FIGURE 1. Location map (1.1) of the Plio-Pleistocene echinoid-bearing deposits cited in the text and simplified geo-structural sketch (1.2) of NE Sicily (from Antonioli et al., 2006 and Arisco et al., 2006, modified). Capo Milazzo sites: 1, Punta Lazzi; 2, Cala S. Antonio; 3-4, Lighthouse area; 5, Punta Mazza; 6, Bacedasco (Piacenza) and Salsomaggiore (Parma); 7, Quattro Castella and Castellarano (Reggio Emilia); 8, Cianca and Fossetta (Modena); 9, Vescona quarry near Asciano (Siena); 10, Chiusi (Arezzo); 11, Anzio (Rome); 12, Ponte Calderaro and Monte Torre (Catanzaro); 13, Lazzaro and Croce Valanidi (Reggio Calabria); 14, Salice, Coilare and Contrada Petrazza (Messina); 15, Ficarazzi (Palermo).
FIGURE 2. Simplified evolution of the Punta Mazza section (Capo Milazzo, NE Sicily, Italy) with stratigraphy by means of calcareous nannofossils (this study) and Violanti (1988).
FIGURE 3. The Punta Mazza section at Capo Milazzo (NE Sicily, Italy). MM, late Miocene Megabreccias; PP, Pliocene-Early Pleistocene (Gelasian) marls, following Violanti (1988); PC, Pleistocene, Calabrian; PI, Pleistocene, Ionian; PT, Late Pleistocene (Tyrrhenian) conglomerate; PTVS, post Tyrrhenian volcaniclastic deposit and soil.
FIGURE 4. Species of the genus Cidaris Leske, 1778 from the Plio-Pleistocene of Capo Milazzo (4.1-7, 4.10-16, 4.19, 4.24, 4.27-28, 4.30-32) and Italy mainland (4.17-18, 4.20-23, 4.25-26, 4.29), and from the Recent site off Gallipoli, Ionian Sea (4.8-9). Cidaris margaritifera (Meneghini, 1862) from the uppermost Piacenzian-Gelasian and Calabrian of Capo Milazzo. 4.1, lateral view of a complete segment (MG.1033.39) with only the first fully developed adapical tubercles bearing crenulation, W=13 mm; Cala S. Antonio; 4.2, oblique view of a complete segment (MG.1033.41) with only the two last adoral plates confluent; W=25 mm, Punta Lazzi; 4.3, complete, fusiform spine (MG.1035.31) with almost smooth ridges, L=43 mm, Punta Lazzi; 4.4, complete, fusiform, non-crenulate spine (MG.1035.32) with fine spinules, L=52 mm, S. Antonio; 4.5, non-crenulate spine (MG.1032.68) with small granules, L=22 mm, Punta Lazzi; 4.6, cylindrical spine (MG.1032.69) with almost smooth ridges, L=24 mm, S. Antonio; 4.7, cylindrical spine (MG.1035.33) with low ridges bearing fine spinules; base partially crenulate, L=50 mm, S. Antonio; 4.10, close up of a spine (MG.1032.53) with smooth ridges, Ds=1.7 mm, S. Antonio; 4.11, close up of a spine (MG.1032.54) with low and sharp spinules, Ds=2.4 mm, S. Antonio; 4.12, spine (MG.1032.55) with granules, Ds=2.5 mm, S. Antonio; 4.13, crenulate spine (MG.1032.57) with ridges bearing small granules, Ds=4.2 mm, S. Antonio; 4.14, spine (MG.1032.58) with prominent spinules, Ds=4.8 mm, S. Antonio; 4.15, spine (MG.1032.62) with low spinules and space between rows covered by spongy coat, and close up view (4.16) of the non-crenulate acetabulum rim, Ds=4.8 mm, S. Antonio; 4.19 , close up view of a poriferous area (MG.1032.06), Punta Lazzi; 4.24, section of a primary spine (MG.1032.38), Ds=4.6 mm, Punta Lazzi; 4.27, fusiform, partially crenulate spine (MG1032.51) with spongy coat still visible between ridges; Ds=5.8 mm, Punta Lazzi; 4.28, short and stout primary spine (MG.1033.38); L=17 mm, Punta Lazzi. Cidaris cidaris (Linnaeus, 1778), complete test, D=42 mm (MG.1033.36); Recent, Gallipoli (Puglia), depth: 55 m. 4.8, adoral view; 4.9, close up of a crenulate adapical tubercle. Cidaris margaritifera (Meneghini, 1862) from Italy mainland. 4.17, frontal view of a complete segment, H=46 mm, Tmax=4 mm at ambitus (MG.1032.01), Calabrian of Lazzaro (Reggio Calabria), 4.18, lateral view; 4.20, primary spine; Ds=3.9 mm; Pliocene, Fossetta (Modena), Landi collection (IPUM); 4.21 , primary spine with rounded grains, Ds= 4.2 mm, Pliocene, Cianca (Modena), Landi collection (IPUM), and close up view of the smooth acetabulum rim (4.22) ; 4.23, close up of a spine with prominent spinules, Ds=4.3 mm (MG.1078.02), Piacenzian, Quattro Castella (Reggio Emilia); 4.25, primary spine with thorns and close up view of the partially crenulate acetabulum (4.26), Ds=3.7 mm (MG.1034.04), early Pliocene, Vescona quarry near Asciano (Siena); 4.29, interambulacral plate, W=14.8 mm, T=4 mm (MG.1034.05), early Pliocene, Chiusi (Arezzo), with lateral view (4.30). Cidaris cerullii (Checchia Rispoli, 1923), (MG.1033.34), Gelasian of Punta Lazzi. 4.31, test fragment, H=36 mm; with 4.32, close up of the ambulacral area. Scale bars equal 2 mm.
