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Int. J. Biosci. 2015

International Journal of Biosciences | IJB | ISSN: 2220-6655 (Print), 2222-5234 (Online) http://www.innspub.net Vol. 6, No. 9, p. 74-81, 2015

RESEARCH PAPER OPEN ACCESS

Stegolophodon cautleyi from padri (Dhok Pathan Formation) Middle Siwaliks, Jhelum, Punjab, Pakistan

Khizar Samiullah1*, Riffat Yasin1, Farhat Jabeen1, Shahzad Ahmad1, Sajid Yaqub1, Khurram Feroz1, Saleem Akhtar1, Muhammad Akhtar2

1Department of Zoology, Government College University, Faisalabad, Pakistan 2Department of Zoology, New Campus, University of the Punjab, Lahore, Pakistan

Key words: , Late , Siwalik Hills, Proboscidean. http://dx.doi.org/10.12692/ijb/6.9.74-81 Article published on May 08, 2015

Abstract

The New fossil remains of Stegolophodon have been collected described and discussed from the site situated at the southeast of the Padhri (32 o 52’ 009 N: 73 o 18’ 297 E) outcrops of the Dhok Pathan Formation district Jhelum, Punjab, Pakistan at an altitude of about 1083 ft (Fig. 2). The described remains comprise second and third upper molars. After thorough investigation of the molar pattern, it is concluded that studied specimens clearly resembles to the species Stegolophodon cautleyi, which is found in the Late Miocene of the Siwaliks. The Stegolophodon suggests the evergreen forest. * Corresponding Author: Dr. Khizar Samiullah  [email protected]

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Introduction S. latidens. S. daratensis probably gave rise to S. Family includes genera Stegolophodon, stegodontoids while S. latidens to S. cristatus , Mammuthus, Loxodonta and . (Sarwar, 1977). Stegolophodon is an undoubtedly a pure Asiatic genus and it appeared in the Middle Miocene of Record of genus Stegolophodon from Europe has Japan (Yabe 1950; Shikama et al.,1956; Hatai, 1964). been reported by Osborn (1942) and (Bergounioux et Stegolophodon was a with four tusks al., 1956) based upon sublatidens and and a trunk. Its deposits are found in the Siwalik Stegolophodon saldanensis from Spain while the sediments of the Punjab at the time of occurrence in Africa has been reported by (Petrocchi, (Osborn,1929; Hooijer, 1955 Bakr et al.,1966; Sarwar, 1943, 1954; Singer et al., 1958) based upon new 1977) as well as in the Perim Island of India species, Stegolophodon sahabianus. Another African (Lydekker, 1886). It lived in the Miocene and Pliocene record is Stegolophodon lepersonnei from Nyamavi Epochs and started to decline towards the end of region of Congo. There are three recorded cases of the Pliocene (Pilgrim, 1913), Burma and China (Clift, occurrence of molars referred to Stegolophodon 1828; Chow, 1959). Stegolophodon stock might have latidens (Clift, 1828) in Japan from different localities got separated from its ancestral Gomphothere stock (Yabe, 1950). A broken left mandible of the genus somewhere in upper Miocene (Sarwar, 1977). Three Stegolophodon was also found in a mudstone boulder species of Stegolophodon discovered from the middle on the riverbed of the Nakagawa River at Katsura Miocene of Thailand which are Stegolophodon village, Ibaraki Prefecture, eastern Japan. The nasaiensis, Stegolophodon praelatidens and geological age of the fossil is assigned to the earliest Stegolophodon latiden (Olivier et al., 2009). Another middle Miocene based on fission track dating and species Stegolophodon xixiangensis has been chronostratigraphic data (Yoshiki et al., 2003). discovered from Hanzhong region of Shaanxi Province. Recent fieldwork in the Miocene basins of northern Thailand yielded the first complete molars of The Genus Stegolophodon is characterized by the Stegolophodon ever found in this country. A complete superior tusks with longitudinal enamel band. Lower M3 from middle Miocene and a partial mandible with tusks were small in size. Molar pattern consist of 4-5 M2-3 from early Miocene are described with new data ridge-plates with 4 to 6 conules which were on the evolution of the genus in South East Asia. A irregularly arranged in primitive species but new species is described in the early Miocene locality, transverse in advanced species. Accessory tubercles being the earliest known species of Stegolophodon were also present. M2 has 4-5 ridge-plates while M3 (Tassy, 1992). has less than 7 ridge-plates (Sarwar, 1977). The species Stegolophodon cautleyi described by The aim of this article is to emphasize the feebly (Lydekker, 1886) is known only from the Siwaliks of described fauna from the Siwalik Hills of Pakistan. In Pakistan and India where it appeared for the first this paper it has described these scarce remains, time at the base of the lower Chinji (Osborn, 1929). assigning them to the genus Stegolophodon. This species survived to the late Pliocene. A deciduous molar tooth of Stegolophodon cautleyi was also Abbreviations observed from middle Siwaliks of Perim Island in AMNH, American Museum of Natural History; IM, India (Khan et al., 2005). Among the known Indian Museum Calcutta, India; En. Th., Enamel Stegolophodonts, Stegolophodon cautleyi is the most thickness; H, Height of crown; L, Anteroposterior primitive and is ancestral to the other species of the length of the crown; W, Transverse width of the genus. From S. cautleyi, two lines of evolution can be Crown; mm, Millimeter; l, Left, r, Right; PUPC, derived. One leading to S. daratensis and the other to Punjab University Paleontological Collection; Ma,

