Brasilana, Souza & Bento & Lima & Ferreira, 2025

Genus Brasilana gen. nov.

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

Type species. Brasilana spelaea gen. nov. et sp. nov., by monotypy and original designation.

Generic diagnosis. Non-volvational, anophtalm, translucid. Frontal lamina approximately 4 × longer than wide. Antennula peduncle 3-articulate, first article cylindrical and bending at almost right angle; antennular flagellum 7-articulate. Maxillula lateral lobe well developed with curved setae on distal margin; mesial lobe with 4 apically plumed setae. Maxilla mesial lobe well developed. Mandibular incisor 4-cuspidate, lateral cusp more developed and subacute. Maxilliped endite with 2 plumose setae and 1 coupling hook. Conspicuous distal lobe present on pereopods 1-7 basis. Paired median penes. Pleonites 1-4 free. Appendix masculina basally inserted. Uropod endopod lanceolate, apically truncate, about 1.3 × longer than greatest width, bearing simple setae; exopod approximately 5.5 × longer than wide, lateral margin with 3 sets (1-2-2) of small stout setae. Pleotelson distal margin with 5 small stout setae and numerous plumose setae.

Etymology. The generic name is a combination of Brasi (Latin) + (Ciro) lana. Gender, feminine.

Remarks. Brasilana gen. nov. is characterized by having an antennular peduncle, that originally consists of 4 articles, compounded by 3 articles, since the first 2 articles are completely fused, the second article (originally the 3 rd), slender, is slightly longer than the 1 st one which is bent at almost right angle, and the fourth article is vestigial. This special configuration of the 1 st article of the antennular peduncle of Brasilana gen. nov. is different from that of all the other Cirolaninae genera. In none of them does the 1 st article (corresponding to the first 2 original articles) bend at a right angle. That is, in Brasilana gen. nov., the 1 st article is not collinear with the last articles of the antennular peduncle as in all other Cirolaninae genera; instead, it is “geniculate” (article 2 at right angles to article 1), as referred by Keable (2006: 139). Yet, in Brasilana gen. nov., unlike in the Cirolaninae genera, the 1 st article is cylindrical throughout, there is no broad base, and it is “nearly sphaerical” as described for Cirolanides texensis (see Benedict 1896). It is possible to observe a vestigial transverse suture in the place where the 1 st article of the antennula bends ( Fig. 6A View FIGURE 6 , 9A View FIGURE 9 ). In some species of Haptolana – e.g., H. trichostoma , H. pholeta Bruce & Humphreys, 1993 , and H. bowmani , there is a fusion of the first 2 original articles of the antennular peduncle, but they are colinear (and in H. bowmani the fusion is indicated by a longitudinal, not a transverse, line). In Brasilana gen. nov., the 3 rd article of the antennula (which corresponds to the 4 th original) is extremely short, as is normally the case in many genera. In Cirolanidae , this 3 rd /4 th article has already been interpreted as a “very well apical zone of the distal peduncular article of AI” or “strongly individualized distal zone” for Haptolana (see Botosaneanu & Iliffe 2000), duly recognized as the 4 th article for other species of Haptolana (see Bruce & Humphreys 1993), ignored in descriptions, e.g., for Antrolana lira Bowman, 1964 and Kensleylana briani Bruce & Herrando-Pérez, 2005 , and described as the “1 st one very small” article of flagellum for Arubolana rotunditelson Botosaneanu and Stock, 1979 ( Botosaneanu & Iliffe 2010: 5). As made clear by Riseman & Brusca (2002: 68), “Brusca & Wilson (1991) suggested that the minute fourth article of the antennule might not be peduncular”. However, we agree with Riseman and Brusca and regard it as part of the peduncle.

Brasilana gen. nov. also has a conspicuous lobe on the distal dorsal corner in the posterior face at the basis of all pereopods 1–7 which is interpreted here as unique in Cirolaninae .

