Raspailiidae (Porifera: Demospongiae: Axinellida) from the Mexican Pacific Ocean with the description of seven new species Author Aguilar-Camacho, Jose Maria Author Carballo, Jose Luis text Journal of Natural History 2013 J. Nat. Hist. 2013-05-01 47 25 - 28 1663 1706 http://dx.doi.org/10.1080/00222933.2013.769642 journal article 10.1080/00222933.2013.769642 1464-5262 4607504 74DE7552-F218-48AF-89E2-2EB24465404F Eurypon tylospinosum sp. nov. ( Figures 14B , 17 , 18 ) Material examined Holotype : MCNM 1.01 / 659, 27 / 11 / 2002 , Cabo Haro , ( Guaymas , Sonora ) 15 m (27 ◦ 52 ′ 5 ′′ N, 110 ◦ 57 ′ 1 ′′ W) . Paratype : 769-LEB-ICML-UNAM, 27 / 11 / 2002 , Cabo Haro , ( Guaymas , Sonora ), 15 m (27 ◦ 52 ′ 5 ′′ N, 110 ◦ 57 ′ 1 ′′ W). Description Encrusting sponge, size 2–5 cm length × 1–2 cm width and 3–5 mm thick. Oscules and ostia not visible. Surface smooth. Consistency flexible and difficult to tear. Colour in life red, pale in preservation ( Figure 14B ). Skeleton Choanosomal subtylostyles with a pronounced head or modified to style: 200–575 × 7.5–15 µm ( Figures 17A , 18A ). Acanthostyles with swollen head with prominent spines. These spines are arranged as a crown around the head: 70–200 × 2.5–7.5 µm ( Figures 17B, C , 18B ). Straight or curved subectosomal styles / anisoxeas: 330–460 × 1.75–2.5 µm ( Figures 17D , 18C ) ( Table 9 ). The ectosomal skeleton is absent. The choanosomal skeleton has a hymedesmoid structure. Main subtylostyles and acanthostyles are embedded in a spongin layer ( 10–25 µm thick). The styles / anisoxeas are dispersed in trichodragmas in the subectosomal region ( Figure 18D ). Figure 17. Eurypon tylospinosum sp. nov. Scanning electron microscopy images of spicules. (A) Choanosomal tylostyles; (B) acanthostyle with swollen head I; (C) acanthostyle with swollen head II; (D) subectosomal style. Scale bars: 50 µm (A), 10 µm (B), 20 µm (C), 100 µm (D). Remarks Eurypon tylospinosum sp. nov. is a subtidal species distributed from the Gulf of California. It is characterized by having acanthostyles with swollen head and with prominent spines, which are arranged as a crown around the head. The only species described worldwide that have these features are E. simplex ( Bowerbank 1874 ) and E. coronula ( Bowerbank 1874 ) ( Table 12 ). Eurypon simplex ( Bowerbank 1874 ) is a yellow encrusting sponge described from the Shetland Islands . It has tylostyles (2116 × 27.1 µm ) and acanthostyles (105.8–218.9 × 8.4 µm ). The tylostyles are shorter in E. tylospinosum sp. nov. than in E. simplex . Besides, E. tylospinosum sp. nov. has subectosomal styles which are lacking in E. simplex . Eurypon coronula ( Bowerbank 1874 ) is a grey encrusting sponge recorded from the Shetland Islands . It has tylostyles ( 635–1411 µm ) and acanthostyles ( 254 µm ). The tylostyles are longer in E. coronula than in E. tylospinosum sp. nov. The remaining species assigned to the genus Eurypon have spicules in a different category or length than E. tylospinosum sp. nov. ( Table 12 ). Figure 18. Drawings of Eurypon tylospinosum sp. nov. (A) Choanosomal tylostyles / styles; (B) acanthostyles recurved by prominent spines (two categories); (C) subectosomal styless / anisoxeas; (D) choanosomal skeleton (hymedesmoid). Scale bars: 40 µm (A–C), 75 µm (D). Table 9. Spicule measurements of Eurypon tylospinosum sp. nov. in µm.

Material	Choanosomal subtylostyles	Acanthostyles	Subectosomal
examined	(Length × Width)	(Length × Width)	styles / anisoxeas
(Length × Width)
MCNM	230-(445.6)-550 × 7.5-(11.8)-15	65-(125.5)-195 ×	300-(380.1)-450 ×
1.01 / 659	2.5-(4.9)-7.5	1.75-(2.4)-2.5
LEB-769	200-(470.5)-575× 7.5-(12.6)-15	70-(130.2)-200 ×	330-(397.2)-460 ×
2.5-(5.8)-7.5	1.75-(2.3)-2.5

Etymology Named tylospinosum by the swollen and spiny head of the acanthostyles.