Leucetta floridana, HAECKEL, 1872

Cóndor-Luján, Báslavi, Louzada, Taynara, Hajdu, Eduardo & Klautau, Michelle, 2018, Morphological and molecular taxonomy of calcareous sponges (Porifera: Calcarea) from Curaçao, Caribbean Sea, Zoological Journal of the Linnean Society 183 (3), pp. 459-525 : 483-486

LEUCETTA FLORIDANA HAECKEL, 1872

( FIG. 12 ; TABLE 10)

Synonymy: Amphoriscus floridanus , Dyssycus floridanus , Leucaltis floridana , Leucaltis impura , Leucaltis pura , Lipostomella floridana Haeckel, 1872: 144 ; Leucilla floridana Jenkin, 1908: 453 ; Leucetta floridana de Laubenfels, 1950: 146 ; Leucetta microraphis Borojevic & Peixinho, 1976: 1003–1005 ; Leucetta aff. floridana Lehnert & Van Soest, 1998: 99 ; Leucetta floridana Valderrama et al., 2009: 9–14 ; Lanna et al., 2009: 7–9; Muricy et al., 2011: 36–37; Rützler et al., 2014: 102; Pérez et al., 2017: 13; Azevedo et al., 2017: 333–334, 336.

Type specimen: Haeckel’s type material of L. floridana is considered lost ( Burton, 1963).

Type locality: Coast of Florida, USA .

Material examined: UFRJPOR 6726, Water Factory , Willemstadt, Curaçao (12°06′30.88″N, 68°57′13.53″W), 17.8 m depth, coll. E. Hajdu, 19 August 2011 . UFRJPOR 6757, Tug Boat , Caracasbaai, Curaçao (12°04′08.20″N, 68°51′44.40″W), 6.2 m depth, coll. B. Cóndor-Luján ,

23 August 2011. UFRJPOR 6765, Hook’s Hut , Caracasbaai, Curaçao (12°07′18.94″N, 68°58′11.46″W), 13.3 m depth, coll. E. Hajdu , 18 August 2011.

Colour: White to light blue in life ( Fig. 12A ) and greyish white to brown in ethanol ( Fig. 12B ).

Morphology and anatomy: This species has a massive growth form ( Fig. 12A ). The consistency is very rough and incompressible. The largest specimen (UFRJPOR 6726) measures 2.6 × 1.6 × 0.8 cm ( Fig. 12B ). The surface is ridged and hispid. The three analysed specimens had a single apical osculum (largest diameter = 0.5 cm). In the specimen UFRJPOR 6757, the osculum is particularly elongated and bears a very delicate margin. The atrial cavity is wide and hispid. The aquiferous system is leuconoid.

Skeleton: The skeleton is typical of the genus. It does not have special organization and it is composed of two size categories of triactines (I and II) and tetractines (I and II). The cortex and atrial wall are thin, whereas the choanosome is thick. Triactines II and tetractines II, which are the largest spicules, are found in the cortex and in the choanosome, tangentially positioned. Tetractines II are rare. Triactines I and tetractines I are spread in the choanosome and in the atrium. The apical actine of tetractines I penetrates the exhalant canals and the atrial cavity. Near the atrium, triactines I and tetractines I become sagittal.

Spicules: Triactines I. Regular. Actines are conical, straight, with blunt tips ( Fig. 12C ). Frequent. Sagittal triactines I were also observed. Size: 87.5–175.0/10.0– 22.5 µm. Triactines II. Regular. Actines are conical, straight, with blunt tips ( Fig.12D ). Highly variable size: 378.4–2378.4/54.1–389.2 µm. Tetractines I. Regular. Actines are slightly conical, straight, with blunt to sharp tips ( Fig. 12E ). The apical actine is smooth, thinner than the basal actines and has a sharp tip. Sagittal tetractines I were also observed. Size: 102.5– 200.0/11.2–20.0 µm (basal actine) and 25.0–50.0/7.5– 10 µm (apical actine). Tetractines II. Regular. Rare. Actines are conical, straight, with blunt tips ( Fig. 12F ). Highly variable size: 464.9–2162.2/108.1–270.3 µm.

Ecology: This species was found underneath boulders close to some incrusting and massive demosponges ( cf. Clathria ). No associated organisms were found on the surface of the analysed specimens. The analysed specimens from Curaçao were collected between 6 and 18 m depth; however, L. floridana has been reported down to 100 m depth in NE Brazil ( Lanna et al., 2009).

Geographical distribution: This species has a widespread distribution. Tropical Northwestern Atlantic Province – Floridian (Florida: Haeckel, 1872), Bermuda ( Bermudas: de Laubenfels, 1950), Greater Antilles ( Jamaica: Lehnert & Van Soest, 1998), Eastern Caribbean (La Martinique: Pérez et al., 2017) and Southern Caribbean (Urabá and San Andrés: Valderrama et al., 2009 and Curaçao: present study) ecoregions, North Brazil Shelf Province (Pará, Brazil: Borojevic & Peixinho, 1976) and Tropical Northwestern Atlantic Province – Northeastern Brazil, Eastern Brazil, Fernando de Noronha and Atol das Rocas ecoregions ( Borojevic & Peixinho, 1976; Lanna et al., 2009; Valderrama et al., 2009).

Molecular analysis: The ITS sequences of the specimens from Curaçao (UFRJPOR 6726 and UFRJPOR 6765) clustered within a monophyletic clade also composed of Brazilian (UFRJPOR 6480) and

Panamenian (PTL09-P100) specimens of L. floridana (pp = 1, b = 97, Fig. 4 ). The Curaçaoan specimens showed a higher molecular affinity with the Brazilian specimen (p distance = 0%) than with the Panamenian one, despite their geographic distance (p distance = 0.4%).

Taxonomic remarks: Our specimens match the original description of L. floridana provided by Haeckel (1872) as well as the redescription of Valderrama et al. (2009). Haeckel’s measurements are: triactines and tetractines I: 150.0–250.0/10.0–15.0 µm and triactines and tetractines II: 700.0–1500.0/100.0–150.0 µm.Those of Valderrama et al. (2009) are presented in Table 10. Leucetta floridana is not only one of the few species of Calcarea already reported from the Caribbean Sea, but it is also one of the most widespread species along the Western Tropical Atlantic.

SUBCLASS CALCARONEA BIDDER, 1898 ORDER LEUCOSOLENIDA HARTMAN, 1958 FAMILY AMPHORISCIDAE DENDY, 1893 GENUS LEUCILLA HAECKEL, 1872

Type species: Leucilla amphora Haeckel, 1872 .

Diagnosis: Amphoriscidae with sylleibid or leuconoid organization. The choanoskeleton is formed primarily by the apical actines of giant cortical tetractines and the unpaired actine of subatrial triactines or tetractines. It may contain dispersed spicules, but a typical articulated choanoskeleton is always absent ( Borojevic et al., 2002, emend.).

Figures

Figure 4. Bayesian phylogenetic tree inferred from the ITS sequences of the Calcinean species. Posterior probabilities and bootstrap values are given on the branches (pp/bootstrap). *Sequences generated in this study.

Figure 12. Leucetta floridana (UFRJPOR 6757). A, specimen in vivo. B, specimen after fixation. C, triactine I. D, triactine II. E, tetractine I. F, tetractine II.