PALEVO 1631-0683 Elsevier S1631-0683(17)30006-4 10.1016/j.crpv.2017.01.002 Research article General Palaeontology, Systematics and Evolution (Vertebrate Palaeontology) General Palaeontology, Systematics and Evolution (Vertebrate Palaeontology) First mammal of Gondwanan lineage in the early Eocene of India Premiers mammifères de la lignée gondwanienne dans l’Éocène inférieur de l’Inde Kapur Vivesh V. viveshkapur@gmail.com viveshvir_kapur@bsip.res.in a Das Debasis P. b Bajpai Sunil a Prasad Guntupalli V.R. c Birbal Sahni Institute of Palaeosciences, 53, University Road, 226007 Lucknow, Uttar Pradesh, India Birbal Sahni Institute of Palaeosciences 53, University Road Lucknow Uttar Pradesh 226007 India Shell Technology India Pvt. Ltd., RMZ Centennial Campus B, 8B, Kundanahalli Main Road, 560048 Bangalore, Karnataka, India Shell Technology India Pvt. Ltd., RMZ Centennial Campus B 8B, Kundanahalli Main Road Bangalore Karnataka 560048 India Department of Geology, University of Delhi, 110007 Delhi, India Department of Geology, University of Delhi Delhi 110007 India 16 7 S1631-0683(17)X0006-7 721 737 © 2017 Académie des sciences. Published by Elsevier B.V. All rights reserved. 2017 Académie des sciences Full (PDF)

Based on well-preserved lower dentition, a new adapisoriculid from the Cambay Shale Formation (basal Eocene, ∼54.5 Ma) in the open cast lignite mine of Vastan, Gujarat State, western India, is described. Indolestes kalamensis gen. et sp. nov adds significantly to the diversity of basal eutherians from Vastan as it represents a family hitherto not known from the Eocene of the Indian Subcontinent. Phylogenetic analysis suggests that Indolestes is derived relative to Deccanolestes and Afrodon, but primitive relative to the European adapisoriculids Bustylus and Adapisoriculus. The new data from the early Eocene provide evidence for continued survival of a Gondwanan mammal lineage following the Deccan volcanic activity (Cretaceous–Paleogene transition) in the Indian Subcontinent.

Basée sur une dentition inférieure, la description d’un nouvel adapisoriculidé de la formation Cambay Shale (Éocène basal, environ 54,5 Ma) dans la mine à ciel ouvert de Vastan, État de Gujarat, Inde occidentale, est ici présentée. Indolestes kalamensis gen. et sp. nov. ajoute de manière significative à la diversité des euthériens de base de Vastan, en ce qu’il représente une famille jusqu’à présent inconnue dans l’Éocène du sous-continent Indien. Une analyse phylogénétique suggère que Indolestes serait dérivé de Deccanolestes et Afrodon, mais primitivement des adapisoriculidés européens Bustylus et Adapisoriculus. Les nouvelles données sur l’Éocène inférieur fournissent l’évidence d’une survie continue d’une lignée mammalienne gondwanienne suivant l’activité volcanique du Deccan à la transition Crétacé–Paléogène dans le sous-continent Indien.

 Adapisoriculidae, Cambay Shale, Early Eocene, Gondwana, India, Mammal Adapisoriculidés, Shale de Cambay, Éocène inférieur, Gondwana, Inde, Mammifères presented Handled by Lars van den Hoek Ostende Introduction

Small mammals belonging to the family Adapisoriculidae have perplexed paleontologists for over a century and have been variously assigned to different groups including didelphids, nyctitherids, leptidectids, mixodectids and palaeoryctids owing to the presence of several plesiomorphic dental characters (e.g., De Bast et al., 2012). These characters include transverse elongation of teeth, prominent parastyle and stylocone, variable stylar cusps, long prepara- and postmeta-cristae on a wide stylar shelf, rectilinear or dilambdodont centrocrista, separation of paracone and metacone down to their bases, reduced height difference between trigonid and talonid compared to cimolestids, and cristid obliqua extending high on to the posterior wall of the trigonid. Currently, adapisoriculids are represented by seven genera (Deccanolestes, Afrodon, Bustylus, Adapisoriculus, Garatherium, Remiculus and Proremiculus) with the oldest record (Deccanolestes) known from the Late Cretaceous (Maastrichtian) Deccan intertrappean deposits of peninsular India (Prasad et al., 2010). Adapisoriculids are also known from the Paleocene and Eocene of Europe and Africa (De Bast et al., 2013, Gheerbrant, 1995 and Gheerbrant and Russell, 1991). Taxa restricted to Africa include Garatherium, while those known only from Europe include Bustylus, Proremiculus and Remiculus. Still others, such as Adapisoriculus and Afrodon are common to Africa and Europe (De Bast et al., 2012, De Bast et al., 2013, Gheerbrant, 1988, Gheerbrant, 1991, Gheerbrant, 1995, Gheerbrant et al., 1998, Gheerbrant and Russell, 1989 and Gheerbrant and Russell, 1991; also refer Table 1, Fig. 1 and Fig. 2, present study).

