Tanaissus bamberi Esquete

Esquete, Patricia, Rubal, Marcos, Veiga, Puri & Troncoso, Jesus, 2015, A new species of heterochelous tanaidacean Tanaissus (Paratanaoidea: Tanaissuidae) from the north-west Iberian Peninsula, Zootaxa 3995 (1), pp. 189-202 : 191-195

publication ID	https://doi.org/ 10.11646/zootaxa.3995.1.17
publication LSID	lsid:zoobank.org:pub:37772558-6DAC-451B-9E60-2D60818791BD
DOI	https://doi.org/10.5281/zenodo.6108488
persistent identifier	https://treatment.plazi.org/id/03B08797-FFE2-FF98-FF75-FF40FCA4FE94
treatment provided by	Plazi
scientific name	Tanaissus bamberi Esquete
status	sp. nov.

Treatment

Tanaissus bamberi Esquete View in CoL , sp. nov.

( FigS 2‒7 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 )

Material examined. Holotype - female ( MNCN 20.04/10129), Gelfa, 41º46'24" N; 8º52'30" W, 10–15 m, 25 May 2012, collected by P. Veiga & M. Rubal.

Allotype —male ( MNCN 20.04/10130), Gelfa, 41º46'24" N; 8º52'30" W, 10–15 m, 25 May 2012, collected by P. Veiga & M. Rubal.

Paratypes —one female ( MNCN 20.04/10131, MNCN 20.04/10132), dissected; one male ( MNCN 20.04/ 10133, MNCN 20.04/10134), dissected; one neuter ( MNCN 20.04/10135, MNCN 20.04/10136), dissected; one male ( MNCN 20.04/10137), two neuters, ( MNCN 20.04/10138, MNCN 20.04/10139), Gelfa, 41º46'24" N; 8º52'30" W, 10–15 m, 25 May 2012, all collected by P. Veiga & M. Rubal.

Other material —one neuter, from Foz, (43º 33'37" N; 7º15'25" W); 52 neuters from, Barqueiro, (43º44' 9"N; 7º42'6"W). All coll. P. Veiga & M. Rubal.

Etymology. Named after Roger N. Bamber, beloved friend and great master, who greatly contributes to our knowledge of tanaidaceans worldwide.

Diagnosis. Female/neuter. Cephalothorax without two parallel dorsal crenulate ridges. Pleonites 1–5 altogether about as long as pereonites 5–6 and half of 4. Mandibular molar process acuminate with sharp tip. Cheliped propodus with dorsal crest and inner row of simple spines. Chela fixed finger well separated from rest of the chela by ventral invagination, forming neck; fixed finger with one semicircular tooth and entire claw. Pereopods 2–3 sternal carpal spine straight. Uropod exopod with two segments. Male. Cephalothorax as long as pereonites 1–3 combined. Pereonites 2–5 each about as long as broad, not enlarged. Pleonites 1–5 as long as pereonites 4–6 and half of 3, pleonites 3–5 about as long as broad or longer. Antennule peduncle of two articles, flagellum of four segments. Cheliped with triangular carpal spur. Heterochely present: right dactylus linear, not curved, distally bent, reaching well beyond fixed finger claw; left dactylus curved, forming an arch, not reaching beyond fixed finger claw. Fixed finger in both chelae with bifid tooth, propodus about as long as broad, not enlarged.

Description. Female/neuter. Body ( Fig. 2 View FIGURE 2 A–B) length 1.2–2.2 mm, 8.6 times as long as broad. Cephalothorax ( Fig. 2 View FIGURE 2 A–C) 1.8 times as long as broad, narrowing towards frontal margin, lateral margins of anterior half crenulated, rostrum rounded. Pereonite 1 about 0.5 times as long as pereonite 2, pereonites 1–6 0.4, 0.7, 0.8, 1.0, 1.0, 0.7 times as long as broad respectively. Pleonites 1–5 as long as pereonites 5–6 and half of 4 together. Pleotelson ( Fig. 2 View FIGURE 2 A–B, D) as long as two pleonites, tapering posteriorly.

Antennule ( Fig. 2 View FIGURE 2 E) about as long as cephalothorax, three articled, with incipient articulation of a fourth terminal article. First article five times as long as broad, with two proximal setae, one simple and one penicillate, and a cluster of three penicillate and two simple subdistal setae; second article 0.2 times as long as first, with simple subdistal seta; third article 1.6 times as long as second, with one subdistal seta, distally with four simple and one penicillate setae and one aesthetasc.

Antenna ( Fig. 2 View FIGURE 2 F) six-articled, 0.5 times as long as antennule. First article short; second article about twice as long as broad, with one dorsodistal seta; third article about 0.5 times as long as second, with one dorsodistal seta; fourth article longer than articles 1–3 combined; with two penicillate and one simple subdistal setae; fifth article short, with one long distal seta; terminal article minute, with three setae.

Mouth parts. Labrum subtriangular, as long as labium. Labium ( Fig. 3 View FIGURE 3 B) bilobed, each lobe with minute distal process. Maxillule ( Fig. 3 View FIGURE 3 C) endite sigmoid, with dorsal setules, one seta, and eight spines distally. Left mandible ( Fig 3 View FIGURE 3 D) distal margin crenulated, lacinia mobilis broader distally, molar process weak and pointed. Right mandible ( Fig. 3 View FIGURE 3 E) as left but without distinct lacinia mobilis and with bifid incisor.

