Knightella irregularis ( Longstaff, 1933 )

Ketwetsuriya, Chatchalerm, Karapunar, Baran, Charoentitirat, Thasinee & Nützel, Al- Exander, 2020, Middle Permian (Roadian) gastropods from the Khao Khad Formation, Central Thailand: Implications for palaeogeography of the Indochina Terrane, Zootaxa 4766 (1), pp. 1-47 : 38

publication ID

https://doi.org/ 10.11646/zootaxa.4766.1.1

publication LSID

urn:lsid:zoobank.org:pub:B1B5DA41-5035-4783-8D47-28857B6305AE

DOI

https://doi.org/10.5281/zenodo.3803809

persistent identifier

https://treatment.plazi.org/id/03B587AB-4F12-155B-FF51-7A13FB44FA3B

treatment provided by

Carolina (2020-04-23 19:36:32, last updated 2024-11-29 15:00:46)

scientific name

Knightella irregularis ( Longstaff, 1933 )
status

 

Knightella irregularis ( Longstaff, 1933)

( Fig. 25 View FIGURE 25 B–E)

Knightia irregularis Longstaff, 1933: 118 , pl. 12, figs 4–5; Knight, 1941: 164, pl. 49, fig. 6a–b.

Material. Two specimens: ESKU-19- LP 41, 84.

Dimensions (mm): ESKU-19- LP 41: height = c. 16.6; width = 6.1. ESKU-19- LP 84: height = 8.9; width = 4.0; apical angle = 42 º.

Description. Shell high-spired, slender; largest specimen consisting of 10 whorls; protoconch smooth, seemingly about two orthostrophic whorls; whorls low, gently increasing; whorls smooth; whorl face evenly convex or somewhat pendent with periphery at mid-whorl or somewhat below; sutures moderately deep, distinct; base evenly convex, rounded; anomphalous; aperture unknown.

Remarks. The present specimens closely resemble the type species, Knightella irregularis ( Longstaff, 1933) from the Carboniferous, Scotland as re-described and illustrated by Knight (1941, p.165, pl. 49, fig. 6a–b), although the present specimens are much larger. The general features of this species (i.e., high spire, sharply rounded and somewhat pendent whorl profile, a body whorl which is two-fifths of the total height, rounded base, anomphalous shell and slightly protruding protoconch) are obviously identical with the present specimens. Other similar species are K. hydrobiformis Nützel, 2012 and Knightella sp. from the Middle Permian Akasaka Limestone of Japan (Nützel & Nakazawa, 2012) and also several Knightella species which have been reported by Nützel (1998) from the Pennsylvanian of the USA. However, these species are smaller and have less convex whorls. Loxonema karabolkensis Licharev, 1975 (p. 78, pl. 13, figs 5–8) from the Pennsylvanian of Russia is similar but it differs in having a dense spiral ornament on the whorls. The present specimens are also similar to Protostylus ; however, this genus has flatter whorls. This is the first known member of the genus Knightella in Thailand which extends the range of this species and genus to the Middle Permian and expands its distribution to the eastern Palaeo-Tethys.

Knight, J. B. (1941) Paleozoic gastropod genotypes. Geological Society of America Special Paper, 32, 1 - 510. https: // doi. org / 10.1130 / SPE 32 - p 1

Licharev, B. K. (1975) Carboniferous gastropods from the region of the River Karabolka. Trudy Vsesoyuzniei Navcho-Issledovatelbskii Geologicheskii Institut, 206, 5 - 183.

Longstaff, J. D. (1933) A revision of the British Carboniferous Loxonematidae, with descriptions of new forms. Quarterly Journal of the Geological Society of London, 89 (2), 87 - 124. https: // doi. org / 10.1144 / GSL. JGS. 1933.089.01 - 04.05

Nu ¨ tzel, A. & Nakazawa, K. (2012) Permian (Capitanian) gastropods from the Akasaka Limestone (Gifu Prefecture, Japan). Journal of Systematic Palaeontology, 10, 103 - 169. https: // doi. org / 10.1080 / 14772019.2010.549659

Gallery Image

FIGURE 25. A, Donaldospira sp., ESKU-19-LP 85. B–E, Knightella irregularis (Longstaff, 1933), B–C, ESKU-19-LP 41. D–E, ESKU-19-LP 84. F–H, Protostylus sp., F, ESKU-19-LP 39. G–H, ESKU-19-LP 64. I–N, Trypanocochlea lopburiensis sp. nov. I, M, ESKU-19-LP 210, holotype; oblique view of early whorls to show protoconch. J, ESKU-19-LP 201, paratype. K, ESKU-19-LP 203, paratype. L, ESKU-19-LP 206, paratype; lateral view of early whorls to show protoconch. N, ESKU-19-LP 221, paratype. O–R, Streptacis? khaokhadensis sp. nov., O–P, ESKU-19-LP 214, holotype. Q–R, ESKU-19-LP 213, paratype. Scale bars represent: 2 mm (A–H); 200 μm (I–R).

LP

Laboratory of Palaeontology

Kingdom

Animalia

Phylum

Mollusca

Class

Gastropoda

SubClass

Caenogastropoda

SuperFamily

Orthonematoidea

Family

Palaeostylidae

Genus

Knightella