Though possible euarchonton affinities have been suggested for adapisoriculids based on tarsal bone morphology (Boyer et al., 2010, Prasad and Godinot, 1994 and Smith et al., 2010), phylogenetic analysis of combined dental and tarsal characters demonstrated that adapisoriculids are basal eutherians and that Deccanolestes, the oldest known adapisoriculid, is a sister taxon of the Early Paleogene Afrodon from Africa (Goswami et al., 2011). Here we describe a new adapisoriculid from the same geographic region (peninsular India) that is known to yield the oldest record of this group (i.e., Deccanolestes). The new find reported here is approximately 10 million years younger in age than Deccanolestes.

 Locality and age

The material described in this paper comes from the North Pit of the Vastan Lignite Mine (21°25′47″N; 73°07′30″E) situated about 65 km northeast of the city of Surat and close (about 3 km) to a small village Nani Naroli in District Surat, Gujarat, western India (Fig. 3). Details of lithofacies and depositional environments are discussed in Prasad et al. (2013). Data on dinoflagellates, δ13C and 87Sr/86Sr (Clementz et al., 2011 and Garg et al., 2008), indicate an age of ∼54.5 Ma for the Vastan mammal fauna, including the new adapisoriculid described in this paper.

 Institutional abbreviations

Institutional abbreviations: (IITR) Department of Earth Sciences, Indian Institute of Technology Roorkee, Uttarakhand, India; (BSIP) Birbal Sahni Institute of Palaeosciences, Lucknow, Uttar Pradesh, India; (VPL/JU/) Vertebrate Palaeontology Laboratory, Department of Geology, University of Jammu, Jammu and Kashmir, India; (DUGF): Vertebrate Palaeontology Laboratory, Department of Geology, University of Delhi, Delhi, India; MNHN: Muséum national d’histoire naturelle, Paris, France.

 Methods and repository

The dentary (VLM-804) described in this paper was photographed using Field Emission Scanning Electron Microscope (FESEM Model: JEOL 7610F) at BSIP, Lucknow. Measurements of the dentition (Figs. 4A and B) were taken using a camera mounted stereoscopic microscope with Leica Application Suite software (Leica LAS V4.8). The Deccanolestes dentary (DUGF/IM/1) illustrated in this paper was photographed by X-ray Computed Tomographic (CT) imaging at the AST-RX platform of the MNHN, Paris using a GE Sensing and Inspection Technologies phoenix x-ray-v-tome-x L240-180 CT scanner. A microfocus RX source 240 kV/320 W, detector 400 × 400 mm with a matrix of 2024 pixels (pixel size: 200 × 200 μm) was used. Further, data reconstruction was carried out using datos-x reconstruction software (Phoenix-x-ray, release 2.0) and then exported into a 16-bit TIFF image stack. Finally, the 3D models were reconstructed from the CT scans using the computer programs Materialise Mimics Innovation Suite 18.0 Research Edition (× 64) and Maxon Cinema 4DR15.

The phylogenetic analysis was performed by Tree analysis using New Technology (TNT) software (Goloboff et al., 2008).

The material described here is catalogued in the Vertebrate Palaeontology Laboratory, Department of Earth Sciences, Indian Institute of Technology Roorkee, Uttarakhand under the acronym IITR/SB/VLM.

 Systematic palaeontology

Class: Mammalia Linnaeus, 1758

Infraclass: Eutheria Gill, 1872

Order: Insertae sedis

Family: Adapisoriculidae Van Valen, 1967

Genus: Indolestes gen. nov.

Type and only species: Indolestes kalamensis gen. et sp. nov.

Derivation of name: The genus name is the combination of “Indo” for India and “lestes”, a common suffix used for insectivorous mammals.

Diagnosis: A large adapisoriculid having the following features: double rooted p3 and p4; diastema between p3 and p4; mental foramen below p3; p4 with a small but distinct paraconid positioned anterolingual to the large protoconid; p4 metaconid absent; labiolingually compressed p4 protoconid; molar (m2 and m3) trigonid slightly wider than talonid, molar trigonid height almost twice the talonid height; lingual cusps in molars in line with each other, molar talonids with three cusps (entoconid, hypoconid and hypoconulid) with a highly salient hypoconid, positioned labially while hypoconulid positioned close to the entoconid; entoconid slightly more developed than hypoconulid; cristid obliqua moderately developed in molars (m2–m3), labial to the protocristid notch and ascends slightly on the posterior trigonid wall.

Differential diagnosis: Indolestes preserves large molars compared to well-known adapisoriculid genera (Deccanolestes, Afrodon and Bustylus). Indolestes molars differ from those of Deccanolestes (D. hislopi, D. robustus) and all known species of Bustylus in having molars with slightly wider trigonid than talonid. Further, differ from those of Deccanolestes (D. hislopi, D. robustus), Afrodon (A. chleuhi) and Bustylus in having a prominent hypoconid, and from those of Afrodon (A. gheerbranti), Bustylus and Adapisoriculus (A. minimus) in lacking a p4 metaconid.

Age: early Eocene of India

Indolestes kalamensis sp. nov. (Fig. 5 and Fig. 6)

Holotype: IITR/SB/VLM-804 (right dentary with alveoli for p2, p3 and m1; crowns for p4, m2 and m3 in place).

