Paraleucilla sphaerica, Lanna, Emilio, Cavalcanti, Fernanda F., Cardoso, Lilian, Muricy, Guilherme & Klautau, Michelle, 2009

Lanna, Emilio, Cavalcanti, Fernanda F., Cardoso, Lilian, Muricy, Guilherme & Klautau, Michelle, 2009, Taxonomy of calcareous sponges (Porifera, Calcarea) from Potiguar Basin, NE Brazil, Zootaxa 1973, pp. 1-27 : 19-23

Paraleucilla sphaerica sp. nov.

Diagnosis. Paraleucilla with spherical or subspherical shape, colour white or beige, and skeletal architecture typical of the genus; its most remarkable characteristic is the presence of microdiactines in the choanosomal skeleton.

Type material. (EXAMINED) HOLOTYPE: UFPEPOR 417, station A21 (04°57’49.7”S – 36°19’16.1”W), depth: 13–14 m, coll. R/V Astro Garoupa, trawling, 19/V/2004. PARA- TYPES: UFPEPOR 430, station A12 (04°58’20.8”S – 36°27’39.5”W), depth: 11–12 m, coll. R/V Astro Garoupa, trawling, 21/V/2004; UFPEPOR 564, near station A16 (04°48’08.8”S – 36°26’38.5”W), depth 20 m, coll. G. Muricy, SCUBA, 03/III/2007.

Type locality. Potiguar Basin, Rio Grande do Norte state, Brazil.

Etymology. from Latin sphaera (= sphere, globe). It refers to the spherical shape of most specimens.

Description. White or beige alive and in ethanol. The largest specimen collected measures 0.5 x 0.5 x 0.4 cm. This species has a subspherical to spherical shape (Fig. 8A) with one apical osculum surrounded by a fringe of trichoxeas (Fig. 8B). The surface is smooth, but rough to touch and the consistency is brittle. The atrium is small and has circular openings of the exhalant canals of the leuconoid aquiferous system. Choanocyte chambers are spherical. The cortical skeleton is composed of the basal system of tetractines (Fig. 8C). The choanosomal skeleton is divided in an inarticulate region (outer region) and a zone without organisation (inner region) (Fig. 8D). The outer region is formed by the apical actine of the cortical tetractines and by the unpaired actine of subatrial triactines and few tetractines (Fig. 8E). The inner region has scattered triactines and tetractines similar to those of the subatrial skeleton (Fig. 8F). Microdiactines are also common in this inner region (Fig. 8G), but they were sometimes found also in the cortex. The atrial skeleton is composed of triactines and tetractines. The apical actine of the tetractines penetrates the atrial cavity (Fig. 8F).

Spicules ( Table 7). Cortical tetractines: sagittal. Paired actines are longer than the unpaired one. Actines are conical and sharp. The apical actine is conical, undulated, sharp, and slightly longer than the basal actines [paired actines: 125.1–352.1 (±41.5)–600.0 / 35.3 (±4.5) µm (n = 3 specimens)], [unpaired actine: 152.9–376.6 (±28.6)–583.8 / 36.1 (±3.6) µm (n = 3 specimens)], [apical actine: 125.1–422.1 (±68.8)–653.3 / 39.9 (±6.9) µm (n = 3 specimens)] (Figs. 9A, B). Subatrial triactines: sagittal. These spicules are more abundant than the subatrial tetractines. Paired actines are shorter than the unpaired one. Actines are conical, straight, and sharp. Sometimes the paired actines are undulated [paired actines: 111.2–248.2 (±7.3)–514.3 / 18.0 (±0.7) µm (n = 3 specimens)], [unpaired actine: 166.8–354.0 (±31.5)–639.4 / 20.8 (±0.5) µm (n = 3 specimens)] (Fig. 9C). Subatrial tetractines: sagittal. Basal actines are almost the same size. They are conical, slightly undulated or straight, and sharp. The apical actine is conical, smooth, undulated, and sharp [paired actines: 194.6–331.5 (±39.7)–514.3 / 30.0 (±5.2) µm (n = 3 specimens)], [unpaired actine: 152.9–349.6 (±28.1)–528.2 / 31.8 (±3.8) µm (n = 3 specimens)], [apical actine: 41.7–80.6 (±9.7)–166.8 / 25.4 (±5.2) µm (n = 3 specimens)] (Fig. 9D). Atrial triactines: sagittal. Paired actines are longer than the unpaired one. Actines are cylindrical and sharp, and the paired actines are slightly undulated while the unpaired one is straight [paired actines: 97.3–164.2 (±12.0)–264.1 / 15.6 (±1.3) µm (n = 3 specimens)], [unpaired actine: 55.6–127.9 (±3.0)–208.5 / 14.6 (±1.1) µm (n = 3 specimens)]. Atrial tetractines: sagittal. Paired actines are longer than the unpaired one. Actines are cylindrical and sharp, and the paired actines are slightly undulated while the unpaired one is straight. The apical actine is conical, smooth, straight or curved, and sharp [paired actines: 97.3–245.6 (±31.1)–347.5 / 10.5 (±1.6) µm (n = 3 specimens)], [unpaired actine: 83.4–205.7 (±12.7)–361.4 / 11.2 (±1.5) µm (n = 3 specimens)], [apical actine: 27.8–61.0 (±13.5)–139.0 / 8.7 (±0.6) µm (n = 3 specimens)] (Fig. 9E). Choanosomal and cortical microdiactines: fusiform, undulated, and sharp [94.5–177.5 (±5.8)–315.0 / 9.0 (±1.2) µm (n = 3 specimens)] (Fig. 9F). Trichoxeas: very thin, straight spicules [208.5–476.5 (±61.9)–722.8 / 5.0 (±0.8) µm (n = 3 specimens)].

