A new tanaidacean subfamily, Bathytanaidinae (Crustacea: Paratanaididae), from the Australian continental shelf and slope Author Larsen, Kim Author Heard, Richard W. text Zootaxa 2001 2001-12-20 19 1 22 journal article http://doi.org/10.5281/zenodo.4618295 52ae2ec9-fbda-4d82-bf74-ab4257c79648 1175­5326 4618295 B9B4322E-4550-46A7-A34B-3A8392156A7C Bathytanais arenamans n. sp. ( Figs. 3 & 4 ) Material examined : Holotype : Non­ovigerous female, P 61357 , body length 3.1 mm , Sta. SO 5­83 ­B2, 19º56,7’S . 117 º53,6’E . Depth 41 m . Paratypes : 2 Non­ovigerous females, P 61358 , same locality. Collected by staff on board RV “Soela” CSIRO 1983 . Other material : 24 Non­ovigerous female , P 52206 , same locality . 2 females , P 52191 , Sta. No. SO 2­83 ­B 12 , Lat. 19 º 56.9 'S , Long. 117 º 53.7 ' E . Depth 43 m . 9 females , P 52349 , Sta. No. SO 4­83 ­B 1 , Lat. 19 º 58.9 'S , Long. 117 º 51.7 'E . Depth 42 m . 1 female , P 52351 , Sta. No. SO 4­83 ­B 7 , Lat. 19 º 30.8 'S , Long. 118 º 49.4 ' E . Depth 38 m . 3 females , P 52195 , Sta. No. SO 3­83 ­B 2 , Lat. 19 º 56.4 'S , Long. 117 º 53.9 ' E . Depth 44 m . 1 female , P 52204 , Sta. No. SO 4­83 ­B 17 , Lat. 20 º00.2'S , Long. 117 º00.5'E . Depth 52 m . 1 female , P 52199 , Sta. No. SO 4­83 ­B 2 , Lat. 19 º 56.7 'S , Long. 117 º 53.8 ' E . Depth 42 m . 1 female , P 52200 , Sta. No. SO 4­83 ­B 10 , Lat. 19 º05.0'S , Long. 118 º 57.9 'E . Depth 86 m . 1 female , P04971 , Sta. No. SO 2­83 ­B 3 , Lat. 19 º 55.9 'S , Long. 117 º 56.8 'E . Depth 42 m . 4 females , P 52191 , SO 2­ 83 ­B 12 , Lat. 19 º 56.9 ' , Long. 117 º 53.7 'E . Depth 43m . 1 juvenile , P 52208 , Sta. No. SO 5­ 83 ­B 5 , Lat. 19 º04.8'S , Long. 118 º 50.7 'E . Depth 81 m . Diagnosis : Antennal 2 article 2 as deep as long, with disto­ventral quadrate process extending just past articulation of article 3 and 4 ; article 3 inserted dorsally into article 2 , rounded disto­dorsally and armed with blunt, subapical tooth. Labium without antero­lateral projections. Uropod exopod about half as long as endopod. Description (adult female). Body ( Fig. 3 A): Slender, sub­cylindrical, approximately 8 times longer than broad. Cephalothorax ( Fig. 3 B): Shorter than length of pereonites 1 and 2 together, width 0.75 length, antero­lateral corners curving anteriorly. Eye lobes smoothly curved. Pereonites : Pereonite 1 wider than long, extending over cephalothorax at pereopod attachment. Pereonites 2, 3 and 5 , longer than wide. Pereonites 4 and 6 length subequal width. Pleon : Pleonites 1­5 subequal, width approximately 4.0 length. Pleotelson as long as 2 last pleonites together. Antennule ( Fig. 3 C): Shorter than cephalothorax. Article 1 greatly swollen, only marginally longer than wide, longer than combined length of rest of antennule (excluding setae), with several sensory setae on inner margin and 2 short simple distal setae. Article 2 more than half as long as article 1 , distal margin with 2 long simple setae and 2 short sensory setae. Article 3 one quarter as long as article 2 , with 1 long setulated and 1 simple distal setae. Article 4 half as long as article 2 , with 5 distal serrated setae twice as long as antennule. Antenna ( Fig. 3 D): as long as combined length of 3 first articles of antennule. Article 1 smooth, as long as article 3 . Article 2 with 1 distal dorsal simple seta, ventral process extending beyond article 3 with on distal simple ventral seta. Article 3 quadrate with short dorsal spiniform seta. Article 4 longer than article 5 , armed distally with 1 long serrate seta, 1 short simple seta and 3 sensory setae. Article 5 half as long as article 4 , with 2 long setulated distal setae. Article 6 minute, with 2 setulose setae longer than antenna itself, 2 long­ and 1 short simple setae. FIGURE 3. Bathytanais . arenamans , female A holotype, B­L dissected paratype. A) Dorsal view. B) Cephalothorax. C) Antennule. D) Antenna. E) Labrum. F) Left mandible. G) Right mandible. H) Maxillule. I) Maxilla. J) Labium K) Maxilliped. L) Cheliped. Mouthparts : Labrum ( Fig. 3 E) setose, with rounded apex. Mandibles ( Figs. 3 F & G) molar longer than incisor, left mandible with strongly defined lacina mobilis with several denticulations, incisor unidentate, right mandible with broad and bidentate incisor. Maxillule ( Fig. 3 H) with 7 thick