Porifera, one new species Suberea purpureaflava n. sp. (Demospongiae, Verongida, Aplysinellidae) from northern Red Sea coral reefs, with short descriptions of Red Sea Verongida and known Suberea species Author Gugel, Jochen Author Wagler, Marit Author Brümmer, Franz text Zootaxa 2011 2994 60 68 journal article 10.5281/zenodo.278410 bb8dd26a-ed3e-4f3b-bcdf-1bf44432de70 1175-5326 278410 Suberea purpureaflava n. sp. ( Figs. 2 A, B; 3A, B; Tab. 1 , 2 , 3 ) Material examined. All specimens were collected by MW. Holotype ( SMF 10700), collected 30 April 2008 in Dahab (“Lighthouse”) at 28°29' 54.1" N , 34°31' 16.2" E , at a depth of 19 m . Paratype material. Paratype I ( SMF 10701), collected 19 November 2008 in Dahab (“Lighthouse”) at 28°29' 54.2" N , 34°31' 16.0" E , at a depth of 18 m . Paratype II ( ZMTAU PO 25474), collected 19 November 2008 in Dahab (“Lighthouse”) at 28°29.892’N , 34°24.262’ E , at a depth of 20 m . External morphology. The holotype , which is the free end of a branch, is 3–3.5 cm in length, 1–1.5 cm in height and about 2–2.5 cm in width ( in situ Fig. 2 A, Fig 3 A), whereas the paratypes are part of the free ends of a thick crust, both 2 x 2 x 2 cm in diameter and growing vertically. The sponge is thickly encrusting with a few free branches depending on its growth stage. The ectosome builds a rubber-like outer region, about 1–2 mm thick and is in parts removable. This strongly collagenous cortex-like region also shows a dark violet colour (fixed), in life it is dark red. The choanosome is brightly yellow in life and slightly more brittle than the ectosome above it. When the choanosome is fixed, it darkens quickly to dark violet. Freshly prepared but fixed specimens still show the clear distinction between choanosome and ectosome. The consistency of the sponge is tough, but elastic and fairly easy to tear. The surface is strongly conulose in the fixed state ( Fig. 3 A, not so much in situ ; but this might be due to different states of contractions). The conules appear every 0.5 cm with a diameter of about 2.5 mm , the height of the single conules is ca. 1.5 mm and they are moderately pointed with no ridges between them. Ostia are only present between the conules (in depressions), which corresponds with the conspicuous whitish pore sieves in situ ( Fig. 2 B), the numerous ostia are approximately 6 5–100 x 35 –50 µm in diameter. The outer surface of preserved specimens resembles that of preserved Suberea creba specimens as indicated in Bergquist & Cook (2002a) and that of preserved specimens of Suberea mollis in Row (1911) . Only a few oscules can be seen in the preserved holotype as round holes with a diameter of about 1.5–3 mm . In situ the oscules (diameter here 2–8 mm ) are visible as light yellow dots ( Fig. 2 ), with the yellow choanosome seen from outside. Many canals of variable thickness occur within the outer layer of the choanosome. Colour in life (the ectosome) dark red ( Fig. 2 ) with whitish pore sieves at lower parts of the surface ( Fig. 2 B); dark violet in ethanol ( Fig. 3 A). Skeleton. The dendritic fibres are 110–142–170 µm in diameter being either round or oval in cross-section ( Tab 1 for specimen comparisons), with pith 80–102–125 µm thick and bark 16–18–20 µm. Sometimes the bark consists of several irregular layers (see Bergquist & Cook 2002a ), but in the present species it is not as irregular as in the type species. Bark 9.4–16.9 % of the whole fibre, pith 83.1–90.6 % ( Tab. 1 ).. Each conule consists of the termination of an ascending fibre, slightly pushing the surface membrane. Foreign material could not be detected. The fibres look sometimes rather irregular ( Fig. 3 B) and are quite rare. TABLE 1. Measurements on fibres of different specimens.

Specimen	Whole fibre	Pith	Bark	Occupation of the pith (%)
Holotype (SMF 10700)	110–142–170 µm	80–102–125 µm	16–18–20 µm	72 %
Paratype I (n=8, SMF 10701) Paratype II (ZMTAU PO 25474)	80–112–153 µm 85–122–160 µm	75–96–113 µm 70–84–115 µm	7.5–12–15 µm 10–21–27 µm	86 % 69 %

FIGURE 2. Suberea purpureaflava n. sp. in life, A) The holotype growing on vertical substrate, B) Detail of the pore fields in another specimen, and one oscule as a yellow dot. Scale bars 5 cm. FIGURE 3. Suberea purpureaflava n. sp. A) preserved holotype, scale bar 1 cm, B) rather irregular holotype: fibre with clearly visible bark (arrow), scale bar 200 µm. Ecology. The holotype was collected on hard substratum (coral rubble). The specimen co-existed with species such as Paraleucilla cf. crosslandi (Porifera, Calcarea), Dendrophillidae sp. (Cnidaria, Hexacorallia, Scleractinia), Comatella cf. maculata (Echinodermata, Crinoidea) and an undetermined colonial ascidian (Tunicata, Ascidiacea). Other specimens grew mostly on vertical hard substratum, frequently beneath overhangs. Specimens were observed between 10 and 20 m depth. The species was neither extremely rare nor very abundant, a correlation of its occurrence to obvious ecological conditions (like e.g. currents, nutrition or symbionts) could not be seen. Etymology. The species is named after the dark red or purple colour of large parts of the ectosome of living specimens (lat. purpureus = red, purple, brilliant) and their bright yellow choanosome (lat. flavus = yellow) visible through the oscules in life.