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Million years ago; H/W index, Height/Width x100; arranged somewhat irregularly in the primitive W/L index, Width/Length x100; M2, upper second species but transversely linear in advanced species. Molar; M3, upper third Molar. Accessory tubercles or conules present in the primitive species. A median cleft present at least in Materials and methods the anterior ridge-plates. Second molar has 4-5 ridge- The studied specimens were collected from Padri, plates while third molar has less than 7 ridge-plates. district Jhelum from Dhok Pathan type locality during the years 2008-2010. The specimens are Stegolophodon cautleyi (Lydekker, 1886). properly cleaned and washed in the laboratory. Fine needles, camel hair brushes as well as light hammer is Type specimen: (Lectotype) l. M, Brit. Mus. M. 2705 used to remove unwanted siliceous or clay material. (Lydekker, 1886). The broken parts are assembled by using various gums and adhesives such as Araldite, Elphy and Type locality: Perim Island, India. Peligon. The specimens are catalogued such as PUPC No. 09/13, the upper figure denotes the collection Stratigraphic range: Middle Siwaliks. year while the lower one shows the serial no. of the respective year. The measurements of the specimens Distribution: The species is known only from the are made by metric Vernier Calipers and then tables Siwaliks of Pakistan and India where it appeared for are formulated. The photographs of the described the first time at the base of lower Chinji. The species specimens are taken with Digital Camera and hard survived to the late Pliocene and its latest record is copies were prepared by using Adobe Photoshop. from the upper levels of the Dhok Pathan zone of the Middle Siwalik. Systematic Palaeontology Order (Illiger, 1811) Diagnosis: Median cleft more or less prominent. Suborder (Osborn, 1910) Conules of the anterior ridge plates somewhat Family ELEPHANTIDAE (Schlesinger, 1917) dislocated. Each ridge plate is surmounted by 4 to 5 Subfamily STEGOLOPHODONTINAE conules in M3 and by 5 to 6 in intermediate molars. (Osborn, 1910). Small conules or accessory tubercles present in the transverse valleys. M3 4 crested. Genus STEGOLOPHODON (Takai et al., 1961; Osborn, 1936). Material: PUPC No. 09/120; a well preserved M2 and PUPC No. 09/13; an anteriorly damaged M3. Type species: Stegolophodon latidens (Clift, 1828). Locality: Padri (Figs 1&2), Dhok Pathan Formation Distribution: Stegolophodon is a purely Asiatic genus (Middle Siwaliks), District Jhelum, Punjab, Pakistan. and its record from outside Asia is erroneous. It appeared for the first time in the middle Miocene of Description Japan (Takai and Fujii, 1961). It is also distributed in PUPC 09/120 (Fig. 3) the Siwaliks of Pakistan and Perim Island of India. M2 The preservation of studied tooth is excellent. It is Diagnosis: Superior tusks with longitudinal enamel extremely brachyodont and extremely narrow band. Lower tusks present but small in size. Molar crowned. The molar has four preserved ridge-plates pattern transitional between and while first ridge-plate has broken down. The anterior Stegodon. Ridge-plates semibunodontine with few two ridge-plates are worn with first in middle worn (usually 4 to 6) distinct conelets. The conelets condition and second in early worn condition while

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Int. J. Biosci. 2015 posterior two are unworn. All the ridge-plates are plates are transversally arranged but that of fourth directing upward and have a conspicuous median are irregularly arranged. The ridge-plates are widely cleft. The Second ridge-plate is occlusally divided into spaced having prominent intermediate valleys which four conelets with a posterior accessory tubercle. are deposited with cement. Enamel is fairly thick, Third ridge-plate has three complete but one partly almost smooth and simple. The first and second damaged conelet. The fourth ridge-plate is unworn ridge-plates are in use and have been changed into having four irregularly arranged conelets which are complete enamel loops except the third and fourth blunt, isolated and rounded. The fifth ridge-plate has where the conelets are still distinct and rounded. three large, prominent conelets and two smaller Roots are nicely preserved with large amounts of conelets. The conelets of first, second and third ridge- sediments deposited in between the roots.