Derivation of name: The species is named in honor of late Dr. A.P.J. Abdul Kalam, former Indian president for his iconic contributions as an inspirational role model in science and technology in India.

Diagnosis: Same as for the genus

Type Locality: Vastan Lignite Mine, Taluka Mangrol, District Surat, Gujarat state, western India.

Type Horizon: Cambay Shale (early Eocene, ∼54–55 Ma)

Description: The holotype is a right mandible preserving alveoli for p2, p3 and m1; in situ crowns for p4, m2 and m3. The only preserved mental foramen is observed at a depth of 0.89 mm below p3. The horizontal ramus is deep, ventrally convex with the greatest depth below the m2–m3 junction (see Table 2 for measurements). The ramus is convex lingually but nearly flat labially. The masseteric fossa is shallow. The coronoid process slopes upward at an angle of about 45° (Fig. 5A–C).

Although the alveoli anterior to p3 are damaged and do not preserve the bony partition (interalveolar septa), the bifurcated dorsal outline suggests that p2 was double-rooted, similar to p3-m3 (inferred from alveoli in the case of p3 and m1). A 0.62-mm diastema is observed between p3 and p4 (Fig. 5A1 and A2).

p4 is larger than p3 (as indicated by the size of alveoli) and is anteroposteriorly elongated, measuring 1.97 mm in length and 0.95 mm in width. A low but distinct paraconid is present anteriolingual to the protoconid. The protoconid is high and labiolingually compressed. The posterolingual portion of this tooth is damaged and a weak crest descends posterolingually from the protoconid towards this damaged region (Fig. 5A1 and A2; Fig. 6G–I).

Molars are robust and obliquely set in the dentary. Detailed measurements of the in situ molars in the holotype dentary are provided in Table 3.

The m2 trigonid is shorter as compared to the talonid and also about twice as high as the talonid. The trigonid is slightly wider than the talonid. An anterobuccal cingulid (precingulid) is seen to extend from the base of the paraconid to the base of the protoconid but no cusp is discernable. An anteriorly canted paraconid is positioned anteriolabial to the metaconid. Both these cusps are separated at their bases resulting in a lingual opening in the trigonid basin. The lingual cusps are in line with each other. The protoconid is the largest and the highest cusp, followed by metaconid and paraconid, respectively. The protoconid is labially convex. The metaconid is situated slightly posterolingual to the protoconid, resulting in obliquity of the posterior trigonid wall with respect to the transverse axis. The protolophid joining the protoconid and metaconid is notched (this feature is better observed in m3). The moderately developed cristid obliqua slightly ascends the trigonid wall but stays buccal to the protocristid notch thereby creating a wider talonid basin. The hypoflexid is deep. All three talonid cusps are better developed in m2 than in m3. Post-cingulid, labial cingulid and lingual cingulid are lacking. On the talonid, the hypoconid is the largest cusp, followed by the entoconid and hypoconulid. The hypoconid is labially positioned, thereby creating a deep and broad talonid basin. The posterolingually positioned hypoconulid is closer to the entoconid than to the hypoconid. Wear facets are best observed on this molar (for terminologies refer to Crompton and Kielan-Jaworowska, 1978). The narrow wear facet 1 is developed parallel to the posterior trigonid wall and lies along the ridge connecting the high protoconid and a slightly lower metaconid. However, this wear facet is disconnected at the protoconid-metaconid notch. Wear facet 2 extends posterolabially from the paraconid towards the protoconid. Wear facet 3 extends from the top of the hypoconid along the cristid obliqua while wear facet 4 extends posterolingually from the hypoconid ending well short of the hypoconulid. Wear facet 5 is not clearly observed but facet 6 is observed at the position of the posterolingual cusps (refer section 6 “Comparisons” and Fig. 9).

The m3 is broadly similar in crown morphology to m2 but smaller in size. The trigonid is less than twice the height of the talonid in this tooth (see Table 3). The apex of the paraconid is broken off but is anteriorly canted. The m3 talonid is narrower than that in m2 since the hypoconid is positioned less labially compared to that in m2. Compared to the condition in m2, the hypoconulid in m3 projects more posteriorly (although still close to the entoconid). The entoconid is smaller than in m2 and also labiolingually compressed. The wear pattern in m3 resembles that of m2 but is less prominent.

 Comparisons

Comparison of Indolestes with possible lipotyphlans or proteutherians known from the Early Paleogene of the Indian Subcontinent reveals important differences. The p4 of Pakilestes lathrius from the middle Eocene Kuldana Formation of Pakistan (Russell and Gingerich, 1981) is 46% smaller and its protoconid is markedly convex labially and the tooth has a short, narrow and basined talonid, unlike the p4 of Indolestes. The Pakislestes molar (m1/m2) is about 60% smaller in size, with the paraconid projecting more anteriorly than in Indolestes. Seia shahi from Kohat region of Pakistan (Russell and Gingerich, 1981) is known from isolated upper molars (M1 and M2), therefore, direct morphological comparison with I. kalamensis is currently not possible. Perizalambdodon, described as a lipotyphalan by Thewissen et al. (2005) on the basis of an isolated lower molar (m1 or m2, H-GSP 92168) has a smaller m2 (about 80%) and lacks an entoconid and a talonid basin.

