Politolana cleoniceae, Paiva & Souza-Filho, 2023

Paiva, Ricardo J. C. & Souza-Filho, Jesser F., 2023, Three new species of the family Cirolanidae Dana, 1852 (Isopoda, Cymothoida) from the shallow Brazilian bathyal, Zootaxa 5319 (1), pp. 1-26 : 19-24

Politolana cleoniceae spec. nov.

( Figs 13–17 )

Material examined. Holotype: female, 45.5 mm, (dissected and drawn, dissected appendages in alcohol 75%), Pernambuco, Continental Shelf , baited bottom traps, 8°30’07.5”S, 34°41’37.7”W, 307 m, 06 October 2015, MOUFPE 15530 .

Type locality. Brazil, 8°30’07.5”S, 34°41’37.7”W.

Etymology. Named in honour of Cleonice Peres de Carvalho, mother of first author.

Diagnosis. Head interocular furrow present, submarginal sulcus present, incomplete dorsal groove. Antenna 1 not reaching pereonite 1. Antenna 2 reaching pereonite 1 posterior margin. Pereopods 1–4 basis without plumose marginal setae. Pereopod 7 merus with anterodistal angle rounded and very expanded. Pleonite 1 visible. Pleotelson as long as wide, smooth, apex truncated with a subacute medial process, distal margin with plumose setae, or with 2 RS.

Description of female holotype. Body 2.8 times as long as greatest width, dorsal surfaces smooth, widest at pereonite 6, lateral margins slightly convex. Rostral point absent, frontal margin rounded. Eyes separated by about 80% head width, eye colour white. Pereonite 1 and coxae 2–3 each with posteroventral angle rounded; coxae 4–7 with entire oblique carina; pereonites 5–7 posterior margins smooth. Pleon with pleonite 1 not concealed by pereonite 7, pleonites 2–5 posterior margin smooth; pleonite 2 posterolateral angles forming subacute point, not posteriorly produced; pleonite 3 posterolateral margins not extending to pleonite 5 posterior margin, acute; pleonite 4 posterolateral margin acute extended beyond pleonite 5 posterior margin; pleonite 5 with posterolateral angles overlapped by pleonite 4 lateral margin. Pleotelson shorter than anterior width (0.74 times); without longitudinal carina; without dense patch of setae; lateral margins convex, smooth; posterior margin broadly rounded with a middle subacute process, with plumose setae, and a row of RS.

Antenna 1 peduncle articles 1 and 2 distinct, articulated, article 2 0.3 times as long as article 1, article 3 and 4 0.8 times as long as combined lengths of articles 1 and 2, article 3 1.3 times as long as wide; flagellum moderately inflated, with 20 articles, extending beyond eye midway. Antenna 2 peduncle article 4 almost as long as wide, 1.45 times as long as article 3, with 6 short simple setae (distal); article 5 1.8 times as long as article 4, 2.8 times as long as wide, anterodistal angle with cluster of 3 short simple seta; flagellum with 31 articles, extending to pereonite 3.

Frontal lamina 3.75 times longer than greatest width, lateral margins straight, slightly widening anteriorly, not visible in dorsal. Mandible molar process anterior margin with more than 20 flat teeth; without proximal cluster of long simple setae; right mandible spine row composed of 12 spines; palp article 2 with 17 distolateral setae, article 3 with 24 slender setae. Maxillula mesial lobe with 3 large CPS RS; lateral lobe with 10 RS. Maxilla lateral lobe with 2 long simple setae; middle lobe with 16 long simple setae; mesial lobe with 2 simple setae and 12 distal pappose setae. Maxilliped palp article 1 mesial margin without setae, lateral margin without setae; article 2 mesial margin with 6 slender setae, lateral margin with 9 simple setae; article 3 mesial margin with 10 slender setae, lateral margin with 19 slender setae; article 4 mesial margin with 9 slender setae, lateral margin with 12 simple setae; article 5 distal margin to mesial margin with 16 simple setae, lateral margin with 6 simple setae; endite with 5 long CPS and 2 coupling setae.

Pereopod 1 basis 3 times as long as greatest width, superior margin setose, superior distal angle without cluster of setae, inferior margin without setae, inferior distal angle with a cluster of 4 long and slender setae; ischium 1.5 times as long as basis, inferior margin with 12 simple setae, inferior distal margin without setae, superior margin with a middle cluster of 6 simple setae, superior distal margin not produced over merus and with a line of long and slender setae; merus inferior margin with a row of 6 simple setae, superior distal angle produced and reaching 1/2 of carpus, superior margin with a row of both simple and RS; carpus inferior margin with 4 setae, inferior distal angle without setae; propodus 4.1 times as long as wide, inferior margin with 9 simple setae and 2 RS, inferior distal margin with 1 RS and 3 simple setae, superior distal margin with 4 short setae; dactylus 0.5 times as long as propodus. Pereopod 2 ischium inferior margin with 6 long simple setae, inferior distal margin with 6 simple setae, superior distal margin not produced over merus and with a cluster of long and slender setae, mesial margin with a cluster of long and slender setae; merus inferior margin with 1 stout RS, inferior distal margin with 2 RS, superior distal angle produced and reaching 1/4 of propodus, superior margin with a row of both long and simple; carpus inferior margin with 7 stout RS, inferior distal margin with 3 long acute RS; propodus 1.45 times as long as wide, inferior margin without setae, inferior distal margin with 1 short RS and 2 simple setae; dactylus 0.9 times as long as propodus. Pereopod 3 similar to pereopod 2. Pereopods 4–6 similar to each other. Pereopod 7 basis inferior distal angle with a 7 long and plumose setae; superior margin and facial middle line densely setose (plumose setae); basis slightly ovate, 2 times as long as greatest width; ischium 0.5 times as long as basis, 1.5 times as long as wide, widened distally; merus 0.6 times as long as ischium, 1.4 times as long as wide; carpus 0.8 times as long as ischium, 2.4 times as long as wide; propodus 1.2 times as long as ischium, 6 times as long as wide, inferior margin with 4 RS; dactylus 0.45 times as long as propodus.