Brasilana gen. nov. can be distinguished from each of the Cirolaninae as follows: 1. Antrolana : antennular flagellum compound by 7 articles ( vs. 12–18), antenna peduncle 5-articulate ( vs. 6-articulate), pereonites with posteroventral corners moderately produced on pereonites 1–3 and very produced on pereonites 4–7 ( vs. without posteroventral corners on pereonites 1–3 and with posteroventral corners only moderately produced on pereonites 4–7); 2. Arubolana : pereopod 2 semi-raptorial ( vs. strongly raptorial), male pleopod 2 appendix masculina inserted basally ( vs. inserted sub-basally); 3. Cirolana : antenulla peduncle articles 1 and 2 combined lengths less than article 3 length ( vs. lengths greater than article 3 length), frontal lamina size approximately 10% of the width of clypeus ( vs. c. 40% of the width of clypeus), frontal lamina narrow, hourglass shape ( vs. wide, pentagonal or subquadrate), pereopod 1 merus with acute robust setae ( vs. with tubercular robust setae), pereopods 1 raptorial, 2–3 semi-raptorial, 4–7 ambulatory ( vs. all ambulatory – not always); 4. Cirolanides : antennula peduncle 3-articulate ( vs. 4-articulate considering that what is interpreted as the 1 st article of the flagellum, is, actually, the distal article of the peduncle), flagellum of antennulae short ( vs. elongated), pleonite 5 covered laterally by pleonite 4, without free lateral margins ( vs. not covered, with free lateral margins), posterior margin of pleotelson oval ( vs. truncate with medial concavity or well-rounded); 5. Creasseriella: antennula peduncle 3-articulate ( vs. 2-articulate), only pleonite 5 without free lateral margins ( vs. pleonites 4- 5 without free lateral margins), posterior margin of pleotelson oval ( vs. well-rounded); 6. Haptolana : pereopods 1 raptorial, 2–3 semi-raptorial, 4–7 ambulatory ( vs. 1–7 raptorials); 7. Mexilana : antennula peduncle 3-articulate ( vs. 4-articulate considering that what is interpreted as the 1 st article of the flagellum, is, actually, the distal article of the peduncle), pereopods 1 raptorial, 2–3 semi-raptorial, 4–7 ambulatory ( vs. pereopods 1–2 weakly raptorial, pereopods 3–7 ambulatory), pleonites 1–5 complete, the 5 th without free lateral margins and covered by pleonite 4 ( vs. 1–3 complete, pleonite 4 covered laterally by pleonite 3; pleonite 5 with central half separated from pleotelson by suture, lateral parts fused with pleotelson); 8. Speocirolana : maxilliped endite with 2 plumose setae and 1 coupling hook ( vs. with 13 long, plumose setae and 2 coupling hooks), pereopods 1 raptorial, 2–3 semi-raptorial ( vs. 1–3 strongly raptorials), uropodal protopod not reaching beyond the posterior margin of the pleotelson; without acute tip ( vs. reaching (or not) beyond the posterior margin of the pleotelson; ending posteriorly in acute tip); 9. Sphaerolana : be unable to roll into a ball ( vs. be able to roll into a ball), pleonites 3–5 visible ( vs. no evidence of pleonites 3–5), pereopods 1 raptorial, 2–3 semi-raptorial ( vs. pereopods 1–3 raptorial, pereopod 1 less so than the stouter 2–3), exopods of pleopods 3–5 divided by a suture ( vs. exopods of pleopods 4–5 partially divided by a suture); 10. Yucatalana : large cirolanid – 11 mm ( vs. very small – 3-4 mm), head reniform, with anterior margin subtruncate, without rostrum ( vs. head with round lateral bulges and rather well developed rostrum), appendix masculina inserted basally ( vs. appendix masculina subbasally inserted, with capitate apex preceded by short row of minute “ teeth”), paired, rounded/cylindrical, penes ( vs. a single hemispherical penis); 11. Zulialana : large cirolanid – 11 mm ( vs. very large – 30 mm), unable to roll into a ball ( vs. able to roll almost perfectly into a ball), pleonites 1–5 visible, pleonite 5 covered laterally by pleonite 4 ( vs. coalescence of the pleonal segments with the telson almost complete), exopods of pleopods 3–5 divided by a suture ( vs. all exopods of pleopods without suture).