Previously described early Eocene insectivores from Vastan include an erinaceomorph Vastania sahnia, a palaeoryctid Anthraryctes vastanensis and a cimolestid Suratilestes gingerichi (Bajpai et al., 2005). Indolestes was also recovered from the same horizon at Vastan. Vastania can be easily distinguished from Indolestes in lacking a diastema between p3 and p4, having a smaller p4 (about 50%), a smaller m2 (about 60%) and a smaller m3 that lacks an entoconid. Suratilestes, described as a cimolestid, can also be clearly distinguished from Indolestes in having smaller (by about 60%) p4 without a paraconid, relatively smaller molars (m2 about 60% smaller and m3 about 54% smaller) with large difference in height between trigonid and talonid and having a wider talonid than trigonid. Anthraryctes, known from an isolated upper molar (M3) and the only record of a palaeoryctid from the early Eocene of India, cannot be directly compared with Indolestes.

Overall, the lower dentition (p4, m2 and m3) of I. kalamensis is reminiscent of the family Adapisoriculidae in exhibiting the following characters: mental foramen below p3 in the dentary, presence of a strong paraconid positioned anterolabially on the trigonid, a salient hypoconid positioned labially on the talonid, the hypoconulid shifted lingually close to the entoconid and a moderately developed cristid obliqua that ascends slightly on the posterior trigonid wall. Also, consistent with its younger stratigraphic record, Indolestes displays several characters that are derived relative to the oldest known adapisoroculid (Deccanolestes) and Paleocene taxa known from Africa (Afrodon chleuhi, Afrodon gheerbranti). These characters include larger size of lower molars with a talonid slightly less wide than the trigonid; deep and ventrally convex ramus; diastema between p3 and p4; m3 < m2 and cristid obliqua positioned slightly labial to the protoconid-metaconid notch.

I. kalamensis is a large adapisoriculid when compared to well-known adapisoriculids from India, Africa and Europe (e.g. Deccanolestes, Afrodon and Bustylus), with m2 size (length × width) approximately 30% larger than A. gheerbranti, 66% larger than Bustylus marandati, 58% larger than Bustylus folieae; m3 about 72% larger than Deccanolestes narmadensis, 68% larger than Deccanolestes cf. hislopi (isolated m3 ITV/R/Mm-12), 16% larger than A. gheerbranti, 47% larger than Afrodon germanicus, 68% larger than B. marandati and approximately 49% larger than A. chleuhi and B. folieae. Table 4 provides measurements of the lower dentition (p4-m3) of few known adapisoriculids while Fig. 7 provides a bivariate plot showing size comparisons between Indolestes and previously known adapisoriculids.

Molars of I. kalamensis were directly compared with the original specimens of Late Cretaceous Indian species D. narmadensis (VPL/JU/IM/6, VPL/JU/IM/7 and the holotype VPL/JU/IM/8) that is known only from lower molars. The two species are broadly similar in having lingual cusps in line with each other and the trigonid cusps forming an open triangle. However, Indolestes molars are more derived than those of D. narmadensis in having a slightly wider trigonid than the talonid; hypoconulid shifted lingually close to the entoconid and having a cristid obliqua positioned slightly labial to the protoconid-metaconid notch that ascends the posterior trigonid wall. It should be noted that the mandible fragments of adapisoriculids with in situ dentition are uncommon in the fossil record, making comparisons within the group difficult. Interestingly, the Late Cretaceous intertrappean locality at Naskal (South India), known for producing many isolated upper and lower teeth of Deccanolestes (Prasad and Sahni, 1988, Prasad et al., 1994 and Prasad et al., 2010), recently yielded a mandible fragment (DUGF/IM/1) with in situ p3, p4, m1 and m2 (Fig. 8A–C). This specimen is illustrated here for purposes of comparison (for measurements of dentition, refer to Table 4). The preserved dentary (DUGF/IM/1) referred here to Deccanolestes hislopi, is similar to Indolestes in the following characters: presence of a deep and ventrally convex ramus; lingually open molar trigonids; presence of a precingulid, protoconid being the largest cusp on trigonid; having a metaconid and protoconid that are separated at the base with the metaconid situated slightly posterolingual to the protoconid resulting in obliquity of the posterior trigonid wall with respect to the transverse axis. However, apart from being smaller in size, DUGF/IM/1 differs from Indolestes in the presence of a conspicuous diastema between p2 and p3, presence of a mental foramen below p4-m1 junction, having a ramus that is concave labially and convex lingually with greatest depth below m1-m2 junction. The not so well preserved p4 in DUGF/IM/1 has a large talonid unlike Indolestes. The molars of D. hislopi (DUGF/IM/1) are quite smaller (m2 about 69% smaller) compared to Indolestes and can be clearly differentiated from the latter in the presence of a trigonid as wide as talonid; a crest like paraconid; cristid obliqua joining the posterior trigonid wall lingually and hypoconulid median in position.

