Kudinopasternakia serejae, Santos, Kátia Christol Dos, 2014

Santos, Kátia Christol Dos, 2014, Two new species of Kudinopasternakia Guţu, 1980 (Crustacea: Tanaidacea: Sphyrapodidae) with remarks on setology nomenclature, Zootaxa 3826 (3), pp. 563-578 : 571-575

Kudinopasternakia serejae n.sp.

Figs. 5–6

Material examined. All from the continental slope off the Atlantic coast of south-eastern Brazil, Campos Basin; twelve specimens.

Holotype: MZUSP 31464, (one female with oostegites), 705 m, Stn. HAB4 CANG 7 R2. Paratypes: MZUSP 31465, (one female without oostegites – pieces illustrated), 790 m, Stn. HAB 07 I07 R2; MZUSP 31466, (one female without oostegites – body illustrated), 792 m, Stn. HAB 07 I07 R3; MZUSP 31467, (one female without oostegites), 709 m, Stn. HAB04 CANG 7 R2; MZUSP 31468, (two females without oostegites), 720 m, Stn. HAB09 CANG 7 R1; MZUSP 31469, (one juvenile; three mancae), 720 m, Stn. HAB09 CANAC 7 R1; MZUSP 31470, (one juvenile), 758 m, Stn. HAB6 CANAC 7 R1.

Diagnosis. Rostrum pointed; antennule outer flagellum with three articles; antenna with nine articles; mandible palp article 2 with two serrate setae, setiferous lobe with three bifurcate and two simple setae; maxillule palp with three distal setae; pereopod 1 carpus with two large and one short spiniform setae, shortest (proximal) with tip reaching the insertion of next seta, propodus with three large and one short spiniform setae; pereopod 4 propodus with one ventral spiniform seta; pereopods 5 and 6 unguis ventral margin with acute denticles; pleonite epimera rounded.

Description of female. Body ( Fig. 5 A–B) 3.8 mm long, semi-cylindrical, dorsoventrally flattened, 5.8 times as long as the width of cephalothorax. Rostrum pointed. Ocular lobes present, without ommatidia or pigmented elements. Cephalothorax without setae, as long as wide, about 0.22 times total body length.

Pereon about 2.4 times as long as cephalothorax length; six free pereonites, sixth shortest, pereonites 4 and 5 longest.

Pleon about 0.2 times total body length. Pleonites all wider than long, with rounded epimera and pleopods. Pleotelson longer than wide.

Antennule ( Fig. 5 C) article 1 four times as long as broad, with four simple setae on outer margin, three simple setae on inner margin; article 2 1.4 times as long as broad with one simple seta on inner margin, two simple setae on outer margin; article 3 broader than long with setae on each margin distally; article 4 without seta; inner flagellum last article bearing three setae terminally; outer flagellum three–articled, second article with one aesthetasc, last article with one aesthetasc and three setae terminally.

Antenna ( Fig. 5 D) composed of nine articles; first article tumid, with part of surface ridged. Second article slender and twice as long as first, pseudosquama with one long simple seta; third article short and naked; fourth article thinner and longer than second, with two broom setae on both inner and outer margins. Following articles thinner, decreasing in length to last article. All articles with simple setae, last one with four terminal setae.

Mandible ( Fig. 5 E, E1–3) molar and incisor with irregular cutting edge ( Fig. 5 E.3), palp tri-articulate, article 2 with two serrate setae subterminal and article 3 with row of minute and finely serrate setae, two serrate setae terminally ( Fig. 5 E.1); right mandible ( Fig.5 E.2) setiferous lobe with three bifurcate and two simple setae, left mandible ( Fig.5 E) lacinia mobilis with four prominent teeth.

Maxillule ( Fig. 5 F) outer endite with eleven terminal setae; inner endite with four pinnate setae; with setules on outer margin of both endites; palp having distal article armed with one terminal and two subterminal simple setae.

Maxilla ( Fig.5 G) fixed endite inner lobe armed with a row of twenty–one curved simple setae guarding two long spiniform setae; outer lobe with one simple, one distally bifid and one proximally setulose setae; movable endite inner lobe with five long simple setae. Both margins setulate distally.

Maxilliped ( Fig. 5 H) coxa narrow, basis outer margin with six setulated spiniform setae ( Fig. 5 H.1); endite with two couplers, eleven circumplumose setae on inner margin, three truncate and four simple setae terminally ( Fig. 5 H.2); palp four–articled, article 1 as long as broad with one simple seta on outer margin; article 2 with one seta on outer and nine–ten setae on inner margin; articles 3 and 4 each with seven simple setae on inner margin (not all setae illustrated).

