 combined; ventral projection of peduncle article 2 approximately one third longer than broad at base, slightly tapering to rounded apex, with short fringe of long simple setae laterally and apically; peduncle articles 4–5 with scattered groups of short simple setae; articles 4 and 5 of equal length; flagellum articles 1 and 2 with 4–5 slender robust setae.  Mouthparts.Mandible palp article 1 with 3 midventral, 2 distoventral and a couple of medial long setae; vestigial article with long seta inserted medioapically.  Gnathopod 1propodus length 3.0 width, with 2 mid-posterior robust setae. Gnathopod 2propodus length 1.6 greatest width, posterior margin straight distal to robust setae. Pereopods 3–4basis with about 5 long setae along middle of anterior margin, merus with anterodistal tuft of a few long setae, posterior margin with scattered unequally long setae. Pereopods 5–6basis anterodistal margin with group of unequally long setae. Sternal papillae not observed.   FIGURE 19.  Borneoecetes minimus  sp. nov.Holotype, ♀. a2flag, antenna 2 flagellum; cdv, cephalon dorsal view; md palp, mandible palp; mx1 plp, maxilla 1 palp; rlv, rostrum right lateral view; us, urosome; vp, antenna 2 article 2 ventral projection. Habitus scale: 1 mm.  Uropod1 peduncle dorsolaterally with 4 robust setae, medial margin with 2 robust setae, with tuft of simple setae distally, ventral apical margin with finely fimbriate corona; outer ramus approximately 0.5 length of peduncle, dorsolaterally with 3 robust setae, with simple setae dorsally; inner ramus 0.7 length of outer ramus, straight, dorsomedially with single robust seta at base of terminal seta. Uropod 2peduncle approximately 0.4 length of peduncle of uropod 1, with 1 or 2 simple setae; ramus about 0.3 length of peduncle, with single robust seta at base of apical robust seta and a few dorsal simple setae, reaching beyond uropod 3 ramus with about 0.5 of its length. Uropod 3ramus with 4–5 unequally long simple setae.  Telsonwidth approximately 1.6 length, apex straight (not illustrated in dorsal view).  Male.The single small male is similar to female except uropods with fewer robust setae.  Size.Only known ♂, 2.4 mm; largest ♀, 3.4 mm; ( 1 ♀of 2.4 mmwith fully developed oostegites).  Colour and biology.No observations.   Distribution. Western Australia, North West Shelf, 39– 84 m.   Remarks.  Borneoecetes minimus sp. nov.differs from the only known congener  B. wongi(in parentheses) as follows: rostrum longer and eyelobes longer and apically truncate (short rostrum and very short, broad and rounded eyelobes); setae on the mandible palp are much longer, and article 2 is at the center of article 1; gnathopod 2 propodus nearly oval, cutting edge almost straight (more elongate, cutting edge concave); uropod 1 peduncle with dorsolateral and mediolateral robust setae (simple setae only dorsally). 2234227508 1983-06-28 CSIRO, RV, WAM Soela 39 -19.5 North West Shelf 1271 118.86667 Port Hedland 28 129 1 1 holotype 2234227597 1983-06-29 CSIRO, RV, WAM 82 -19.066668 North West Shelf 1273 118.78333 Soela 28 129 1 Western Australia paratype 2234227525 1983-06-28 WAM 39 -19.516666 1271 118.816666 28 129 1 1 Western Australia paratype 2234227563 1983-06-28 NHMD 39 -19.5 1271 118.86667 28 129 NHMD 284964 1 1 Western Australia paratype 2234227372 1983-06-30 WAM 81 -19.083334 Stn 1273 118.78333 28 129 1 1 Western Australia paratype