Eurypon verticillatum, Cavalcanti & Santos & Pinheiro, 2018

Cavalcanti, Thaynã, Santos, George Garcia & Pinheiro, Ulisses, 2018, Description of three species of Eurypon Gray, 1867 (Raspailiidae: Demospongiae: Porifera) from the Western Atlantic and a name to replace the the secondary homonym Eurypon topsenti, Zootaxa 4388 (1), pp. 89-101 : 95-98

Eurypon verticillatum sp. nov.

( Figures 1 , 6–7 , Table 1–2)

Type locality: Brazil, Pernambuco State, Goiana Municipality, Ponta de Pedras Beach.

Type specimens: Holotype. UFPEPOR 1966, Ponta de Pedras (07°37’00’’S – 34°48’51’’W), Goiana Municipality, Pernambuco State, Brazil, intertidal, coll. T. Cavalcanti and U. Pinheiro (30/VII/2015). Paratype. UFPEPOR 1967 and UFPEPOR 1968 (31/VIII/2015), UFPEPOR 1969 (29/IX/2015), collected at the type locality.

Diagnosis. Eurypon with blue color and long tylostyles (400–1100 / 2–9 µm), verticillate acanthostyles (I = 81–287 / 3–7 µm; II = 60–141 / 2–6 µm) and raphides (36–62 µm).

External morphology ( Fig. 6A–B ). Thinly encrusting sponge, covering surfaces up to 40 cm ² and 0.5–1.0 mm thick. Hispid surface and consistency firm but easy to tear. Oscula absent. Colour in life is blue which is kept when preserved (80% ethanol).

Skeleton ( Fig. 6C ). No special ectosomal skeleton. The choanosomal skeleton has a microcionid structure. The majority of tylostyles and acanthostyles are embedded in a dense spongin layer which protrude externally. Raphides are dispersed in the subectosomal region.

Spicules ( Fig. 7A–G ). Choanosomal tylostyles (460– 774.3 –1100 / 3– 5.7 –8 µm): elongated, smooth, curved, with hastate tips and rounded tyla ( Fig. 7A–B ); Acanthostyles I (121– 179.2 –236 / 3– 4.7 –6 µm): long, thin, straight to slightly curved, with few little spines on the shaft, concentrated on the base, and with subterminal tyla bearing bigger verticillate spines ( Fig. 7C–D ); Acanthostyles II (60– 80.4 –110 / 2– 4.2 –6 µm): straight, fusiform, with a flat base, abundant spines on the shaft, and with verticillate curved spines (hook-shaped) directed to the tips ( Fig. 7E– F ); Raphides (40– 49.9 –57 µm): small, smooth and abundant ( Fig. 7G ).

Distribution and ecology ( Fig. 1 ). Brazil: Northeastern Region: Pernambuco State: Goiana Municipality, intertidal zone. Eurypon verticillatum sp. nov. is abundant at ‘Ponta de Pedras’ reefs. All the sponges were found in an epibenthic association with bryozoan species. The bryozoans Amathia vidovici Heller,1867, Amathia sp. and Nolella stipata Gosse, 1855 were found over the new species surface ( Fig. 6A ).

Etymology. The specific epithet verticillatum refer to the verticillate spines next to base of acanthostyle I and II.

Remarks. Eurypon verticillatum sp. nov. is assigned to Eurypon for the possessing a spicule complement typical of the genus, composed by choanosomal tylostyles, echinating acanthostyles, raphides, a microcionid skeletal arrangement and encrusting habit. It differs from the Atlantic Ocean species of the genus for presenting exclusive verticillate acanthostyles. Additionally, it differs from others features. The species more similar to E. verticillatum sp. nov. is E. viride , which shares with the new species the presence of choanosomal tylostyles, raphides and acanthostyles. However, E. viride has only one category of typical acanthostyles, while the new species has two size classes of verticillate acanthostyles. Eurypon verticillatum sp. nov. is distinguished from E. lictor and E. topsenti for presenting acanthostyles. The new species differ from E. clavatella , E. clavatum , E. coronula , E. distyli , E. fulvum , E. lacazei , E. longispiculum , E. major , E. pulitzeri nom. nov., E. radiatum , E. toureti and E. viride , because these species have one category of acanthostyles while the new species has two categories of acanthostyles. The presence of choanossomal subtylostyles in combination with two categories of acanthostyles is found in E. clavilectuarium , E. hispidulum , E. incipiens , E. miniaceum , E. mucronale , E. scabiosum , E. simplex , E. suassunai and E. urizae . The new species differs from the latter species, by the choanosomal tylostyles and in spicules dimensions (Tab. 1). Eurypon verticillatum sp. nov. is distinguished from E. mixtum , which has the spicules components of tylostyles, acanthostyles I, II, and ectosomal styles or subtylostyles. The new species differ from E. mixtum in presenting raphides and in spicules dimensions (Tab. 1). Finally, it is distinguished from E. oxychaetum sp. nov. and E. potiguaris sp. nov. by their spicules complement and dimensions (Tab. 1).

TABLE]. Comparative micrometric đata on the spicules, shape anđ đistribution overview of the new Eurypon species from the Atlantic Ocean. Values are in micrometers (µm), expresseđ as follows: minimum̅maximum or minimum̅ mean ̅maximum length/wiđth. References are numbeređ in parentheses anđ listeđ after the table.

……continued on the next page TABLE]. (Continueđ) References: (1) Pulitzer-Finali (1983); (2) Topsent (1936); (3) Little (1963); (4) Boury-Esnault et al. (1994); (5) Santos et al. (2014); (6) Boury-Esnault & Lopes (1985); (7) Lévi (1969); (8) Topsent

1904); (9) Topsent (1928); (10) Carter (1876); (11) Sarả & Siribelli (1960); (12) Pulitzer-Finali (1978); (13) Uriz (1988); (14) Bowerbank, 1866; (15) Topsent (1927); (16) Bowerbank (1874); (17)

Burton (1954); (18) Topsent (1894); (19) Topsent (1889).

Figures

FIGURE 1. Location of study area and collection sites of Eurypon species, (1) Eurypon verticillatum sp. nov. (Pernambuco State); (2) (3) Eurypon oxychaetum sp. nov. (Paraíba State); (4) Eurypon potiguaris sp. nov. (Rio Grande do Norte State). Abbreviations are:AL = Alagoas State; BA = Bahia State; CE = Ceará State; PB = Paraíba State; PE = Pernambuco State; RN = Rio Grande do Norte State.

FIGURE 7. Spicule complement of Eurypon verticillatum sp. nov. (UFPEPOR 1966, holotype) in SEM. A, choanosomal tylostyles; B, tylostyles details;C, size variation ofacanthostyles I; D, acanthostyles I and details of verticillate spines (arrows); E, size variation of acanthostyles II; F, acanthostylesIIdetails and detailsof verticillate spines (arrows); G,raphides.Scale bars: A = 200 µm; B, D = 10 µm; C = 50 µm; E = 20 µm; F–G = 5 µm.

FIGURE6. Eurypon verticillatum sp. nov. (UFPEPOR 1966,holotype).A, specimen invivo; B, close up of sponge surface; C, thick section showing ectosome and choanosome.Scale bars:A = 2cm; B = 5 mm; C = 700 µm.