Epignath ( Fig. 5 I) body naked and terminal seta with setules.

Cheliped ( Fig. 6 A) basis with two short setae ventrally, exopod three-articled with five long terminal plumose setae; merus with one distoventral simple seta; carpus longer than merus with four ventral simple setae; fixed finger of propodus with three ventral and three dorsal simple setae on lateral surface; articulation of the dactylus with two simple seta on lateral surface; dactylus with a cluster of three simple setae on mesial surface. Teeth on grasping and/or cutting edges of fixed finger and dactylus as figured.

Pereopod 1 ( Fig. 6 B) basis almost 1.7 times as long as merus and as long as carpus and propodus combined, with two minute simple setae on ventral surface; ischium with one distoventral seta; carpus as long as merus, with three spiniform setae, the smallest one reaching the insertion of adjacent one, one simple seta on ventral surface, one spiniform and one simple setae on lateral surface, row of four simple setae on dorsolateral surface; propodus with four spiniform setae on ventral surface, proximal one smaller; dorsal surface with two simple and two spiniform setae distomesially. Dactylus smaller than propodus, with two spines on ventral margin.

Pereopod 2 ( Fig. 6 C, C.1) basis 0.9 times as long as merus, carpus and propodus combined, with two minute simple setae on ventral surface and one minute simple seta on ventral surface, medially; ischium with one ventral seta; merus with two distoventral, one subterminal and one distodorsal simple setae; carpus with five simple setae on ventral surface, one simple subterminal and two simple setae on distal half of dorsal surface; propodus ( Fig. 6 C.1) with five simple setae on ventral surface, one simple seta sub-terminally, three simple setae on dorsal surface and one simple seta on mesial surface; dactylus and propodus of equal length, with single seta on distal half; unguis with small spine.

Pereopod 3 ( Fig.6 D, D.1) similar to pereopod 2 but basis 1.13 times as long as merus, carpus and propodus combined; merus with one simple seta sub-terminally and one simple seta distally on ventral surface; carpus with six simple setae on ventral surface and two simple setae distolaterally; propodus ( Fig. 6 D.1) with three simple setae on ventral surface, two simple setae on dorsal surface; dactylus and unguis combined 1.2 times as long as propodus, with one small ventrodistal seta near unguis; unguis with two small spiniform projections on ventral margin.

Pereopod 4 ( Fig. 6 E, E.1) basis about as long as merus, carpus and propodus combined, without seta; ischium naked; merus with one distoventral seta; carpus longer than merus or propodus, with one spiniform seta on ventral surface and three spiniform setae sub-terminally on dorsal surface; propodus ( Fig. 6 E.1) with one broom seta mid–dorsally, one spiniform seta on ventral surface and crown of finely denticulate setae terminally; dactylus and unguis combined as long as propodus, with one small mid-ventral seta; unguis with small spiniform projection on ventral margin.

Pereopod 5 ( Fig. 6 G, G.1) basis about 1.2 times as long as merus, carpus and propodus combined, with one tiny simple seta distally on ventral margin; ischium and merus as pereopod 5; merus and carpus subequal in length, merus with two and carpus with four simple setae distally on ventral margin; propodus with four simple setae on distal half of ventral margin, one simple seta sub-terminally, one simple and two half serrate setae distally on dorsal margin; dactylus and unguis combined 1.15 times as long as propodus, with one ventrodistal seta; unguis ventral margin smooth.

Pereopod 6 ( Fig. 6 F, F.1–2) basis as long as merus, carpus and propodus combined, with small simple seta distoventrally; ischium as in pereopod 3; merus and carpus subequal in length, each with one simple seta on ventral margin; propodus with four serrate setae on lateral margin, row of three serrate setae and one long simple seta on dorsal surface terminally, one broom seta on dorsal surface in distal half and three long simple setae distally on ventral surface; dactylus and unguis combined as long as propodus with one ventrodistal seta on dactylus; unguis with two minute spiniform projections on ventral margin.

Pleopod ( Fig. 6 H) basal article naked; endopod with one plumose seta medially, five unequal long distal plumose setae; exopod biarticulate, article 1 with one plumose seta and article 2 with seven unequal distal plumose setae.

Uropod ( Fig. 6 I) basis 2.75 times as long as wide, naked; exopod with four articles, two long simple setae distally; endopod composed of ten articles.

Sexual dimorphism. Female with oostegites on cheliped and pereopods 1 to 4. Male not known.