Another taxon, Sahnitherium rangapurensis, was described from the Late Cretaceous intertrappean deposits of Rangapur, South India (Rana and Wilson, 2003), a locality about 4 km southeast of the famous mammal-yielding locality Naskal that yielded the first Cretaceous mammal of India i.e. Deccanolestes. Sahnitherium (known only from an isolated right upper molar, M1 or M2) is morphologically very close to the upper molars of Deccanolestes and detailed phylogenetic analysis suggests that this upper molar belongs to an adapisoriculid (Goswami et al., 2011). As Indolestes is known only from lower dentition, direct morphological comparisons with Sahnitherium cannot be made at this stage, however, Indolestes molar (m2) is larger (by about 56%) compared to the upper molar (specimen no. ITV/R/Mm-1) known for Sahnitherium.

The genus Afrodon can be clearly differentiated from Indolestes in having a submedian hypoconulid and cristid obliqua extending onto the lingual region of the posterior wall of the trigonid. A. gheerbranti differs from Indolestes in having smaller molars, a talonid as wide as trigonid, medially positioned hypoconulid, less salient hypoconid and presence of a p4 metaconid.

Molars of Bustylus are morphologically similar to Indolestes in the presence of a closely-spaced entoconid and hypoconulid. However, the latter differs in size (as discussed earlier) and in having a slightly larger hypoconid compared to the entoconid. Moreover, the genus Bustylus is typified based on the morphology of p4 that depicts a large paraconid, small and well-individualized metaconid (De Bast et al., 2013), unlike the p4 of Indolestes. A well-preserved dentary of Bustylus (B. germanicus) preserving a partial alveolus for c1, complete alveolus for p1, alveoli for biradiculate p2–p3 and in situ p4–m3, was recently reported from Maret, Belgium (Specimen no. IRSNB M2017, De Bast et al., 2013, Fig. 3G–K) and shows no diastema between the teeth, unlike in Indolestes.

Adapisoriculus (A. minimus) differs from Indolestes in being smaller (discussed earlier), having a p4 metaconid and in having molars that have a trigonid as wide as the talonid with a metaconid slightly more developed than the protoconid.

Garatherium is known from the late Paleocene and early Eocene of Africa (Crochet, 1984, Gheerbrant, 1988, Gheerbrant, 1995 and Gheerbrant et al., 1998). However, this genus is known only by isolated upper dentition and thus, cannot be directly compared with Indolestes at this stage.

The molars in the European adapisoriculid genus Remiculus (Russell, 1964 and Smith, 1997) have a significantly broader talonid than trigonid and a metaconid that is better developed than the protoconid, as opposed to that of Indolestes.

Proremiculus (P. lagnauxi) from the early Paleocene of Europe is known from isolated upper and lower molars (De Bast et al., 2012). The lower molars in this taxon are smaller (in size), have a wider talonid than the trigonid with three equidistant talonid cusps (hypoconulid median in position) and a hypoflexid that is shallow and wide.

Furthermore, it is observed that the position and pattern of wear facets (in particular 1, 2, 3, 4, 6) in the lower molar (m2) of Indolestes are similar to those generally found in the molars (m1–m2) of known adapisoriculids (see Fig. 9 of this article; also see Fig. 6 of De Bast et al., 2012). Facets 1 and 2 are the principal shearing surfaces on the trigonid. Facet 1 is better developed in Indolestes compared to Deccanolestes and Afrodon, but is less prominent compared to that in Bustylus. The wear pattern and morphology of the talonid (facets 3, 4 and 6) suggests that the talonid ‘pestle’ and protocone ‘mortar’ were used as a puncturing mechanism during feeding (sensu Luo, 2007), but this mechanism was less well developed in Indolestes compared to Bustylus and Adapisoriculus. In addition, the talonid morphology in Indolestes indicates that the upper molars of Indolestes should reveal a wider upper embrasure between the widely separated paracone and metacone (dilambdodonty) and a high and large protocone (generally observed in upper molars of adapisoriculids). The presence of a prominent precingulid in Indolestes and other known adapisoriculids (e.g., Deccanolestes) guarded the gum region from the metacone during shearing of food (sensu Crompton and Kielan-Jaworowska, 1978). Overall, the wear pattern and the tooth morphology of Indolestes are reminiscent of an adaptation for both shearing and puncturing of food. A detailed study on this aspect is beyond the scope of this paper, but will be taken up separately in the future.

 Phylogenetic analysis

To assess the position of I. kalamensis, a preliminary phylogenetic analysis was conducted by adding this new taxon to the recently published matrix of De Bast et al. (2013) that includes the known Cretaceous–Paleogene (K–Pg) adapisoriculid taxa from India, Africa and Europe. De Bast et al. (2013) analysis is a simplified version of a previous analysis (De Bast et al., 2012) and excludes certain less well-known taxa (D. narmadensis, Afrodon ivani and A. tagourtensis). De Bast et al. (2013) also excluded Remiculus citing “possible convergences” with Adapisoriculus. In the present study, phylogenetic analysis was performed using Tree analysis using New Technology (TNT) software (Goloboff et al., 2008). The final matrix includes 12 taxa and 16 dental characters. A total of six dental characters based on lower dentition (IITR/SB/VLM-804) could be scored for Indolestes. “New Technology Search” function was run initially with the option to stabilize the consensus five times and setting the maximum branch length to 0 (i.e., collapsing rule 3). Subsequently, a “Traditional Search” with Tree Bisection and Reconnection (TBR) option was run, utilizing the trees produced in the previous search. The TNT software found eight Most Parsimonious Trees (MPTs) of Tree Length (TL) 22. The Consistency Index (CI) is 0.909 and the Retention Index (RI) is 0.949. The Strict Consensus tree is shown in Fig. 10. The character states for Indolestes are provided in Table 5 and details of these characters can be found in Appendix 1 of De Bast et al. (2013).