Maxilliped ( Fig. 3 View FIGURE 3 F) basis with seta near articulation with palp; palp first article naked, second article with three setae, third article with three setae, the most distal shorter, distal article with five setae.

Cheliped ( Fig. 3 View FIGURE 3 A) basis large, broader proximally; merus subtriangular, with ventral seta; carpus 1.5 times as long as broad, with dorsodistal seta; propodus about as long as carpus, with dorsodistal bifid crest, inner face with comb of four dendritic spines. Chela fixed finger well separated from rest of the chela by pronounced ventral invagination, forming neck; fixed finger overlapping claw, bearing one semicircular process, cutting edge weakly convex, almost straight, with three unequal setae, two long, ventral setae, and one seta near articulation with dactylus; dactylus narrow, curved, dorsally with nodules.

Pereopod 1 ( Fig. 4 View FIGURE 4 A) basis slender, 4.4 times as long as broad; ischium with seta; merus 0.4 times as long as basis, with ventral seta; carpus about as long as merus, with three setae, one longer. Propodus 0.9 times as long as carpus; dactylus and unguis 0.7 times as long as propodus.

Pereopod 2 ( Fig. 4 View FIGURE 4 B) coxa with seta; basis three times as long as broad; ischium with seta, merus distally expanded, with ventrodistal strong spine 0.7 times as long as carpus. Carpus distally expanded, 0.9 times as long as merus, ventral margin with three spinules, with one dorsodistal spine, one larger, serrated, ventrodistal spine and one very short spine; propodus cylindrical, ventral margin with several spinules, with one ventrodistal serrated spine and one ventrodistal minute spiniform process; dactylus and unguis 0.9 times as long as propodus.

Pereopod 3 ( Fig. 4 View FIGURE 4 C) very similar to pereopod 2, but basis shorter, 2.5 times as long as broad, with one penicillate seta.

Pereopod 4 ( Fig. 4 View FIGURE 4 D) basis 2.5 times as long as broad; ischium with two setae; merus slightly expended distally, with two ventrodistal spines; carpus cylindrical, slightly longer than merus, with one dorsodistal seta and four unequal spines, two shorter ventrally, and two longer dorsally; propodus 1.3 times as long as carpus, narrower, ventral margin with spinules, with two ventrodistal and one dorsodistal serrated spines and dorsodistal minute spiniform process; claw 2.7 times as long as propodus.

Pereopod 5 ( Fig. 4 View FIGURE 4 E) identical to pereopod 4.

Pereopod 6 ( Fig. 4 View FIGURE 4 F) similar to pereopod, 4–5, but propodus with four spines; claw with ventral serration.

Pleopods ( Fig. 4 View FIGURE 4 G) all similar; basal article as long as broad; exopod slightly longer, with eight plumose setae; endopod with one dorsal and seven terminal plumose setae.

Uropod ( Fig. 4 View FIGURE 4 H) about 2.1 times as long as pleotelson; basal article 1.9 times as long as broad; endopod proximal segment 1.3 times as long as basal article, with two penicillate and one simple subterminal setae; distal segment 1.1 times as long as proximal, with one medial seta and one penicillate and 4–5 simple terminal setae; exopod about as long as proximal endopod segment; proximal and distal segments subequal in length, proximal segment with one seta, distal segment with two terminal setae.

Male. Body ( Fig. 5 View FIGURE 5 A‒B) length 2.5–2.6 mm, 10.6 times as long as broad. Cephalothorax ( Fig. 5 View FIGURE 5 A‒C) 2.3 times as long as broad, narrowing towards frontal margin, rostrum rounded. Pereonite 1 about 0.5 times as long as pereonite 2, pereonites 1–6 respectively 0.5, 0.9, 1.0, 1.0, 1.0, 0.7 times as long as broad. Pleonites 1–5 as long as pereonites 4‒6 and half of 3 together, pleonites 1–2 0.6 times as long as broad, pleonites 3–4 about 0.8 times as long as broad, pleonite 5 as long as broad. Pleotelson ( Fig. 5 View FIGURE 5 A–B, D) slightly longer than preceding pleonite, tapering posteriorly, with a pair of normal setae and pair of penicillate setae.

Antennul e ( Fig. 5 View FIGURE 5 E) six-articled, with two peduncular articles and four flagellar segments, 0.8 times as long as cephalothorax. First peduncular article 3.7 times as long as broad, subproximally with one pair of penicillate setae, a tuft of three penicillate setae and one simple seta, subdistally with a tuft of three penicillate setae and one long simple seta; second peduncle article narrower, 0.2 times as long as first, 1.6 times as long as broad; flagellum segments 1–3 bearing four aesthetascs, fourth segment bearing one; first flagellar segment as long as broad, second 1.5 times as long as first, third 1.5 times as long as second, terminal article minute, with three terminal setae.

Antenna ( Fig. 5 View FIGURE 5 F) six articled, similar to that of the female.