Key to Schizoretepora species from the Atlanto-Mediterranean region

1. With spiramen ................................................................................................................................... 2

– Without spiramen .............................................................................................................................. 4

2. Branches uniseriate; giant frontal avicularia projecting perpendicular to the sides, longer than the branch width ................................................................................................... dentata (Calvet, 1931)

– Branches bi- or pluriseriate; frontal avicularia shorter than the branch width .................................. 3

3. Branches bi- or triseriate; distal ends of the large bilobated peristome converging to form a large circular spiramen ............................................................................................ calveti d’Hondt, 1975 .

– Branches quadri- or pluriseriate; distal ends of the large bilobated peristome converging to form a drop-shaped spiramen .................................................................................. solanderia (Risso, 1826)

4. Erect vinculariform (or reteporiform) colonies ................................................................................ 5

– Erect laminate colonies.......................................................................... serratimargo (Hincks, 1886)

5. Without frontal adventitious avicularia ............................................................................................ 6

– With frontal adventitious avicularia .................................................................................................. 7

6. Abfrontal slightly rugose but not tuberculate; frontal slightly rugose (not tuberculate), with low number of pores (2–4); zooids longer (average AzL> 470 mm; min AzL: 320 mm) ........................ .......................................................................................................................... imperati (Busk, 1884)

– Abfrontal strongly rugose, tuberculate; frontal tuberculate, with higher number of pores (2–5); zooids shorter (average AzL <350 mm; max AzW: 450 mm) ........................................................... .................................................. sp. nov.? (= S. imperati sensu O’Donoghue & de Watteville 1939)

7. Frontal adventitious avicularia of two types (oval and almond-like); frontal slightly rugose, with few areolae (2–3); abfrontal smooth or slightly rugose, with adventitious oval avicularia and rare triangular avicularia ........................................................................ pungens (Canu & Bassler, 1925)

– Frontal adventitious avicularia only almond-like with acute end; frontal rugose or nodular, with larger number of areolae (4–5); abfrontal rugose, with abundant triangular adventitious avicularia but lacking oval adventitious avicularia ........................................................................................... 8

8. Colonies always fenestrate (reteporiform); with large number of abfrontal wide triangular adventitious avicularia; zooids narrower (average AzW <260 mm; max AzL: 380 mm) ...................................... ..................................................................................................... aviculifera (Canu & Bassler, 1930)

– Colonies branched, but poorly fenestrated (vinculariform); with few sparse thin abfrontal triangular avicularia; zooids wider (average AzW> 330 mm; min AzL: 240 mm .............................................. ........................................................................................... hassi Harmelin, Bitar & Zibrowius, 2007