Pione mazatlanensis, (HANCOCK, 1867)

Carballo, José Luis, Cruz-Barraza, José Antonio & Gómez, Patricia, 2004, Taxonomy and description of clionaid sponges (Hadromerida, Clionaidae) from the Pacific Ocean of Mexico, Zoological Journal of the Linnean Society 141 (3), pp. 353-397 : 382-383

PIONE MAZATLANENSIS ( HANCOCK, 1867) ( FIG. 20 )

Synonymy: Cliona mazatlanensis Hancock, 1867: 240 .

Material examined: MNCN-1.01/307, Sta. Cruz Ensenada del Pabellon (Culiacán, Sinaloa), 22∞7¢33¢¢N-107∞18¢37¢¢W, 3 m depth, 06.vii.2002, boring into a bivalve shell ( Veneridae ). LEB-ICML- UNAM-278, Isla del Peruano (Bahía de Guaymas, Sonora), 27∞54¢35¢¢N-110∞58¢17¢¢W, 15 m depth, 03.xi.2000, boring into a bivalve shell ( Pinctada mazatlanica ). LEB-ICML-UNAM-370, Punta Chile (Mazatlán, Sinaloa), 23∞12¢29¢¢N-106∞25¢40¢¢W, 1.5 m depth, 08.viii.2001, boring into a bivalve shell ( Crassostrea sp. ). LEB-ICML-UNAM-372, Los Arcos (Puerto Vallarta, Jalisco), 20∞32¢73¢¢N-105∞18¢47¢W, 1 m depth, 23.i.2001, boring into a serpulid polychaete. LEB- ICML-UNAM-378, Isla Pájaros (Mazatlán, Sinaloa), 23∞15¢29¢¢N-106∞28¢25¢¢W, 4 m depth, 18.x.2001, boring into a serpulid polychaete. LEB-ICML-UNAM- 395, Punta Santiago (Manzanillo, Colima), 19∞5¢41¢¢N-104∞25¢22¢¢ W 1.5 m, depth 16.xi.2001, boring into a bivalve shell ( Crassostrea sp. ). LEB-ICML- UNAM-553, Sta. Cruz Ensenada del Pabellón (Culiacán, Sinaloa), 22∞7¢33¢¢N-107∞18¢37¢¢W, 3 m depth, 06.vii.2002, boring into a bivalve shell ( Veneridae ). LEB-ICML-UNAM-477, Antiguo Corral del Risco (Punta de Mita, Nayarit), 20∞46¢20¢¢N-105∞32¢49¢¢W, 2 m depth, 11.vi.2003, boring into dead coral.

Description: Specimens always growing in alpha stage, covering a maximum surface diameter of 12.5 cm. The species has very small circular papillae (0.1–1.4 mm in diameter) that are level with the surface of the substratum ( Fig. 12B ). They are from 0.1 to 2.9 mm apart and very evenly scattered on the surface. Fusion of papillae has not been observed. Oscules are also very small; ranging from 0.1 mm to 0.8 mm in diameter (average 0.41 mm). The colour is red when alive and light red in alcohol.

Skeletal characters: There are three types of spicules: straight tylostyles which are gradually tapering to a sharp point, with heads mainly spherical or oval, although terminal knobs have been observed ( Fig. 20A ); they measure 202 ¥ 4.2 Mm on average (6.3 Mm head width); acanthoxea with minute spines over the entire surface, which are bent at the centre and with both ends sharply pointed (average 86 ¥ 4 Mm) ( Fig. 20B ); and microrhabds densely covered by robust spines, with 2–4 bends, and mostly with rounded ends (average 10.8 Mm) ( Fig. 20C, D ). The microrhabds can be straight, curved, or ‘S’-shaped ( Table 10) ( Fig. 20C ).

Distribution: de Laubenfels (1954) described a similar red specimen of C. vastifica . Perhaps some registers of P. vastifica from the Pacific Ocean may be considered as P. mazatlanensis . Mexican Pacific Ocean: Sonora, Sinaloa and Colima.

Remarks: The species Cliona mazatlanensis was synonymized with C. vastifica by Topsent (1891); without providing important arguments for that decision. Rützler & Stone (1986) comment about the great difficulty that exists in the Cliona vastifica complex (specimens containing three spicule types: tylostyles, microspined oxeas, and microspined microrhabds), due to the great variability among all types. In many cases this has led others to synonymize species with these three types of spicules with C. vastifica without a clear justification. One of the most important features that easily distinguishes P. mazatlanensis from P. vastifica is the small size of its papillae, and its red colour in life. The typical P. vastifica from the Mediterranean and West Atlantic coasts has characteristically bigger papillae, and a different orange or bright orange colour ( Carballo et al., 1994; Carballo, 1994; Rosell & Uriz, 2002; among others). Moreover, the size of the microrhabds is another distinguishing feature, longer on average in the Mediterranean and Atlantic coast specimens (19 Mm in Rützler, 1973; 23 Mm in Old, 1941; 25 Mm in Rosell, 1994). We think that P. mazatlanensis has important characteristics such as colour and papillae size to maintain it as a valid and different species from Pione vastifica .

Figures

Figure 12. External morphology of A, Cliona amplicavata. The arrow shows an oscule. B, Pione mazatlanensis boring into different calcareous material. C, Cliona vermifera boring into the coral Pavona gigantea. The papillae are only visible in the base of the coral. D, Excavating pattern of the papillae can be observed after breaking a fragment of the coral. E, Spheciospongia incrustans sp. nov. at 5 m depth; the arrow shows an oscule. F, Spheciospongia incrustans sp. nov.; the arrows show the pore sieves.

Figure 20. Pione mazatlanensis: A, heads and tip of the tylostyles; B, acanthoxeas; C, microrhabds; D, detail of the spines.