Table 1. Measurements (in mm) of second (PUPC 09/120) and third upper molars (PUPC 09/13), referred to Stegolophodon cautleyi (Lydekker 1886). (PUPC 09/120) (PUPC 09/13) M2 M3 Preserved antero-posterior crowned length 165 210 Transverse width of 2nd ridge-plate 73 - Transverse width of 3rd ridge-plate 70 110 Transverse width of 4th ridge-plate 63 90 Transverse width of 5th ridge-plate 60 75 Preserved crowned height 48 48 H/W index 65 43 W/L index 44 52 Enamel thickness 7 7

Table 2. Comparative measurements (in mm) of studied specimens with different species of genus Stegolophodon (comparative data taken from 7 *Studied specimens). Specimens, position and species L W H H/W index W/L index En. th. U.Z. 69/633 (rM2) Stegolophodon cautleyi - 95 48 50 - 6 U.Z. 69/330 (rM3) S. cautleyi - 87 46 52 - 7.5 *PUPC 09/120 (M2) S. cautleyi 165 73 48 65 44 7 *PUPC 09/13 (M3) S. cautleyi 210 110 48 43 52 7 U.Z. 70/24 (M3) S. daratensis 126 87 31 - 54 6.2 U.Z. 72/5 (M3) S. daratensis 163 88 30 - 54 6.3 AMNH 21978 (M3) S. latidens 140 76 - - 54 - PI.XXXVIII (M3) S. latidens [11] 300 101 - - 34 -

PUPC 09/13 (Fig. 3) plates are completely damaged showing only traces of M3 enamel. The third ridge-plate shows only two worn The tooth is poorly preserved and is narrow crowned, conelets at the outer margins, on the buccal side and brachyodont with only two preserved ridge-plates. It other on the lingual side. Fourth ridge-plate is nicely is completely damaged at the anterior end but a partly preserved. It has four partly worn conelets with damaged third ridge-plate and completely preserved posterior accessory tubercle. The conelets of fourth fourth and fifth ridge-plates are present at the ridge-plate are not strictly transverse but they are posterior end of the tooth. The first and second ridge- easily distinguished because of little wear. The fifth

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Int. J. Biosci. 2015 ridge-plate is also preserved with five conelets which they cannot be referred to any of these. In both are irregularly arranged. The ridge-plates are closely studied specimens, the conules are arranged in spaced with inconspicuous intermediate valleys. Only transverse plates. Such type of arrangement is trace amount of cement is present. Enamel is thick, displayed by the teeth of , smooth and simple. The roots are nicely preserved Stegolophodon, Stegodon and . In and sediments and minerals are deposited with roots. Tetralophodon the conules are much compressed as compared to those of the other three genera. The ridge plates are widely spaced in the molar teeth of the genera Stegolophodon and Stegotetrabelodon (Osborn, 1942), whereas these are closely oppressed in those of the genus Stegodon (Lydekker, 1886). Thus, the specimens under study can either be referred to the genus Stegolophodon or to the genus Stegotetrabelodon. The genus Stegolophodon, being chronologically older than the genus Fig. 1. Type locality Padri, Dhok Pathan Formation, Stegotetrabelodon, has more deep and prominent Middle Siwaliks, district Jhelum, Punjab, showing the median cleft. The molar structure of PUPC 09/120 studied specimen (PUPC 09/13). and PUPC 09/13 described above are quite typical of the genus Stegolophodon due to prominent and deep Discussion and comparisons median cleft, dislocation of the conelets of the ridge- According to (Sarwar, 1977), the crown is plates and the presence of accessory tubercles shown brachyodont in proboscidea except the later forms by these specimens clearly favor their inclusion in the such as Elephas, Mammuthus and Loxodonta. Since species S. cautleyi (Tables 1 and 2). the crown of PUPC 09/120 and PUPC 09/13 are low,

Fig. 2. Map of the Potwar Plateau and generalized stratigraphic dates of the Siwalik formations; the studied locality is encircled and the studied chronostratigraphic context is shaded (data from Johnson et al., 1982 ; Barry et al., 2002; Nanda, 2002; Dennell et al., 2006 ; Cohen et al., 2008).