Ecology. This species was found associated to the calcareous algae Bryothamniom triquetum.

Remarks. Paraleucilla sphaerica sp. nov. is similar to four known species: P. proteus (Dendy, 1913) , P. crosslandi ( Row, 1909) , P. princeps ( Row & Hôzawa, 1931) , and P. perlucida Azevedo & Klautau, 2007 . The species most similar to P. s p h a e r i c a sp. nov. is P. proteus . Both have the same spicular composition, but the presence of microdiactines in the cortical and choanosomal skeletons of P. sphaerica sp. nov. distinguishes them. Additionally, subatrial triactines and cortical tetractines are larger in the new species than in P. proteus . P. crosslandi has triactines and two types of tetractines in the cortical skeleton, while P. sphaerica sp. nov. has no triactines and only one type of cortical tetractines. Also, P. crosslandi possesses only triactines in the subatrial skeleton and in the organized zone, while P. sphaerica sp. nov. has both triactines and tetractines.

FIGURE 8. Paraleucilla sphaerica sp. nov. (UFPEPOR 417). A—preserved holotype; B—detail of the oscular fringe composed of trichoxeas; C—tangential section of the cortex; D—transversal section of the body (ir—inner region, or—outer region); E—transversal section of the outer region; F—transversal section of the inner region (at—atrium); G— microdiactines in the choanosome (arrowheads).

FIGURE 9. Spicules of Paraleucilla sphaerica sp. nov. (UFPEPOR 417) A, B—cortical tetractine; C—subatrial triactine; D—subatrial tetractine; E—atrial tetractine; F—microdiactine (p—paired actines, u—unpaired actine, a —apical actine).

P. princeps resembles P. sphaerica sp. nov. by the presence of giant tetractines. They differ, however, in the fact that P. princeps has also giant diactines and small triactines in the cortical skeleton, both absent in P. sphaerica sp. nov. P. p e r l u c i d a also can be differentiated from the new species by the presence of giant diactines, as well as by the absence of microdiactines. The other three species of the genus [ P. magna Klautau, Monteiro & Borojevic, 2004 , P. saccharata ( Haeckel, 1872) and P. c u c u m i s ( Haeckel, 1872)] can be easily distinguished from P. sphaerica sp. nov. by the presence of exclusively triactines in the atrial skeleton.

Spicule Actine Length Width n

Min Mean s Max Mean s Cortical tetractines

UFPEPOR 417 (H) paired 225.0 320.0 79.5 600.0 29.5 8.3 30 UFPEPOR 430 (P) 125.1 325.7 71.4 444.8 35.9 12.4 30 UFPEPOR 564 (P) 278.0 410.7 73.0 528.2 40.6 10.4 20 All specimens 125.1 352.1 41.5 600.0 35.3 4.5 - UFPEPOR 417 (H) unpaired 165.0 358.5 65.3 480.0 31.5 7.2 30 UFPEPOR 430 (P) 152.9 354.5 79.5 486.5 36.4 11.1 30 UFPEPOR 564 (P) 208.5 417.0 108.7 583.8 40.3 8.9 20 All specimens 152.9 376.6 28.6 583.8 36.1 3.6 - UFPEPOR 417 (H) apical 333.6 453.1 76.8 597.7 33.1 8.1 30 UFPEPOR 430 (P) 125.1 326.7 117.1 528.2 37.2 8.2 30 UFPEPOR 564 (P) 333.6 486.5 98.4 653.3 49.3 8.4 20 All specimens 125.1 422.1 68.8 653.3 39.9 6.9 - Subatrial triactines

UFPEPOR 417 (H) paired 139.0 243.2 54.3 361.4 17.6 7.2 30 UFPEPOR 430 (P) 111.2 242.8 61.7 389.2 17.4 5.2 30 UFPEPOR 564 (P) 166.8 258.5 80.3 514.3 19.0 9.5 30 All specimens 111.2 248.2 7.3 514.3 18.0 0.7 - UFPEPOR 417 (H) unpaired 180.7 337.7 89.7 528.2 20.4 7.9 30 UFPEPOR 430 (P) 166.8 326.2 60.7 430.9 20.5 5.3 30 UFPEPOR 564 (P) 194.6 398.0 99.9 639.4 21.5 10.0 30 All specimens 166.8 354.0 31.5 639.4 20.8 0.5 - Subatrial tetractines

