Brasilana spelaea, Souza & Bento & Lima & Ferreira, 2025

Brasilana spelaea gen. nov. et sp. nov.

( Figs. 5–14 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 View FIGURE 11 View FIGURE 12 View FIGURE 13 View FIGURE 14 )

ZooBank: urn:lsid:zoobank.org:act:

Material examined. Holotype: male, 10.1 mm length, 3.3 mm width, dissected and drawn, mounted on slides with glycerin gelatin, 05º29’44.11’’S; 37º32’42.24’’W, Caverna da Água , Municipality of Governador Dix-Sept Rosado, Chapada do Apodi, Rio Grande do Norte, Brazil, coll. R. L. Ferreira. 19 September 2009 (ISLA 1359) GoogleMaps . Paratypes (same collection data) GoogleMaps : 1 female, dissected, mounted on slides with glycerin gelatin ( ISLA 1309) ; 8 females, one of them ovigerous, with 10 eggs, in 70% ethanol ( ISLA 1324, 1329, 1345, 1358, 1361, 1362, 1363 and 1364) ; 1 male, prepared for SEM observations ( ISLA 125938) .

Etymology. Name given as a reference to the Latin word spelaea , meaning “cave”.

Diagnosis. Same as the genus.

Description. Based on holotype male ( ISLA 1359) and paratypes male ( ISLA 125938) and female ( ISLA 1309). Body ( Fig. 5A View FIGURE 5 ) suboval, about 3 × longer than the greatest width at pereonite 5, unpigmented and translucent while alive, milky white in 70% ethanol; non-volvational. Head reniform ( Fig. 5A View FIGURE 5 ), anterior margin subtruncate, approximately 2.3 × wider than long, encapsulated laterally by pereonite 1; anophtalm. Coxae 2–7, furrows present ( Fig. 5B View FIGURE 5 ). Frontal lamina ( Figs. 5C View FIGURE 5 , 9A View FIGURE 9 ) narrow, slight hourglass shape, about 2.5 × longer than the greatest width, approximately 10% the width of the clypeus, reaching the middle of proximal part of the antennulae peduncles. Antennula ( Fig. 6A View FIGURE 6 ) reaching the middle of pereonite 1, with flagellum subequal in size to the peduncle; peduncle 3-articulate, with vestigial transversal suture ( Fig. 6A View FIGURE 6 , 9A View FIGURE 9 ) on the first article, which is bent at right angle; flagellum 7-articulate, apical article, the 7th, is like a tiny cone. Antenna ( Fig. 6C View FIGURE 6 ) a little less than half the total body length, peduncle 5-articulate, flagellum 28-articulate. Right mandible ( Figs. 6B View FIGURE 6 , 9C, E View FIGURE 9 ), molar anterior margin with 15 stout setae; with abundant long scale-setae; spine row composed of 9 spines; incisor 3-cuspidate, lateral cusp more developed and subacute. Left mandible ( Fig. 9B, D, F View FIGURE 9 ) palp article 2 about 5 × longer than wide, with 19 distolateral biserrate setae, article 3 suboval, with 13 plumose setae. Maxillula ( Figs. 6D View FIGURE 6 , 10D–E View FIGURE 10 ), lateral lobe well developed with 12 (left) / 13 (right) curved setae on distal margin; mesial lobe with 4 apical plumose setae. Maxilla ( Figs. 6E View FIGURE 6 , 10F View FIGURE 10 ) lateral lobe slightly longer than middle lobe, with 5 long distal plumose setae; middle lobe suboval, with 9 long plumose setae (5 dorsally placed, 4 ventral); mesial lobe well developed, bearing 12 plumose setae. Maxilliped ( Figs. 6F View FIGURE 6 , 10A–C View FIGURE 10 ) palp 6-articulate; article 2, mesial margin with 5 plumose setae, lateral margin naked; article 3, mesial margin with 14 plumose setae, lateral margin with 4 plumose setae; article 4, mesial margin with 12 plumose setae, lateral margin with 2 plumose setae, mediodistal lobe present; article 5, mesial margin naked, outer margin with 4 plumose setae, apical margin with 12 plumose setae; endite with 4 plumose setae and 2 coupling hooks.

Pereopods ( Fig. 7A–G View FIGURE 7 ) 1 raptorial, 2 semi-raptorial, 3-7 ambulatory, all with a conspicuous lobe on the distal dorsal corner of the basis, at the posterior face.