Overall, the results are in agreement with previous studies that suggest (a) Deccanolestes and Afrodon are primitive members of the family Adapisoriculidae, (b) Bustylus germanicus (= Afrodon germanicus) is more derived than other species of the genus Afrodon, (c) Bustylus germanicus is sister to the clade formed by Adapisoriculus minimus and all species of Bustylus. Our results suggest that Indolestes is more derived than Deccanolestes (D. hislopi and D. robustus) and Afrodon (A. chleuhi and A. gheerbranti) possibly due to the presence of a larger hypoconid as compared to entoconid (Character 9:1) and closer placement of molar hypoconulid and entoconid (Character 10:1). It is important to note that whereas both A. chleuhi and I. kalamensis gen. et sp. nov. have narrower molar talonids (than trigonid) (Character 11:0), this character is not shared by the clade formed by Bustylus (B. germanicus, B. cernaysi, B. marandati, B. folieae) and A. minimus. The presence of a p4 metaconid in the latter clade is another character (Character 14:0) that suggests that this clade is more derived than Indolestes. In addition, the presence of several additional characters, such as a hypoconid slightly larger than entoconid (Character 9:1); hypoconulid positioned closer to the entoconid (Character 10:1); small size of p4 paraconid (Character 16:1) suggests a primitive dental morphology of Indolestes compared to European A. minimus.

It is to be noted that in all the eight MPTs produced, the position of Indolestes remains the same. Of the three hypotheses considered in the eight MPTs, for the phylogenetic relationships among Indolestes, Deccanolestes, Afrodon, Bustylus and Adapisoriculus, the first hypothesis suggests A. chleuhi is the most basal adapisoriculid and sister to the unresolved clade formed by A. gheerbranti + Deccanolestes hislopi + D. robustus. This unresolved clade is sister group to Indolestes + (Bustylus + Adapisoriculus) (Fig. 11A). The second hypothesis indicates Deccanolestes, Indolestes and Bustylus form successive sister taxa lineages to Adapisoriculus while Afrodon is the most basal adapisoriculid (Fig. 11B). The third hypothesis suggests that Afrodon + Deccanolestes are basal adapisoriculids and form an unresolved clade. This unresolved clade is sister group to Indolestes and (Bustylus + Adapisoriculus) (Fig. 11C). We favor the third hypothesis, as it matches better the stratigraphic position of Deccanolestes. However, the phylogenetic results presented here are tentative as the analysis is based only on dental characters and only 37% (6 out of 16) characters could be scored for Indolestes. Additional and more complete material (especially upper dentition and post-cranial elements) will help resolve the phylogenetic position of Indolestes among adapisoriculids with greater certainty.

 Discussion

I. kalamensis gen. et sp. nov. adds significantly to the diversity of insectivores from Vastan as it represents a family hitherto not known from the Eocene of the Indian Subcontinent. Its lower dental morphology and wear facets are reminiscent of the family Adapisoriculidae and exhibit a pattern that played a role in both shearing and puncturing of food during feeding (Fig. 9). Indolestes is distinguishable from previously described Eocene insectivores from the Indian subcontinent including those known from Vastan (Bajpai et al., 2005).

Various proposals have been put forward with regard to the geographic region of origin of Adapisoriculidae. An African origin was proposed due to the presence of A. chleuhi (a primitive adapisoriculid) in the Paleocene of this region and a long history of this group in the erstwhile Gondwana (Gheerbrant and Russell, 1989) while a European origin for this family was suggested due to the presence of a highly diverse Paleocene adapisoriculid fauna in this region (De Bast et al., 2012). It should be noted that no adapisoriculids are known from the much explored European Cretaceous. However, De Bast et al. (2012) suggested that the high diversity of European adapisoriculids is an indication of the presence of a still unknown adapisoriculid clade in the Cretaceous of Europe that may have led to a Deccanolestes- and Afrodon-like taxa that eventually migrated to India (during the Cretaceous) and to Africa (during Paleocene), respectively. In another explanation, the high diversity of adapisoriculids in the Paleocene of Europe and the presence of Afrodon in both Europe and northern Africa were attributed to migrations between these continents around the K–Pg boundary (Smith et al., 2010).

Recent data has shown that an Indian origin of adapisoriculids is more likely since the oldest (Late Cretaceous) stratigraphic record of adapisoriculids (Deccanolestes) is known from this region (Goswami et al., 2011, Prasad et al., 2010 and Smith et al., 2010). Phylogenetic analysis shows that Deccanolestes is a sister taxon to Afrodon indicating an Out-of-India migration towards Africa and/or Europe (Goswami et al., 2011 and Prasad et al., 2010). Goswami et al. (2011) have also suggested that adapisoriculids are part of a clade consisting of the basal eutherians and that a “ghost lineage” for adapisoriculids was present in the Gondwana for at least ∼30 million years before Deccanolestes.