Other stages. Manca with 6–articled exopods found on pereopods 4 ( Fig. 6 J) and 5 ( Fig. 6 K), first article as long as the following combined.

Etymology. The new species in named in honour of Cristiana Serejo, whose research is dedicated to amphipod taxonomy. She has always encouraged the author to pursue taxonomic studies of tanaidaceans.

Type-locality. Campos Basin, 21º56.12'S – 39º57.86'W, 705 m.

Geographic d istribution. Slope of the Atlantic coast off south-eastern Brazil, Campos Basin, 705–792 m depth.

Remarks. Kudinopasternakia serejae n.sp. differs from all species in that (i) the pereopod 4 propodus has one spiniform seta on ventral surface and (ii) the basal article of pleopods is naked, without plumose seta. A pointed rostrum is present on K. serejae and almost all species known (except K. amazonica ), and other characters are shared with some other species: (i) the outer margin of antennule article 1 with three setae and (ii) the epimera on the pleonites rounded (except K. dispar , K. larisae and K. trispinosa ). Besides these similarities, K. serejae differs from K. trispinosa in: (i) the antennule outer flagellum with three articles (instead of four); (ii) nine articles on antennule (versus ten); (iii) propodus of pereopod 4 with one spiniform setae on ventral margin (instead of four) and (iv) the unguis of pereopod 6 smooth, instead of with acute denticles on ventral margin; it differs from K. siegi in: (i) the maxillule palp with three distal setae (instead of six), (ii) the number of spiniform setae on the ventral surface of the carpus and propodus of pereopod 1 (three and four, respectively instead of two and five); (iii) propodus of pereopod 4 with one spiniform setae on ventral margin (instead of four); (iv) unguis of pereopod 5 with ventral margin serrate (instead of smooth).

Kudinopasternakia serejae differs from K. falconae and K. balanorostrata by combination of these characters: (i) three distal setae on maxilliped palp (instead of five and four, respectively); (ii) pereopod 4 propodus with one spiniform seta on ventral surface (versus three); K. serejae also differs from K. falconae in having: (i) nine articles on antenna instead of ten and (ii) propodus of pereopod 4 with one spiniform setae on ventral margin (instead of three) and (iii) the unguis of pereopod 6 smooth, instead of serrate; K. serejae also differs from K. balanorostrata in having: (i) outer flagellum of antennules with three articles (versus four) and (ii) the number of spiniform setae on the carpus and propodus of pereopod 1 is the same, but the positions and sizes of these setae are distinct.

Kudinopasternakia serejae differs from K. bispinosa and K. brasiliensis in that the combination of these characters: (i) three articles on outer flagellum of antennules instead of four and (ii) propodus of pereopod 4 with one spiniform setae on ventral margin (instead of three). The new species also differs in having (iii) three and four spiniform setae on carpus and propodus of pereopod 1, respectively while K. bispinosa has two on each article and K. brasiliensis two on carpus and three on propodus.

Kudinopasternakia serejae differs from K. dispar in having (i) the number of spiniform setae on the ventral surface of the carpus and propodus of pereopod 1 (three and four, respectively instead of four and five); (ii) pereopod 4 propodus with one spiniform seta on ventral surface (versus five) and (iii) epimera on pleonites rounded (versus pointed).

These comparisons are summarised in the key given below.

Figures

FIGURE 5. Kudinopasternakia serejae n. sp. Female without oostegites, paratype, MZUSP 31466 (3.8 mm): A dorsal view; B lateral view. Female without oostegites, paratype, MZUSP 31465: C antennule; D antenna; E right mandible, E. 1 palp distal article, detail, (E. 2) left mandible, incisive, detail, E. 3 molar, detail; F maxillule, F. 1 palp, distal article; G maxilla; H maxilliped, H. 1 outer margin of basis, detail of setulated spiniform setae, H. 2 endite, detail; I epignath.

FIGURE 6. Kudinopasternakia serejae n. sp. Female without oostegites, paratype, MZUSP 31465 (3.8 mm): A cheliped; B pereopod 1; C pereopod 2, C. 1 propodus – dactylus detail; D pereopod 3, D. 1 propodus – dactylus detail; E pereopod 4, E. 1 propodus – dactylus detail; F pereopod 5, F. 1 propodus – dactylus detail, lateral view; F. 2 propodus – dactylus detail, mesial view; G pereopod 6, G. 1 propodus – dactylus detail; H pleopod; I uropod. Manca: J pereopod 4; K pereopod 5.