FIGURE 5. Plio-Pleistocene species of the genus Histocidaris Mortensen, 1903 from Capo Milazzo (5.1-3, 5.6-13, 5.16) and from Italy mainland (5.4-5, 5.14-15). Histocidaris sicula Borghi, 1999; uppermost Piacenzian-Gelasian of Cala S. Antonio. 5.1, holotype (MG.1073), W=27 mm; 5.2, interambulacral plate with the adjoining ambulacral plates, (MG.1033.42), W=12 mm; 5.3, cross section of a primary spine (MG.1033.06), Ds=2.6 mm; 5.6, close up view of the hollow tip of a primary spine (MG.1033.33), Ds=2.7 mm; 5.7, primary spine (MG.1035.08) with smooth shaft, the arrow marks the edge of the collar, 2 mm long, Ds=2.5 mm; 5.8, primary spine (MG.1074) with low ridges and crenulate acetabulum rim (5.9), the arrow marks the edge of the collar, which is 5.8 mm long, Ds=2.8 mm; 5.10 , adoral primary spine (MG.1033.09), L=12 mm; 5.11, adoral primary spine (MG.1077), L=11 mm, with lateral view (5.12); 5.13 , complete primary spine (MG.1035.01), L=128 mm; 5.16, adapical interambulacral plates (MG.1033.32), W=22 mm. Histocidaris rosaria (Bronn, 1831). 5.4, primary spine with sharp spinules (MG.1034.02), Ds=3 mm, Piacenzian, Campore quarry, Salsomaggiore (Parma); 5.5, primary spine with prominent thorns (MG.1034.03), Ds=4 mm, Piacenzian, Campore quarry, Salsomaggiore; 5.14, thorny adoral primary spine (MG.1034.04), L=14 mm, Piacenzian, Campore quarry, Salsomaggiore; 5.15 , tip of a primary spine, Ds=2.5 mm (MG.1034.01), early Pliocene, Vescona quarry, Asciano (Siena). Scale bars equal 2 mm.
FIGURE 6. Stirechinus scillae Desor, 1856 from the Plio-Pleistocene of Sicily. 6.1-3, complete test (MG.1034.10), D=33.5 mm, Early Pleistocene of Contrada Coilare (Messina), showing apical (6.1), lateral (6.2) and oral (6.3) views. 6.4, close up of the ridges linking the primary tubercles (MG.1034.18); 6.5, close up view of a pore-zone (MG.1034.19); 6.6-7, primary spines, L=20 mm (MG.1086.01-02); 6.8, close up view of an interambulacral scrobiculate primary tubercle, lacking ridges. All from the very late Piacenzian-Gelasian of Punta Lazzi. 6.9-10, apical (6.9) and lateral (6.10) views of a complete juvenile test (MG.1035.22), D=6.4 mm, very late Piacenzian-Gelasian of Punta Mazza; 6.11, lateral view of a complete corona, D=54 mm (MG.1034.18), very late Piacenzian-Gelasian of Punta Lazzi; 6.12, scheme of the apical system taken from a specimen of the Checchia Rispoli collection (MGUP); figured in Checchia Rispoli, 1916, plate 27, figure 6. Scale bars equal 2 mm.
FIGURE 7. Spatangoid species from the Pliocene of north Italy. 7.1, aboral view of Schizaster braidensis Botto Micca, 1896, L=29 mm (Dip.Te.Ris IV.G60), Zanclean-Piacenzian of Genova. 7.2-3, aboral view of Holanthus ovatus (Sismonda, 1842), Pliocene of San Ruffino (Reggio Emilia), with the enlarged scheme of the plating structure (7.2) from a compete test, L=21 mm, MG.1034.06 (7.3). Scale bar equals 1 cm.
