Species: Hallopora andrewsi (Nicholson, 1874)
Taxonomic History (Nickles & Bassler, 1900; Under Callopora andrewsi)
- 1874 Chaetetes pulchellus (not of Milne-Edwards & Haime) Nicholson, Quar. Jour. Geol. Soc. London, XXX, p. 503, pl. xxix, 5-5b.
- 1875 Chaetetes pulchellus (not of Milne-Edwards & Haime) Nicholson, Pal. Ohio, II, p. 195, pl. xxi, 5, 5a.
- 1881 Monticulipora (Heterotrypa) andrewsi Nicholson, Genus Monticulipora, p. 128, fig. 21, pl. v, 1, 1a.
- 1882 Callopora andrewsi Ulrich, Jour. Cincinnati Soc. Nat. Hist., V, p. 252.
- 1883 Monticulipora andrewsii (Van Cleve) Hall, Twelfth Ann. Rep. Indiana Geo. Nat. Hist., p. 249, pl. xi, 9.
- 1888 Monticulipora andrewsii James and James, Jour. Cincinnati Soc. Nat., Hist., X, p. 178.
- 1894 Monticulipora andrewsii J.F. James, Jour. Cincinnati Soc. Nat. Hist., XVI, p. 200.
Note: Probably all species referred to as Hallopora from the type Cincinnatian are actually Parvohallopora. (Steven Holland, UGA Strat Lab 2013)
Map point data provided by iDigBio.
- C3 Sequence (Corryville)
- C2 Sequence (Bellevue)
Identification in Hand Sample
- Zoarium Morphology: Ramose; 6-12 mm
- Zoecia: 7 in 2mm; surrounded by variable number of mesopores
- Mesozooids: Numerous
- Monticules: Low and rounded
- Maculae: Composed of larger apertures, with more numerous mesopores
Hallopora andrewsi from the McMillan Formation of Georgetown, Ohio (OUIP 876)
- Zooarium ramose, 6-12 mm in diameter. Surface typically with low, rounded monticules composed of larger apertures and more numerous mesopores. Zooecia 7 in 2 mm, surrounded by a variable number of angular or subcircular mesopores. Tabulations of zooecia variable.
- “Corallum variable in form, usually of subcylindrical branches, which have a diameter of from 2 to 6 lines, sometimes forming flattened and expanded subpalmate fronds, sometimes inosculating. Corallites thin-walled, polygonal, unequal in size, about eight of the average ones occupying the space of 1 line. Surface exhibiting rounded or somewhat stellate groups of larger corallites, of which two or three occupy the space half a line, and which sometimes have very minute intermediate tubuli between them. These groups of larger corallites generally comprise from five to seven individuals, and they are placed about 1 line apart; they are very slightly or not at all elevated above the general surface so that there are no conspicuous tubercles.
- “The characters of this species are so well marked as to render its recognition very easy, even in small fragments.” – Nicholson, loc. cit.
- Internally this species exhibits very beautifully the peculiar structure of the genus Callopora. Toward the surface, the walls are much thickened and ring-like and are separated from each other by a set of small rounded mesopores. In longitudinal sections, the zooecia and mesopores are seen to be crossed by a well-developed series of straight diaphragms, which are very close together in the mesopores.