UFPEPOR 417 (H) paired 194.6 321.5 67.3 444.8 27.8 5.7 30 UFPEPOR 430 (P) 194.6 288.7 55.0 417.0 25.0 5.7 30 UFPEPOR 564 (P) 222.4 384.3 89.8 514.3 37.2 10.4 20 All specimens 194.6 331.5 39.7 514.3 30.0 5.2 - UFPEPOR 417 (H) unpaired 236.6 344.2 64.0 472.6 29.6 5.1 30 UFPEPOR 430 (P) 208.5 318.3 60.2 458.7 28.6 4.4 30 UFPEPOR 564 (P) 152.9 386.4 92.2 528.2 37.2 10.4 20 All specimens 152.9 349.6 28.1 528.2 31.8 3.8 - UFPEPOR 417 (H) apical 41.7 89.9 32.6 166.8 22.2 5.9 30 UFPEPOR 430 (P) 41.7 67.2 22.5 125.1 21.3 5.5 30 UFPEPOR 564 (P) 41.7 84.8 35.5 166.8 32.7 8.5 20 All specimens 41.7 80.6 9.7 166.8 25.4 5.2 - Atrial triactines

UFPEPOR 417 (H) paired 125.1 174.2 34.1 250.2 14.8 3.5 30 ......continue Spicule Actine Length Width n

Min Mean s Max Mean s

UFPEPOR 430 (P) 111.2 171.0 30.8 236.3 14.5 2.8 30 UFPEPOR 564 (P) 97.3 147.3 39.9 264.1 17.4 4.9 20 All specimens 97.3 164.2 12.0 264.1 15.6 1.3 80 UFPEPOR 417 (H) unpaired 69.5 124.1 29.1 166.8 15.7 4.8 30 UFPEPOR 430 (P) 55.6 128.3 34.8 208.5 15.0 2.2 30 UFPEPOR 564 (P) 69.5 131.3 39.7 208.5 13.1 2.5 20 All specimens 55.6 127.9 3.0 208.5 14.6 1.1 - Atrial tetractines

UFPEPOR 417 (H) paired 152.9 265.9 44.8 347.5 9.5 3.4 30 UFPEPOR 430 (P) 125.1 201.6 42.5 319.7 12.8 2.3 30 UFPEPOR 564 (P) 97.3 269.2 50.4 333.6 9.3 3.3 30 All specimens 97.3 245.6 31.1 347.5 10.5 1.6 - UFPEPOR 417 (H) unpaired 97.3 223.3 58.6 347.5 10.4 3.5 30 UFPEPOR 430 (P) 83.4 194.1 61.4 333.6 13.2 2.0 30 UFPEPOR 564 (P) 83.4 199.7 68.9 361.4 9.9 3.5 30 All specimens 83.4 205.7 12.7 361.4 11.2 1.5 - UFPEPOR 417 (H) apical 41.7 73.6 17.5 111.2 8.5 3.0 30 UFPEPOR 430 (P) 27.8 42.2 11.2 69.5 8.0 2.0 30 UFPEPOR 564 (P) 41.7 67.2 26.3 139.0 9.5 3.4 30 All specimens 27.8 61.0 13.5 139.0 8.7 0.6 - Trichoxea

UFPEPOR 417 (H) 403.1 546.3 93.7 722.8 5.5 2.4 20 UFPEPOR 430 (P) 262.5 395.9 68.0 546.0 3.9 1.1 30 UFPEPOR 564 (P) 208.5 487.2 126.7 695.0 5.6 1.9 20 All specimens 208.5 476.5 61.9 722.8 5.0 0.8 - Microdiactine

UFPEPOR 417 (H) 94.5 173.2 69.2 252.0 7.3 2.6 0 6 UFPEPOR 430 (P) 94.5 185.7 53.9 315.0 9.8 2.3 30 UFPEPOR 564 (P) 115.5 173.6 37.7 231.0 9.8 1.0 13 All specimens 94.5 177.5 5.8 315.0 9.0 1.2 - The genus Paraleucilla has now three species known from the Atlantic Ocean, all of them occurring in the Brazilian coast: P. magna from Rio de Janeiro ( Klautau et al. 2004) and P. perlucida from Angra dos Reis ( Azevedo & Klautau 2007), both in Rio de Janeiro state, and P. sphaerica sp. nov. from Rio Grande do Norte state. All other five species of Paraleucilla ( P. proteus , P. crosslandi , P. princeps , P. saccharata , and P. cucumis ) are distributed in the Indo-Pacific region.