Pereopod 1 ( Figs. 7A View FIGURE 7 , 11A–D View FIGURE 11 ) raptorial, basis 3 × longer than wide, with 3 small slender setae on posterior margin; ischium 1.5 × as long as the greatest width, about 0.6 × the length of basis, posterior margin with 2 small slender setae; merus subrectangular, about 1.2 × wider than long, with 3 stout setae and 1 slender seta on posterior margin; carpus subtriangular, small, with a cluster of 6 setae (2 stout and 4 slender) on posterodistal corner; propodus about 2.2 × as long as greatest width, tapering distally, with 4 stout setae and 2 distal long slender setae; dactylus elongate, thick, about 0.75 × the length of propodus, nail present. Pereopod 2 ( Figs. 7B View FIGURE 7 , 11E–F View FIGURE 11 ) semi-raptorial, basis 3.3 × longer than wide, with 5 small slender setae on posterior margin; ischium 1.7 × as long as the greatest width, anterodistal corner with 2 stout setae, posterodistal corner with a cluster of 4 stout setae and 1 slender seta; merus 1.4 × longer than wide, subrectangular, posterior margin with 3 sets (1-3-3) of setae; carpus subrectangular, about 1.3 × longer than wide, posterior margin with 2 sets (2-3) of setae; propodus about 2.7 × as long as the greatest width, posterior margin with 3 sets (2-3-3) of setae; dactylus elongate, thick, about 0.85 × the length of propodus, nail present. Pereopod 3 ( Figs. 7C View FIGURE 7 , 12A–B View FIGURE 12 ) ambulatory, basis about 3.7 × longer than wide; ischium about twice as long as the greatest width, posterior margin with 3 slender setae, anterodistal and posterodistal corners with cluster of 3 setae each; merus subrectangular, about 1.8 × longer than wide, posterior margin with 3 setae, anterodistal and posterodistal corners with set of 3 stout setae each; carpus subrectangular, about 1.9 × longer than wide, posterior margin with a couple of stout setae, posterodistal corner with cluster of 3 setae; propodus about 3.4 × longer than wide, posterior margin with 3 couples of stout setae; dactylus about 0.75 × the length of propodus, nail present. Pereopod 4 ( Figs. 7D View FIGURE 7 , 12C–D View FIGURE 12 ) ambulatory, basis about 3.2 × longer than wide; ischium about 2.3 × as long as the greatest width, posterior margin with 3 slender setae, anterodistal and posterodistal corners with cluster of 3 setae each; merus subrectangular, about 1.7 × longer than wide, posterior margin with a proximal set of 3 setae, anterodistal and posterodistal corners with set of 3 stout setae each; carpus slightly elongate, about 4.3 × longer than wide, posterior margin with 3 sets (3-3-2) of stout setae; propodus about 5 × longer than wide, posterior margin with 3 sets of 3 stout setae; dactylus about 0.6 × the length of propodus, nail present. Pereopods 5–7 similar to each other, but consecutively and slightly longer than the previous one. Pereopod 5 ( Figs. 7E View FIGURE 7 , 12E View FIGURE 12 ) basis anterior margin with 7 minute setae; ischium 3.2 × as long as greatest width, anterodistal and posterodistal corners with cluster of 4 stout setae; merus about 2.2 × longer than wide, anterodistal corner with a cluster of 6 setae, posterodistal corner with a cluster of 4 stout setae; carpus about 3.2 × longer than broad, anterior margin with 2 sets of 3 setae, anterodistal corner with cluster of 5 setae, posterodistal corners with cluster of 6 setae (2 of them apically plumed); propodus elongate, about 6.1 × longer than wide, anterior margin with 2 sets (2-3) of setae; dactylus about 0.6 × the length of propodus, nail present. Pereopod 6 ( Fig. 7F View FIGURE 7 ) ambulatory, basis anterior margin with 6 minute setae; ischium about 3.5 × as long as the greatest width, anterodistal and posterodistal corners with cluster of 4 setae each; merus about 2.3 × longer than wide, anterodistal corner with cluster of 5 setae, posterodistal corner with cluster of 3 setae; carpus about 5.4 × longer than wide, anterior margin with 2 sets (2-3) of setae, anterodistal corner with cluster of 3 setae, posterodistal corner with cluster of 6 setae (2 of them apically plumed); propodus elongate, about 7.3 × longer than wide, anterior margin with 4 sets (1-1-3-2) of setae, anterodistal corner with cluster of 3 setae; dactylus about half the length of propodus, nail present. Pereopod 7 ( Fig. 7G View FIGURE 7 ) ambulatory, basis anterior margin with 7 minute setae; ischium about 4 × as long as the greatest width, anterior margin with 2 pairs of setae, anterodistal and posterodistal corners with cluster of 4 setae each; merus about 2.6 × longer than wide, anterior margin with a pair of setae, anterodistal corner with a cluster of 3 setae; carpus elongated, about 5.5 × longer than wide, anterior margin with 2 sets (1-3) of setae; propodus elongate, about 8.6 × longer than wide, anterior margin with 3 sets (1-2-2) of setae; dactylus about half the length of propodus, nail present.