When compared with the lectotype molar (Brit. Mus. 09/120, 110 mm in PUPC 09/13 and 112 mm in the M. 2705 by Lydekker, 1886) of the species S. cautleyi, lectotype). This could be attributed to the individual the examined specimens are somewhat smaller difference. The deep median cleft and the presence of regarding the transverse width (73 mm in PUPC posterior and median accessory tubercles are

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Int. J. Biosci. 2015 primitive proboscidean characters described by 1964) are devoid of accessory tubercles and their (Osborn, 1921) shared with the specimens under ridge-plates are quite transversely linear (Sarwar, study. On the other hand, the Japanese species i.e. S. 1977) and they are more progressive than the S. pseudolatidens (Yabe, 1950) and S. miyokoae (Hatai, cautleyi of the Siwaliks.

Fig. 3. 1. Stegolophodon cautleyi; PUPC 09/120, upper second molar (M2). Views are occlusal (1a), labial (1b) and lingual (1c). 2. Stegolophodon cautleyi; PUPC 09/13, upper third molar (M3). Views are occlusal (2a), labial (2b) and lingual (2c). Scale bar 20 mm.

This is also supported by the fact that S. hueiheensis cautleyi through the loss of accessory tubercles and (Chow, 1959) is known from Pleistocene and in molar more regular arrangement of the conelets of the structure it compares well with the Japanese species. ridge-plates and hence the latter might be ancestral to If it considers the Japanese species as of Pliocene age, the former. S. daratensis is primitive as compared to then S. cautleyi which is structurally more primitive S. latidens in the number of ridge-plates but is than the other known species, could be taken as advanced in the absence of accessory tubercles which ancestral to the others and the waves of migration are still retained by S. latidens. Hence, both the were probably from the Siwaliks to Japan and China species, S. daratensis and S. latidens seems to be (Sarwar, 1977). Both dental features and the independent off-shoots from some common ancestor, stratigraphic level, indicate that they belong to the probably the S. cautleyi (Sarwar, 1977). most primitive species of the genus, Stegolophodon cautleyi. S. cautleyi differs from the species S. Conclusions daratensis in which ridge-plates are more regular and The genus Stegolophodon is an Asiatic genus and was accessory tubercles are absent. It also differs from S. first observed from the middle Miocene of Japan. In cristatus which is highly progressive form due to the Siwaliks of Pakistan, it appeared first at the base having transversely linear ridge-plates comprising of lower Chinji. It survived from Miocene to early sharp conelets and open valleys (Bakr and Qureshi, Pleistocene. Stegolophodon is characterized by the 1966). The examined specimens are distinguished presence of four tusks and a trunk. Molar pattern of from that of the S. pseudolatidens which has got six Stegolophodon consist of 4-5 ridge-plates with 5 to 6 conelets in each ridge-plate and enamel rugosity transversely arranged conules, which are rounded, (Takai and Fujii, 1961). Stegolophodon cautleyi is blunt and isolated. Accessory tubercles and a supposed to be the ancestor of S. daratensis and S. prominent median cleft are also present in the latidens. This is supported by the fact that the third anterior parts of the teeth. Fossil record of genus molar of S. daratensis can be derived from that of S. Stegolophodon has been observed from Europe,

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Africa, Japan, Thailand and Asia including Siwaliks of Hooijer DA. 1955. Fossil Proboscidea from the Pakistan and Perim Island of India. Malay Archipelago and the Punjab. Zoologicus Verhandlungen 28, 1-146. References Bakr A, Qureshi RA. 1966. Three new elephantids Illiger CD. 1811. Prodromus Systematis from the Upper Siwaliks. Journal of Science Mammalium et Avium Additis Terminis Zoographicis Research. University of the Panjab 1(1), 93-103. Uttriusque Classis, Salfeld.

