Agathotanaididae (Crustacea: Tanaidacea) from the Angola Basin Author Guerrero-Kommritz, Jürgen text Zootaxa 2003 330 1 15 journal article 51263 10.5281/zenodo.156207 c90a777b-d156-49b0-966b-9bb21c8a4dee 1175­5326 156207 Paragathotanais insolitus n. sp. ( Figs 1 , 2 ) Material : 3 specimens . Holotype ZMH K­ 40345, 1 non­ovigerous female, 1.52 mm , RV Meteor 48, DIVA­1, Station 325, 5450 m, Muc. Paratypes : ZMH K­ 40346, 1 non­ovigerous female, dissected, RV Meteor 48, DIVA­1, Station 325, 5448 m, Muc. ZMH K­ 40347, 1 non­ovigerous female (pleon missing). RV Meteor 48, DIVA­1 station 346, 5388 m, Muc. Description : Non­ovigerous female. Body: ( Fig. 1 a, b) length 1.52 to 1.64 mm , long and slender, cylindrical. 7.5 times as long as broad. Cephalothorax: ( Fig. 1 c) 1.5 times as long as broad, longer than pleon. Pereon: ( Fig. 1 a, b) pereonite 1 as long as pereonite 6. Pereonites 2, 3, 4 and 5 of equal length. Pleon: ( Fig. 1 a, b) pleonite 1 narrower than pereon, pereonites 2 to 5 decreasing in width towards posterior. Pleotelson as wide as pleonite 1, triangular in shape, apex pointed. Antennule: ( Fig. 1 d) composed of four articles. Article 1 longest, longer than the rest of the antennule, with two simple setae. Article 2 with one long, one short, and two thin distal setae. Article 3 as long as broad, with two distal setae. Article 4 with five terminal setae and one aesthetasc. Antenna: ( Fig. 1 e) composed of four articles. Article 1 as long as broad, naked. Article 2 as long as broad, with one distal spine. Article 3 longest, with three dorsal combs of setae, one simple ventral seta, and one aesthetasc. Article 4 very short with four terminal seta, one as long as the antenna. Labrum: ( Fig. 1 f) hood­shaped with long lateral and short central setules. Mandible: ( Fig. 1 g) well developed and well calcified, pars molaris reduced, left mandible with a spiniform lacinia mobilis. Maxillule: ( Fig. 1 h) endite with one short and seven long terminal spines. Maxilla: not recovered. Labium: ( Fig. 1 i) composed of two fused lobes rounded distally, naked. Maxilliped: ( Fig. 1 j) basis oval, endites naked with two distal tubercles. Palp composed of four articles. Article 1 as long as broad without setae. Article 2 with one strong distal seta. Article 3 with three stout inner setae. Article 4 with two terminal and two stout internal setae. Epignath: not recovered. Cheliped: ( Fig. 2 a, b) basis ventrally attached to cephalothorax, as long as wide, naked. Merus triangular with one short ventral seta. Carpus as long as chela with soft ventral protuberance, with seta. Propodus twice as long as broad with one ventral and two short dorsal setae near cutting edge. Cutting edge with four attenuated teeth. Dactylus curved, naked. FIGURE 1. Paragathotanais insolitus n. sp. Holotype ZMH K­40345: a, body, dorsal view; b, body, lateral view; c, cephalothorax, ventral view. Paratype ZMH K­40346: d, antennule; e, antenna; f, labrum; g, mandibles; h, maxillule; i, labium; j, maxilliped; k. uropod. Scale bars: a, b, 1 mm; c, 0.2 mm; all others 0.1 mm. Pereopod 1: ( Fig. 2 c) basis four times longer than broad, without setae. Ischium short, naked. Merus of triangular shape, naked. Carpus with two dorsal spinules and two short terminal setae. Propodus long, with one terminal and one ventral spiniform setae. Dactylus about as long as unguis. Unguis slender, pointed. FIGURE 2. Paragathotanais insolitus n. sp. Paratype ZMH K­40346: a, left cheliped, internal face; b, right cheliped, external face; c, pereopod 1; d, pereopod 2; e, pereopod 3; f, pereopod 4; g, pereopod 5; h, pereopod 6. Scale bar 0.1 mm. Pereopod 2: ( Fig. 2 d) similar to pereopod 1 except ischium with seta, carpus smooth without spinules, merus with one short stout seta and propodus with two ventral spinules. Pereopod 3: ( Fig. 2 e) similar to pereopod 2, exept merus with two short seta and carpus with only one short seta. Pereopod 4: ( Fig. 2 f) basis four times as long as broad, naked. Ischium short, naked. Merus with one long, strong distal seta. Carpus as long as merus with two strong distal setae. Propodus as long as lengths of merus and carpus combined, with three strong terminal setae. Dactylus about as long as unguis. Unguis slender and sharp. Pereopod 5: ( Fig. 2 g) similar to pereopod 4 except merus with two strong setae. Pereopod 6: ( Fig. 2 h): as pereopod 5. Pleopods: absent. Uropods: ( Fig. 1 k) uniramous. Basal article with one distal tubercle. Endopod as long as basal article with two terminal setae. Ovigerous female: unknown. Male: unknown. Type locality : Angola Basin, RV Meteor 48, DIVA , Station 325, 19°58.1´S 002°59.8´E , 5450 m . Etymology : The epithet, insolitus (Latin) for 'uncommon' or 'strange'; alludes to these animals having only four antennal segments and a reduced pars molaris, both uncommon character states for the genus. Remarks : Paragathotanais insolitus can be readily distinguished from all other Paragathotanais species by having only four antennal articles. This species also shows similarities to Agathotanais in the reduction of the pars molaris.