Paired median penes on sternite 7, rounded to subcylindrical, with pores bordered by a thick crenulated layer ( Fig. 12F View FIGURE 12 ).

Pleonites ( Fig. 7A View FIGURE 7 ) 1–4 free, pleonite 5 covered laterally by pleonite 4, corresponding to Bowman’s (1975) “group b” pleonal segmentation pattern. Pleopod 1 ( Figs. 8A View FIGURE 8 , 13A–B View FIGURE 13 ) exopod about twice as long as wide, broadly rounded distally, margin of distal third with 36 plumose setae, mesial margin strongly convex; endopod about 2.8 × longer than wide, narrowly rounded distally, distal margin with 18 plumose setae, lateral margin slightly concave, naked, mesial margin almost straight, naked; peduncle 1.5 × wider then long, mesial margin with 5 coupling hooks. Pleopod 2 ( Figs. 8B View FIGURE 8 , 13C–D View FIGURE 13 ) exopod about 1.7 × longer than wide, broadly rounded distally, margin of distal half with 50 plumose setae, mesial margin strongly convex; endopod about 2.3 × longer than wide; appendix masculina inserted basally, longer than endopod, with parallel margins, slightly bent outwards in the distal half and subtruncate apex; peduncle 1.6 × wider then long, mesial margin with 4 coupling hooks, distolateral margin with acute spine. Pleopod 3 ( Figs. 8C View FIGURE 8 , 13E–F View FIGURE 13 ) exopod divided by transverse suture, about 1.4 × longer than wide, with 62 plumose setae; endopod about 1.7 × longer than wide, margin naked. Pleopod 4 ( Figs. 8D View FIGURE 8 , 14A–C View FIGURE 14 ) exopod divided by a transverse suture, similar to pleopod 3. Pleopod 5 ( Figs. 8E View FIGURE 8 , 14D–E View FIGURE 14 ) exopod divided by transverse suture, about 1.6 × longer than wide, with 40 plumose setae. Pleotelson ( Figs. 8F View FIGURE 8 , 14F View FIGURE 14 ) with smooth dorsal surface; large, slightly wider than long (considering the greatest width in the basal portion); posterior margin oval, crenulated, with 5 small stout setae and numerous plumose setae. Uropod ( Fig. 8G View FIGURE 8 ) rami subequal in length, extending beyond the distal end of the pleotelson; endopod lanceolate, apically truncate, about 1.3 × longer than the greatest width, mesial and lateral margins distally crenulated, marginal setae in single tier; exopod slender, about 5.5 × longer than the greatest width, outer margin with 3 sets (1-2-2) of small stout setae.

Females. 1 female ovigerous with 10 white eggs was observed ( Fig. 1C View FIGURE 1 ). Differing by the absence of the penial processes and appendix masculina.

Remarks. Based on the characters of the first article of the antennular peduncle and in the frontal lamina, B. spelaea gen. nov. et sp. nov. resembles to Politolana impressa (Harger, 1883) (compare with Figure 5 View FIGURE 5 in Riseman & Brusca 2002: 65). Brasilana spelaea gen. nov. et sp. nov. also superficially resembles both other species of Politolana and Natalolana in these respects. Politolana and Natalona are Conilerinae marine epigean genera, and in the molecular phylogeny presented here, together with C. harfordi , represent the sister-group of B. spelaea gen. nov. et sp. nov. (as mentioned above). Politolana was found to be paraphyletic by Riseman & Brusca (2002). They also focused on the possible paraphyletic nature of Natatolana . In the phylogeny presented here, Natatolana appears as monophyletic. Both, Politolana and Natatolona include Brazilian species – P. tricarinata Riseman, Pires-Vanin & Brusca, 2001 and P. eximia (Hansen, 1890) from São Sebastião coast, Ubatuba, southeastern Brazil ( Riseman et al. 2001) and N. gracilis (Hansen, 1890) from several localities off northern Brazil (Kensley & Shotte 1989). Although the frontal lamina and antennule are similar in some aspects in the 3 genera, B. spelaea gen. nov. et sp. nov. differs from Politolana and Natatolana in many respects. Brasilana spelaea gen. nov. et sp. nov. differs from Politolana e.g., by the absence of small secondary ungui on dactyli; by possessing only pereopods 2–3 ischium produced anterodistally; by the absence of biplumose setae on all pleon epimeres or just simple setae confined to the third pleonite; and by the uropod endopod of adults without notch in distolateral margin (see Riseman & Brusca 2002). Brasilana spelaea gen. nov. et sp. nov. differs from Natatolana e.g., by anophthalmia, absence of head rostral point, and mainly the absence of long plumose setae on the pereopod 7 basis.