| Basic info | Taxonomic history | Classification | Included Taxa |
| Morphology | Ecology and taphonomy | External Literature Search | Age range and collections |
Sphenotreta acutirostris
Taxonomy
Atrypa acutirostra was named by Hall (1847).
It was recombined as Rhynchonella acutirostris by Hall (1859); it was recombined as Zygospira acutirostris by Raymond (1911); it was recombined as Sphenotreta acutirostris by Cooper (1956).
It was recombined as Rhynchonella acutirostris by Hall (1859); it was recombined as Zygospira acutirostris by Raymond (1911); it was recombined as Sphenotreta acutirostris by Cooper (1956).
Synonymy list
| Year | Name and author |
|---|---|
| 1847 | Atrypa acutirostra Hall p. 21 figs. pl. 4 bis, fig. 6, |
| 1859 | Rhynchonella acutirostris Hall p. 65 |
| 1911 | Zygospira acutirostris Raymond p. 227 figs. pi. 34, figs. 15-22 |
| 1956 | Sphenotreta acutirostris Cooper pp. 664 - 665 figs. Plate 124, F, figures 32-38 ; plate 143, H, figures 37-40 |
Is something missing? Join the Paleobiology Database and enter the data
|
|
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
†Sphenotreta acutirostris Hall 1847
show all | hide all
Diagnosis
| Reference | Diagnosis | |
|---|---|---|
| G. A. Cooper 1956 | Shell small, triangular in outline with the widest part in the anterior half; posterolateral margins straight, forming an angle of 80°. Anterolateral margins narrowly rounded ; anterior margin truncated ; anterior commissure sulcate. Surface marked by lo to 15 narrowly rounded to subangular costae.
Pedicle valve gently and evenly convex in lateral profile ; broadly subcarinate in anterior profile. Umbo narrowly convex, marked by a prominent median costa which extends from umbo to anterior margin maintaining its prominent character throughout. Median costa and i or 2 on each side form an indistinct fold. Flanks sloping moderately to the margins, not swollen. Brachial valve gently convex in the median three-fourths but turned in narrowly toward the pedicle valve in the anterior quarter. Anterior profile sulcate, with narrowly convex flanks and precipitous sides. Umbo and median region sulcate; sulcus deep, deepest medially where a narrow groove corresponds to the exaggerated median costa of the pedicle valve. Sulcus occupied by 2 to 4 costae depending on age. |
Measurements
No measurements are available
|
|
||||
|
|
||||
|
|||||
|
|
||||
|
|
||||
| Source: o = order, c = class, p = phylum, uc = unranked clade | |||||
| References: Nesnidal et al. 2013, Aberhan et al. 2004 | |||||
Collections (37 total)
| Time interval | Ma | Country or state | Original ID and collection number |
|---|---|---|---|
| Chazyan | USA (Vermont) | Zygospira acutirostris (172202 172203) | |
| Chazyan | Canada (Quebec) | Zygospira acutirostris (172350) | |
| Chazyan | USA (New York) | Rhynchonella acutirostris (164475) Zygospira acutirostris (42808 56212 56214 56215 171704 171706 171707 171711 171713 171798 172187 172195 172221 172222 172223 172227 172325 172329 172330 172331 172342 172346) | |
| Chazyan | Canada (Ontario) | Zygospira acutirostris (172204) | |
| Caradoc | USA (Virginia) | Zygospira acutirostris (33934 33935 33936 33937) | |
| Ashbyan | USA (Virginia) | Zygospira acutirostris (33938 33980 33981 33982 33983 33984) |