Pleurocora arachnoides ( Knorr & Walch, 1777 )

Baron-Szabo, Rosemarie C., 2008, Dendrophylliina, Caryophylliina, Fungiina, Microsolenina, and Stylinina, Zootaxa 1952, pp. 1-244 : 115-116

Pleurocora arachnoides ( Knorr & Walch, 1777)

Pl. 9, Fig. 4

v*1777 Astroites arachnoides: Knorr & Walch , vol. 3, p. 193, pl. 6e, fig. 6 (topotypes studied).

1778 Astroites arachnoides: Schröter , vol. 3, p. 461, pl. 9, fig. 3.

1799 Madrepores: Faujas-Saint-Fond, pl. 41, fig. 6.

v1826 Astraea arachnoides: Goldfuss , vol. 1, p. 70, pl. 23, figs 9a–c (topotypes studied).

v1846 Lithodendron gemmans N. Michelin , p. 305, pl. 72, fig. 6.

v1848d Pleurocora gemmans: Milne Edwards & Haime , p. 310.

v1848 d Pleurocora alternans: Milne Edwards & Haime , p. 312.

v1848 d Pleurocora Koninckii: Milne Edwards & Haime , p. 312 (topotypes studied)

1850 Phyllocoenia arachnoides: d’Orbigny , vol. 2, p. 277.

v1851 a Astraea Riemsdycki: Milne Edwards & Haime , p. 98.

v1857 Heliastraea Riemsdycki: Milne Edwards , vol. 2, p. 469.

v1857 Pleurocora alternans: Milne Edwards , vol. 2, p. 603.

1857 Pleurocora Koninckii: Milne Edwards , vol. 2, p. 603.

1881 Astraea arachnoides Goldfuss : Quenstedt, p. 855, pl. 176, fig. 50.

1903a Haplohelia ornata nov. sp.: Felix, p. 323, pl. 17, figs 14–15.

1903a Oculina ogilviae nov. sp.: Felix, p. 323, pl. 23, figs 4, 5.

1906 Pleurocora Angelisi n. sp.: Felix, p. 47, pl. 3, figs 2–2b.

1914 Orbicella Riemsdycki E. H. sp. 1851 : Felix, pars 7, p. 167.

1914 Pleurocora alternans E. H. 1849: Felix, pars 7, p. 171.

1914 Pleurocora Angelisi Felix 1906 : Felix, pars. 7, p. 171.

1914 Pleurocora gemmans Michelin sp. 1847: Felix, pars 7, p. 171.

1914 Pleurocora Koninckii E. H. 1849 : Felix, pars 7, p. 172.

1914 Haplohelia ornata Felix 1903 .: Felix, pars 7, p. 233.

v1925 Orbicella Riemsdijcki var. conica (nov. var.): Umbgrove, p. 103, pl. 8, fig. 3.

1987 Haplohelia regularis, D’Orbigny : Meyer, pl. 5, figs 8–9.

(v)?1991 “Branching coral”: Bryan, p. 430, Fig. 7C.

v1997 Pleurocora cf. alternans Milne-Edwards & Haime, 1849 : Baron-Szabo, p. 77, pl. 10, figs 4, 6.

v1998 Latohelia cicularia n. sp.: Baron-Szabo, p. 150, pl. 9, figs 1–4, pl. 10, fig. 2.

nonv1999 Pleurocora cf. alternans Milne Edwards & Haime, 1849 : Baron-Szabo, p. 455, pl. 3, fig. 2.

v1999 Latohelia cf. cicularia Baron-Szabo, 1998 : Baron-Szabo, p. 461, pl. 5, fig. 3.

1999 Montastrea arachnoides: Leloux , p. 193, fig. 2.

2000 Heliastraea riemsdycki (Milne-Edwards & Haime 1851) : Löser, p. 40.

2000 Latohelia cicularia, Baron-Szabo 1998 : Löser, p. 46.

2000 Montastraea arachnoides ( Knorr & Walch 1777) : Löser, p. 53.

2000 Orbicella riemsdijcki var. conica, Umbgrove 1926 : Löser, p. 57.

2000 Pleurocora alternans, Milne-Edwards & Haime 1849 : Löser, p. 66.

2000 Pleurocora angelisi, Felix 1906 : Löser, p. 66.

2000 Pleurocora gemmans ( Michelin 1847) : Löser, p. 66.

2000 Pleurocora konincki, Milne-Edwards & Haime : Löser, p. 66.

2002 ‘solitary coral’: Bauer et al., pl. 4, fig. 9.

2002 Pleurocora alternans Milne Edwards & Haime, 1849 : Baron-Szabo, p. 106.

2002 Pleurocora angelisi Felix, 1906 : Baron-Szabo, p. 106.

2002 Pleurocora cicularia ( Baron-Szabo, 1998) : Baron-Szabo, p. 106.

v2002 Pleurocora gemmans ( Michelin, 1846) : Baron-Szabo, p. 105, pl. 73, figs 2–3, 5, 8–9, pl. 74, figs 1–4, 6. 2002 Pleurocora ornata (Felix 1903) : Baron-Szabo, p. 106.

2002 Haplohelia ogilviae (Felix 1903) : Löser et al, p. 328 (older synonmys cited therein).

2002 Haplohelia ornata, Felix 1903 : Löser et al, p. 328 (older synonmys cited therein).

v2002 Montastrea arachnoides conica ( Umbgrove, 1925) : Leloux, p. 22.

v2004 Pleurocora gemmans (Michelin) : Moosleitner, p. 180, pl. 78, figs 6, 12, 13.

Dimensions. d=2–3.5 mm, juvenile around 1.5 mm; c-c: 3–5 mm (in submassive colonies); s=24–48.

Description. Submassive, plocoid to subdendroid colony; costosepta arranged in 3 to 4 complete cycles, depending on ontogenetical stage of corallite; columella spongy-papillose, generally well-developed.

Remarks. Re-examination of type and original material revealed that the species Pleurocora gemmans (Michelin) , P. alternans Milne Edwards & Haime , P. koninckii Milne Edwards & Haime , P. ogilviae (Felix) , P. ornata (Felix) , and P. circularia (Baron-Szabo) have to be considered junior synonyms of P. arachnoides (Knorr & Walch) because all of them are characterized by a corallite diameter of 2–3.5 mm (juvenile around 1.5. mm), corallite distance of 3–5 mm, and septa numbering from 24–48 and developed in 6 systems.

Milne Edwards & Haime (1851a, p. 98) described the species Astraea riemsdycki . Later, Milne Edwards (1857, p. 469) transferred this taxon to the genus Heliastraea and gave the dimensions d: 3–4 mm and s: 60– 70. Re-examination of the specimen (=? holotype of) Heliastraea riemsdycki , collection number M-561 [L 27] in the Michelin/Milne Edwards & Haime collection, MNHN by the author of this paper revealed that this specimen has all characterics of a subplocoid representative of Pleurocora and skeletal elements (d: 2–3.5 mm, juvenile 1.5 mm, s: up to 48) that closely correspond to the species P. arachnoides .

Type locality of species. Maastrichtian of The Netherlands (St. Pietersberg) .

Distribution. Uppermost Cenomanian of Egypt (Sinai), Turonian-Campanian of Austria (Gosau Group), Lower Coniacian and Santonian of France, Senonian of Ukraine (Delyatin, Iwano-Frankowskaya), Upper Santonian-Lower Campanian of Romania, Campanian of northern Spain (Torallola), Campanian-Maastrichtian of Belgium (Obourg, Mons), Maastrichtian of The Netherlands (St. Pietersberg), Danian of France