The discovery of Indolestes suggests continuation of the adapisoriculid lineage for more than 10 million years, after the Deccan volcanic episode during the terminal Cretaceous-earliest Paleocene. Also, Indolestes represents the first evidence for the presence of a mammal of Gondwanan lineage in the early Eocene of India. The primitive dental morphology of Indolestes relative to the European taxa (Bustylus and Adapisoriculus) weakens the possibility of India's biogeographic connection with Europe (in so far as the adapisoriculids are concerned). However, given the rich fossil record of adapisoriculids in the Paleocene of Africa and Europe, and the derived dental morphology of Indolestes relative to Afrodon, an in-to-India dispersal event during the Paleocene cannot be currently ruled out. The discovery of Paleocene mammals in India will help test this hypothesis. Prasad and Sahni (1999) suggested that, given the small size of these mammals, a trans-oceanic dispersal (sweepstakes) may have allowed faunal exchanges between India and Eurasia during the Late Cretaceous (∼65 Ma). More recently, however, it has been proposed (Chatterjee and Bajpai, 2016, Chatterjee and Scotese, 2010 and Chatterjee et al., 2013) that an island arc system (Oman-Kohistan-Dras) that existed north of the Indian Subcontinent during the Late Cretaceous acted as ‘stepping stones’ between India and Africa to facilitate faunal interchanges between these landmasses (Fig. 12). It is plausible that adapisoriculids may have used this migration route, as also suggested by Prasad et al. (2010). However, this hypothesis also needs to be tested rigorously, since the timing of contact between the Oman-Kohistan-Dras Island arc and the Indian plate is controversial, with several recent workers (e.g., Bouilhol et al., 2013 and Jagoutz et al., 2015) favoring a much younger (∼50 Ma) age for this contact.

Future discoveries from the Early Cretaceous interval of erstwhile Gondwanan and/or Laurasian continents and from the Paleocene of India will likely allow a better understanding of the phylogenetic relationships as well as paleobiogeographic reconstructions involving this interesting family of mammals that survived the K–Pg boundary events including the Deccan volcanic activity.

 Acknowledgements

This work is supported by the Department of Science and Technology (DST), Government of India in the form of Young Scientist Fast Track Project (SR/FTP/ES-49/2012) grant to V.V.K. V.V.K. would like to acknowledge Prof. Christopher R. Scotese (Director, PALEOMAP Project, Illinois, USA), Prof. Escarguel Gilles (Editor in chief, Geobios) and Elsevier (license nos. 3943651202321 and 3945261204604) for granting permission(s) to reuse and redraw illustrations. Research Development and Co-ordination Cell (RDCC), BSIP, Lucknow is also thankfully acknowledged (Permission no. BSIP/RDCC/Publication no. 43/2015). VVK also acknowledges Brian D. Rankin (Museum of Palaeontology, University of California) for sharing his opinion and discussions on early Cenozoic insectivorous mammals. GVRP acknowledges the financial support from J.C. Bose National Fellowship (SR/S2/JCB-14/2010). GVRP also acknowledges Miguel Gorda Sanz and Florent Gossard of MNHN, Paris, France for CT Scans of Deccanolestes hislopi. Authors (V.V.K., D.P.D., S.B.) would like to sincerely thank Gujarat Industries Power Company Limited (GIPCL) for necessary permission(s) and staff members of the Vastan Lignite Mine, Gujarat for extending logistic support during field excursions and help in many other ways. The authors also acknowledge anonymous reviewers and the Associate Editor whose constructive comments helped in improving the quality of the manuscript.

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Palaeogeographic map close to the K–Pg interval, showing localities yielding known adapisoriculid genera from across the globe as well as the present locality (Vastan, India) that yielded Indolestes. (1) Naskal (India), (2) Kisalpuri (India), (3) Hainin (Belgium), (4) Walbeck (Germany), (5) Cernay (France), (6) Adrar-Mgorn (Morocco), (7) Dormaal (Belgium) and (8) Vastan (India). Note: filled circles Green, Late Cretaceous; Yellow, early Paleocene; Blue, late Paleocene; Red, early Eocene. Map modified after Scotese (2006) with permission.

Carte paléogéographique proche de l’intervalle K–Pg, montrant les localités qui ont fourni des genres d’adapisoriculidés connus à travers le globe et dans la présente localité (Vastan, Inde) qui a fourni Indolestes. (1) Naskal (Inde), (2) Kisalpiuri (Inde), (3) Hainin (Belgique), (4) Walbeck (Allemagne), (5) Cernay (France), (6) Adrar-Mgorn (Maroc), (7) Dormaal (Belgique) et (8) Vastan (Inde). À noter : cercles pleins vert, Crétacé supérieur ; jaune, Paléocène inférieur ; bleu, Paléocène supérieur ; rouge, Éocène inférieur. Carte modifiée d’après Scotese (2006), avec son autorisation.

Temporal range of known adapisoriculids from India, Africa and Europe. A: Afrodon; Ad: Adapisoriculus; B: Bustylus; D: Deccanolestes; G: Garatherium; I: Indolestes; P: Proremiculus; R: Remiculus.