Barry J, Morgan M, Flynn L, Pilbeam D, Johnson GD, Zeitler P, Naeser CW, Johnson Behrensmeyer AK, Raza S, Khan I, Badgely C, NM, Summers DM, Frost CD, Opdyke D, Hicks J, Kelley J. 2002. Faunal and Environmental Tahirkheli RAK. 1982. The occurrence and fission- change in the Late Miocene Siwaliks of Northern track ages of Late Neogene and Quaternary volcanic Pakistan. Paleobiology 28, 1-72. sediments, Siwalik group, northern Pakistan. Palaeogeography, Palaeoclimatology, Palaeoecology Bergounioux FM, Crouzel F. 1956. Presence de 37, 63-93. Tetralophodon longirostris dans le Vindobonien inferieur de Tunisie. Bulletin de la Societe Geologique Khan MA, Ghaffar A, Ali Z, Farooq U, Bhatti de France 6, 547-558. ZH, Akhtar M. 2005. Report on Mammalian Fossils of Chinji Formation, Dhulian, Pakistan. American Chow M. 1959. New species of fossil Proboscidea Journal of Applied Sciences 2(12), 1619-1628. from South China. Acta Palaeontologica Sinica 7, 251- 258. Lydekker R. 1886. Indian Tertiary vertebrate: Siwaliks. Mammalia. Paleontologica Indica 10(4), 1- Clift W. 1828. On the fossil remains of two new 22. species of Mastodon and of other vertebrated , found on the left bank of the Irawadi. Nanda AC. 2002. Upper Siwalik mammalian faunas Transactions of the Geological Society of London 2, of India and associated events. Journal of Asian Earth 369-375. Sciences 21, 47-58.

Cohen KM, Gibbard PL. 2008. Global Olivier O, Yaowalak C, Chotima Y, Pannipa T, chronostratigraphical correlation table for the last 2.7 Mana R, Bernard M, Jean-Jacques J. 2009. million years. Episodes 31, 243-247. New proboscideans (Mammalia) from the Middle Miocene of Thailand. Zoological Journal of the Dennell R, Coard R, Turner A. 2006. The Linnean Society 155(3), 703-721. biostratigraphy and magnetic polarity zonation of the http://dx.doi.org/10.1111/j.1096-3642.2008.00456.x Pabbi Hills, northern Pakistan: An Upper Siwalik (Pinjor Stage) Upper Pliocene-Lower Pleistocene Osborn HF. 1910. The Age of in Europe, fluvial sequence. Palaeogeography, Asia and North America, the Macmillan Co., New Palaeoclimatology, Palaeoecology 234, 168-185. York. 8 p. 635.

Hatai K. 1964. Discovery of Miocene molar Osborn HF. 1921. The evolution, phylogeny and from the Sen-non district, Miyagi Prefecture, classification of the Proboscidea. American Museum Northeast Japan. Research Bulletin - Saito Ho-on Kai Novitates New York 1, 1-15. Museum 28, 1-5. Osborn HF. 1929. New Eurasiatic and American

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Proboscideans. American Museum November, New Prefecture. Trans. Paleontological Society of Japan York 393, 1-23. 24, 285-289.

Osborn HF. 1936. Proboscidea, American Museum Singer R, Hooijer DE. 1958. A Stegolophodon of Natural History Press, New York 1, 1-802. from South Africa. Nature, London 182, 101-102. http://dx.doi.org/10.1038/182101a0 Osborn HF. 1942. Proboscidea, 2, 805-1675. Takai F, Fujii S. 1961. Stegolophodon Petrocchi C. 1943. I giacimento fossilifero di Sahabi. pseudolatidens from the Miocene Yokawa group in Collection Scientists Documentation. A Cura (Min. Toyama Prefecture, Japan, Professor Jiro Makiyama A.I., 9), 12. Memorial Volume. 225-228 P.

Petrocchi C. 1954. I Proboscidati di Sahabi. Rend. Tassy P, Anupandhanant P, Ginsburg L, Mein Accademia Nazionale XL (4-5), 1-74. P, Ratanasthien B, Suteethorn V. 1992. A new Stegolophodon (Proboscidea, Mammalia) from the Pilgrim GE. 1913. The correlation of the Siwaliks early Miocene of northern Thailand: Geobios 25(4), with ’s horizons of Europe. Survey of India 511–523. 43, 264-326. Yabe H. 1950. Three alleged occurrences of Sarwar M. 1977. Taxonomy and distribution of the Stegolophodon latidens (Clift) in Japan. Proceedings Siwalik Proboscidea. Bulletin Department of Zoology of the Japan Academy 26, 61-65. University of the Punjab Lahore 10, 1-72. Yoshiki K, Yukio Y, Yoshikazu H, Hiroyuki O, Schlesinger G. 1917. Die Mastodonten des K. K. Masao A. 2003. A Middle Miocene mandible of Naturhistorischen Hofmuseums. Denk. Naturhist. Stegolophodon (Proboscidea, Mammalia) discovered Hofmus. I. Geol Pal., Reihe I, 1-230 P. in Katsura Village, Ibaraki Prefecture; eastern Japan. Earth Science 57(1), 49-59. Shikama T, Kirii Y. 1956. A Miocene Stegolophodon from yatuo Group in Toyama

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