Oceanapia bartschi ( De Laubenfels, 1934 )

Campos, Maurício, Mothes, Beatriz, Eckert, Rafael, Van, Rob W. M. & Soest, 2005, Haplosclerida (Porifera: Demospongiae) from the coast of Maranhão State, Brazil, Southwestern Atlantic, Zootaxa 963, pp. 1-22 : 11-13

Oceanapia bartschi ( De Laubenfels, 1934)

Figs. 7 A–F, Tab. III

Inflatella bartschi De Laubenfels, 1934: 21 ; Collette & Rützler, 1977: 309. Rhizochalina hondurasensis ( Carter, 1882) ; De Laubenfels, 1953: 524. Oceanapia bartschi ; Van Soest, 1980: 87, Fig. 32, pl. XIV, Fig. 1; Zea, 1987: 128, Fig. 39; Lehnert

& Van Soest, 1998: 94; 1999: 164.

Examined material. MCNPOR 3822, 3826, 13 m, 00°27’03”N – 45°34’85”W, 11.XI.1997 (MCNPOR 3822: fragment deposited in ZMAPOR 17910); MCNPOR 5337, 5346, 5348, 5359, 72 m, 00°22’N – 44°52’W, 18.VII.2001; MCNPOR 4762, 82 m, 00°20’50”N – 45°00’06”W, 09.VI.1999; MCNPOR 4765, 4767, 4772, 93 m, 00º11’13”N – 44º46’12”W, 10.VI.1999 (MCNPOR 4765: fragment deposited in ZMAPOR 17911); MCNPOR 3799, 64 m, 01°03’S – 43o31’W, 30.XI.1997; MCNPOR 3874, 80 m, 01°33’81”S – 43°15’87”W, 02.XII.1997 (fragment deposited in ZMAPOR 17912); MCNPOR 3820, 70 m, 01°57’01”S – 42°23’15”W, 05.XII.1997.

Material studied for comparison. Inflatella bartschi ( De Laubenfels, 1934) : material deposited in MCNPOR 2465 (det. Klaus Rützler). ZMA POR 3553 [MCNPOR 2642].

Description. Globular specimen ( Fig. 7 A): 12 cm diameter, 11 cm height (MCNPOR 5348). Smooth surface, detachable, bright and leathery. Two kinds of fistules: Smaller widespread on the surface, digitiform, thin and blind ends (3–6.5 cm long, 0.7–1 cm width). Inside these fistules there is a thin membrane, with a small central vent. A single larger central fistule, tube­shaped, very brittle, with ringed grooves (5.5 cm height, 2.5 cm width). Surface infested with Bryozoa. Preserved material with firm consistency in the surface, compressible internally, colour purple.

Skeleton. Ectosome with a dense and easily detachable crust ( Fig. 7 B). Thick layer of condensed spicules (300–800 µm thickness), sustained by multispicular thick tracts (100– 300 µm thickness), reaching the surface forming a network with meshes 100–220 µm in diameter. Choanosome with thick spicule tracts (40–170 µm thickness), forming polygonal or rounded meshes (400–900 µm diameter), filled in with loose spicules ( Fig. 7 C). Smaller fistules with a slender reticulation, many spicules arranged in multispicular sinuous tracts ( Fig. 7 D); between this tracts occur isolated spicules. Bigger fistule constituted by a network of multispicular tracts, forming rounded meshes; on the ringed region this mesh becomes denser ( Fig. 7 E).

Spicules. Strongyles ( Fig. 7 F): straight to slightly sinuous, symmetrical extremities. Measurements: 218.5–272.8–313.5 / 5.8–8.1–9.2 µm (MCNPOR 3822); 209– 268. 2 –304 / 4.6– 8. 1 –10.4 µm (MCNPOR 3826); 250– 267. 2 –290 / 3.8– 5 .4–7.5 µm (MCNPOR 5337); 230– 263. 9 –290 / 5– 9. 3 –12.5 µm (MCNPOR 5346); 200– 255 –280 / 5– 5. 8 –8.8 µm (MCN­ POR 5348); 240– 281. 4 –330 / 3.8– 5. 9 –7.5 µm (MCNPOR 5359); 199.5– 253. 5 –285 / 6.9– 9. 2 –12.7 µm (MCNPOR 4762); 220– 254. 4 –280 / 2.5– 8 –12.5 µm (MCNPOR 4765); 209– 264. 5 –313.5 / 4.6– 9. 1 –11.5 µm (MCNPOR 4767); 218.5– 266. 6 –294.5 / 4.6– 9. 2 –11.5 µm (MCNPOR 4772); 200– 257. 6 –290 / 5– 7. 8 –10 µm (MCNPOR 3874); 190– 298. 3 –361 / 6.9– 13. 2 –18.4 µm (MCNPOR 3820).

Remarks. The species Oceanapia bartschi is defined by the presence of strongyles in a wide size range. According to Zea (in litt.), the morphology of our samples matches with the Caribbean material, which also possesses some digitiform fistules when it lives in sanded substrata. Although the samples here do not possess the wide size range in the strongyles, we prefer to identify it with O. bartschi because of the additional characters. The present authors propose to emend the diagnosis of Oceanapia given by Desqueyroux­ Faúndez & Valentine (2002), with inclusion of the presence of strongyles in addition to that of oxeas.

Distribution. West Atlantic: Florida to Colombia (Van Soest, 1980; Lehnert & Van Soest, 1998; Zea, 1987). Brazilian coast: off the mouth of Amazon River ( Collette & Rützler, 1977); Maranhão State (present study).

Figures

FIGURE 7. Oceanapia bartschi (De Laubenfels, 1934). A, sample (scale: 5 cm). B, tangential view of ectosome (scale: 300 µm). C, perpendicular section of choanosome (scale: 300 µm). D, tangential view of smaller fistule (scale: 200 µm). E, tangential view of bigger fistule (scale: 200 µm). F, line drawings of strongyles (scale: 50 µm).