terminal setae and row of setae, palp not recovered. Maxilla ( Fig. 3 I) triangular. Labium ( Fig. 3 J) tapering distal and with numerous distal setulated scales. Maxilliped ( Fig. 3 K) endites with 1 simple seta on inner corner and 2 flat distal setae; palp article 1 , outer margin longer than inner, smooth; article 2 , inner margin longer than outer, with 3 setulated setae on inner margin; article 3 , with 4 setulated setae on inner margin; article 4 , rectangular, inner margin with 4 setulated distal setae, outer margin with 1 setulated seta. Epignath not recovered. Cheliped ( Fig. 3 L): Basis twice as long as wide with 1 minute simple distal seta,. Merus ovoid, with 1 simple seta medially on ventral margin. Carpus oval, marginally longer than basis, with 2 simple setae on ventral margin, 2 setae on dorsal margin. Propodus slender, with 2 distal dorsal setae at dactylus insertion and 1 simple seta medially at dactylus insertion. Fixed finger with strong bifurcated apex, 2 simple setae on ventral margin, 3 on cutting edge. Dactylus narrow, with 1 seta on its dorsal surface. Oostegites : originating from pereonites 1­4 . Pereopod 1 ( Fig. 4 A): Longer than other pereopods. Coxa with 1 simple seta. Basis as long as 3 succeeding articles combined, with 1 proximal simple setae on ventral margin. Ischium with 2 simple setae on dorsal margin. Merus longer than carpus, with 1 simple distal seta on dorsal margin. Carpus two thirds as long as propodus, with 2 short simple distal setae. Propodus as long as merus, tapering distally, with 2 short and 1 long simple distal setae. Dactyl and terminal seta together longer than propodus. Pereopod 2 ( Fig. 4 B): Similar to pereopod 1 , except: Merus smooth and as long as carpus. and propodus as long as dactylus and terminal setae combined. Pereopod 3 ( Fig. 4 C): Similar to pereopod 2 , except: Ischium smooth, merus with 1 simple seta, carpus smooth, dactyl and terminal seta together longer than propodus. Pereopod 4 ( Fig. 4 D): Basis stout with 1 simple and 1 sensory distal setae. Ischium with 2 simple ventral setae. Merus ovoid, longer than carpus, with 1 simple, 1 short stout denticulated seta, and denticulated scales. Carpus shorter than propodus, with denticulated scales, 1 simple setae and 4 short stout denticulated distal setae. Propodus with 1 dorsal sensory, 1 long serrated, 1 spiniform, and 1 spiniform setulose distal setae. Dactyl and terminal spine fused into claw with setules. Pereopod 5 ( Fig. 4 E): As pereopod 4 , except: Basis with 1 simple dorsal seta. Carpus with 3 spiniform denticulated distal setae. Pereopod 6 ( Fig. 4 F): As pereopod 4 except: Basis smooth, ischium with 1 simple seta, merus with denticulated scales and 1 short denticulated setae, carpus with 4 short denticulated distal setae, propodus without sensory seta but with 2 spiniform subdistal and 3 stout setulated distal setae as long as dactylus. Pleopods ( Fig. 4 G): All 5 pairs similar. Protopod trapezoidal. Exopod armed with 19 plumose setae. Endopod, inner margin finely setose, with 14 plumose setae, 2 distal setae shorter and stouter than rest. Uropods ( Fig. 4 H): Protopod elongated, smooth. Endopod articulation weak, with 1 simple and 2 sensory setae at midlength on second article element and 4 long­ 1 short simple­ and 1 sensory distal setae. Exopod with 3 short­ and 1 long simple setae. FIGURE 4. Bathytanais arenamans , female paratype. A) Pereopod 1. B) Pereopod 2. C) Pereopod 3. D) Pereopod 4. E) Pereopod 5. F) Pereopod 6. G) Pleopod. H) Uropod. Male: unknown Etymology: Named after the preferred habitat of most Bathytanais species (Latin: arena­mans = sand­lover). Habitat : Specimens living in sandy bottom at 41 m depth on the Northwest Australian shelf off Western Australia . Specimens were found in tubes consisting of sand grains and mucus. Remarks: Bathytanais arenamans is distinguished from the other known members of the genus by the shape of antennal article 1 with is swollen and only marginally longer than wide. B. arenamans superficially resembles B. juergeni . Article 3 of antenna 2 in B. arenamans , however, has a subapical blunt, tooth­like seta instead of the acute disto­dorsal process that characterizes B. juergeni . Also ventral process of antenna article 2 does not extend beyond article 3 in B. juergeni .