Lepisosteus indicus

Lepisosteus indicus Temporal range: Maastrichtian to Danian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Clade:	Ginglymodi
Order:	Lepisosteiformes
Family:	Lepisosteidae
Genus:	Lepisosteus
Species:	†L. indicus
Binomial name
†Lepisosteus indicus (Woodward, 1890)
Synonyms
†Belonostomus indicusWoodward, 1890

Lepisosteusindicus, the Indian gar ^[1] , is an extinct species of gar known from the Late Cretaceous (Maastrichtian) and early Paleocene of India. It is known from a single articulated but poorly-preserved skull and a lost set of vertebrae from the Lameta Formation, ^[2] in addition to numerous isolated scales and teeth from the Lameta Formation and Intertrappean Beds.

Taxonomy

It was initially described by Woodward (1890) as a species of unrelated aspidorhynchid fish ( Belonostomus indicus) until he reclassified it as a gar in 1909. L. indicus is generally thought to belong to the genus Lepisosteus , a genus that contains several modern gar species that are found in eastern North America. ^[2] The presence of this species in India suggests that the genus had a much larger range in prehistoric times, and it is thought to be the easternmost known Lepisosteus species overall. ^[3] However, some recent studies suggest that it may be only a stem-member of Lepisosteus, as some of the synapomorphies that were originally thought to be exclusive to Lepisosteus , and thus supporting this species' placement in that genus, have been found to be non-indicative. However, it is likely to be more closely related to Lepisosteus than to any other gar. ^[4]

Occurrence

Although only a single, crushed, partial articulated specimen is known representing an individual of about 75–90 centimetres (2.46–2.95 ft) in length, ^[2] the ganoid scales and teeth assigned to this species are abundant in Maastrichtian and early Paleocene freshwater deposits of India, including Madhya Pradesh, Maharashtra, and Telangana. ^{[5] [6] [7]}

It is possible that this species or its close relatives had a wider geographic and temporal distribution: isolated gar scales (considered Lepisosteidae indet.) are known from the Kallamedu Formation of Tamil Nadu in southern India, which is contemporaneous with the Lameta Formation. ^[8] In addition, the partial trunk of a small-sized gar that may potentially be L. indicus is known from the Late Paleocene-aged Palana Formation in Rajasthan, India, ^[9] while isolated Lepisosteus scales are known from the middle Eocene (Lutetian)-aged Kuldana Formation of Kohat, Pakistan, representing the youngest record of gars on the subcontinent. The Pakistani Lepisosteus have been previously referred to L. indicus, but analysis of their scales indicates some differences from L. indicus, and a closer similarity to the modern longnose gar. ^[3]

References

1. Grande, Lance (2010). "An Empirical Synthetic Pattern Study of Gars (lepisosteiformes) and Closely Related Species, Based Mostly on Skeletal Anatomy. the Resurrection of Holostei". Copeia. 2010 (2A): iii–871. ISSN   0045-8511. JSTOR   20787269.
2. Woodward, Arthur Smith; Diener, Carl; Cossmann, Maurice; Buckman, S. S. (1909). The Brachiopoda of the Namyau Beds, Northern Shan States, Burma: By S. S. Buckman. Sold at the Office of the Geological Survey.
3. Gayet, M.; De Broin, F.; Rage, J. C. (1987). "Lower Vertebrates from the Early-Middle Eocene Kuldana Formation of Kohat (Pakistan): Holostei and Teleostei, Chelonia, and Squamata". Costributions from the Museum of Paleontology. 27 (7). hdl:2027.42/48528.
4. Doran Brownstein, Chase; Yang, Liandong; Friedman, Matt; Near, Thomas J (2023-01-01). "Phylogenomics of the Ancient and Species-Depauperate Gars Tracks 150 Million Years of Continental Fragmentation in the Northern Hemisphere". Systematic Biology. 72 (1): 213–227. doi:10.1093/sysbio/syac080. ISSN   1063-5157.
5. Verma, Omkar; Khosla, Ashu; Lucas, Spencer G. (2024-09-01). "Late Cretaceous-Early Palaeocene Lepisosteiform and Siluriform fish remains from Central India: palaeoecological, palaeoenvironmental and palaeobiogeographical implications". Cretaceous Research. 161: 105915. Bibcode:2024CrRes.16105915V. doi:10.1016/j.cretres.2024.105915. ISSN   0195-6671.
6. Lourembam, Ranjit Singh; Prasad, Guntupalli V. R.; Grover, Pooja (2017). "Ichthyofauna (Chondrichthyes, Osteichthyes) from the Upper Cretaceous intertrappean beds of Piplanarayanwar, Chhindwara District, Madhya Pradesh, India". Island Arc (in Japanese). 26 (1): e12180. Bibcode:2017IsArc..26E2180L. doi:10.1111/iar.12180. ISSN   1440-1738.
7. Prasad, G. V. R.; Sahni, Ashok (1987). "Coastal-plain microvertebrate assemblage from the terminal cretaceous of Asifabad, Peninsular India". Journal of the Palaeontological Society of India. 32: 5–19. doi:10.1177/0971102319870102. ISSN   0552-9360.
8. Prasad, Guntupalli V. R.; Verma, Omkar; Flynn, John J.; Goswami, Anjali (2013-11-01). "A new Late Cretaceous vertebrate fauna from the Cauvery Basin, South India: implications for Gondwanan paleobiogeography". Journal of Vertebrate Paleontology. 33 (6): 1260–1268. Bibcode:2013JVPal..33.1260P. doi:10.1080/02724634.2013.777348. ISSN   0272-4634.
9. Kumar, K.; Rana, R. S.; Paliwal, B. S. (2005). "Osteoglossid and Lepisosteid Fish Remains from the Paleocene Palana Formation, Rajasthan, India". Palaeontology. 48 (6): 1187–1209. Bibcode:2005Palgy..48.1187K. doi:10.1111/j.1475-4983.2005.00519.x. ISSN   1475-4983.