Pereon-pleon articulation tight, with pleonite 1 visible, not completely overlapped by pereonite 7. Pleopod 1 exopod 1.7 times as long as wide, lateral margin convex, distally broadly rounded with distolateral notch, with PMS from entire lateral to distal one-third mesial margin, with ~60 PMS; endopod 1.5 times as long as wide, distally narrowly rounded, with PMS from distal one-third, mesial margin with PMS from distal one-third, endopod with ~40 PMS; peduncle 0.4 times as wide as long, mesial margin with 5 coupling setae. Pleopod 2 exopod with ~90 PMS, endopod with ~30 PMS. Pleopod 3 exopod with incomplete suture, with ~100 PMS, endopod with ~20 PMS. Pleopod 4 exopod with incomplete suture, with ~80 PMS, endopod with ~20 PMS. Pleopod 5 exopod with incomplete suture, with ~35 PMS from distal two-third, endopod with 7 PMS distally. Pleopods 2–5 endopod distal margin with rounded.

Uropod peduncle ventrolateral margin with 7 PMS, posterior lobe 0.9 times as long as endopod; rami slightly shorter than pleotelson, lateral, distal and mesial margin lined with long PMS. Endopod apically acute; lateral margin convex, without prominent excision; mesial margin almost straight. Exopod not extending to end of endopod, 4.4 times as long as greatest width, apically acute; lateral and mesial margin straight, lateral margin with 6 RS.

Distribution. Known only from the type locality, off Pernambuco state ( Brazil), at 307 m depth ( Fig. 7 ).

Remarks. Politolana cleoniceae spec. nov. is closest to Politolana haneyi Riseman & Brusca, 2002 , especially considering features such as the close pereon–pleon articulation, in which pleonite 1 is visible, and is not overlapped completely by pereonite 7, with the pleon arched (in the dorsal–ventral view) in a uniform sequence with the pereon, and the endopod of the uropod being shorter than the exopod. However, the new species can be differentiated from P. haneyi by the following combination of characters (the characters of P. haneyi are shown within parentheses): antenna 2 does not reach the posterior margin of pereonite 1 (vs. reaches the anterior margin of pereonite 3), coxa 7 slender with a visible lateral oblique suture (vs. suture absent), basis of pereopods 1–4 with no stout CPS (vs. with 6-7 stout CPS), anterodistal angle of the menus of pereopod 7 rounded and very expanded (vs. straight, expanded discreetly), the endopod of the uropod with no cluster of long distal setae and distomedial margin excavated at an angle of approximately 90° (vs. clusters of long distal setae present and distomedial margin concave), internal basolateral angle of pleopod 5 with no lobe (vs. a long hook-shaped lobe near the peduncle), pleotelson with rounded distal margin bearing a medial distal spine with a robust seta on each side (vs. distal margin with no distal medial spine, but four robust distal setae).

Figures

FIGURE 7. Map showing distribution of the species: D. brucei (= circle), Dolicholana ivanyae spec. nov. (= square), Natatolana hadassae spec. nov. (= star) and Politolana cleoniceae spec. nov.(= pentagon).

FIGURE 13. Politolana cleoniceae spec. nov., Holotype, female, 45.5 mm, (MOUFPE 15530). A = habitus dorsal view; B = habitus lateral view. Scale bars 5 mm.

FIGURE 14. Politolana cleoniceae spec. nov., Holotype, female, 45.5 mm, (MOUFPE 15530). A = Maxilla 1; B = Maxilla 2; C = Antenna 1; D = Antenna 2; D = Maxilliped; E = Mandible; F = Frontal lamina. Scale bars: A–E = 1 mm, F = 2 mm.

FIGURE 15. Politolana cleoniceae spec. nov., Holotype, female, 45.5 mm, (MOUFPE 15530). A–D = Pereopods 1–4. Scale Scale bars 3 mm.

FIGURE 16. Politolana cleoniceae spec. nov., Holotype, female, 45.5 mm, (MOUFPE 15530). Scale bars 5 mm. A–C = Pereopods 1–3; D = Pleonites 1–5; E = Pleotelson. Scale bars: A–C = 3 mm, D= 5 mm, E = 2 mm.

FIGURE 17. Politolana cleoniceae spec. nov., Holotype, female, 45.5 mm, (MOUFPE 15530). A–E = Pleopods 1–5; F = Uropod. Scale bars: A–E = 3 mm; F = 2 mm.