Domaine temporel des adapisoriculidés connus en Inde, Afrique et Europe. A : Afrodon ; Ad : Adapisoriculus ; B : Bustylus ; D : Deccanolestes ; G : Garatherium ; I : Indolestes ; P : Proremiculus ; R : Remiculus.

Location map showing position of the fossil locality (Vastan, District Surat, Gujarat, western India) with a lithostratigraphic section showing Indolestes kalamensis gen. et sp. nov. yielding level. Note: ETM2 level is marked (red arrow) about 20 m above the mammalian level.

Carte de localisation montrant la position de la localité fossilifère (Vastan, District de Surat, Gujarat, Inde occidentale) avec une section lithostratigraphique, avec un niveau à Indolestes kalamensis gen. et sp. nov. À noter que le niveau EDTM2 est marqué environ 20 m au-dessus du niveau à mammifères.

A generalized sketch of the lower molar. A. Occlusal aspect. B. Lateral aspect. Pad: paraconid; Metd: metaconid; Prtd: protoconid; Entd: entoconid; Hypld: hypoconulid; Hypd: hypoconid; TaB: talonid basin; TrB: trigonid basin; TaWd: talonid width; TrWd: trigonid width; TaLn: talonid length; TaHt: talonid height; TrHt: trigonid height. Modified after Gheerbrant and Russell, 1991.

Schéma général de la molaire inférieure. A. Aspect occlusal. B. Aspect latéral. Pad : paraconide ; Metd : métaconide ; Prtd : protoconide ; Entd : entoconide ; Hypld : hypoconulide ; Hypd : hypoconide ; TaB : bassin du talonide ; TrB : bassin du trigonide ; TaWd : largeur du talonide ; TrWd : largeur du trigonide ; TaLn : longueur du talonide ; TaHt : hauteur du talonide ; TrHt : hauteur du trigonide. Modifié d’après Gheerbrant et Russell, 1991.

Indolestes kalamensis gen. et sp. nov. (IITR/SB/VLM-804, holotype, right dentary with in situ p4, m2–m3): (A1) occlusal view; (A2) close-up view in occlusal aspect showing alveoli in front of p4; (B) labial view; (C) lingual view.

Indolestes kalamensis gen. et sp. nov. (IITR/SB/VLM-804, holotype, dentaire droit avec p4, m2–m3 in situ) : (A1) vue occlusale ; (A2) gros plan en vue occlusale montrant des alvéoles en avant de p4 ; (B) vue labiale ; (C) vue linguale.

Indolestes kalamensis gen. et sp. nov. (IITR/SB/VLM-804, holotype). (A) m3, occlusal view; (B) m3, lingual view; (C) m3, labial view; (D) m2, occlusal view; (E) m2, lingual view; (F) m2, labial view; (G) p4, occlusal view; (H) p4, lingual view; (I) p4, labial view. Scale bar equals 300 μm for all.

Indolestes kalamensis gen et sp. nov. (IITR/SB/VLM-804, holotype. (A) m3, vue occlusale ; (B) m3, vue linguale ; (C) m3, vue labiale ; (D) m2, vue occlusale ; (E) m2, vue linguale ; (F) m2, vue labiale ; (G) p4, vue occlusale ; (H) p4, vue linguale ; (I) p4, vue labiale. La barre d’échelle représente 300 μm pour tous.

Bivariate plot showing size variations in the lower dentition (ultimate premolar and lower molars) between Indolestes kalamensis gen. et sp. nov. from the early Eocene of India and well-recognized adapisoriculids from India, Africa and Europe based on data provided in Table 4 of this article. Note: a: Isolated lower molars identified by previous workers as “m1 or m2” for Deccanolestes narmadensis, Deccanolestes cf. hislopi, Proremiculus lagnauxi and Remiculus deutschi have been considered as m1 for plotting purpose only; b: p4 (triangle), m1 (square), m2 (diamond) and m3 (circle). Data on measurements compiled from De Bast et al., 2012, De Bast et al., 2013, Gheerbrant, 1988, Gheerbrant, 1991, Gheerbrant, 1993, Gheerbrant, 1995, Gheerbrant and Russell, 1989, Gheerbrant and Russell, 1991, Prasad and Sahni, 1988, Prasad et al., 1994 and Prasad et al., 2010.

Report graphique à double entrée montrant les variations de taille dans la dentition inférieure (dernière prémolaire et molaires inférieures) entre Indolestes kalamensis gen.et sp. nov. de l’Éocène inférieur d’Inde et les adapisoriculidés d’Inde, d’Afrique et d’Europe, basé sur des données fournies dans le Tableau 4 de cet article. À noter : a : les molaires inférieures isolées identifiées par des chercheurs antérieurs comme « m1 ou m2 » pour Deccanolestes narmadensis, Deccanolestes cf. hislopi, Proremiculus lagnauxi et Remiculus deutschi ont été considérées comme m1 uniquement dans un but de report graphique ; b : p4 (triangle), m1 (carré), m2 (losange) et m3 (cercle). Données sur les mesures compilées d’après De Bast et al., 2012 and De Bast et al., 2013 ; Gheerbrant, 1988, Gheerbrant, 1991 and Gheerbrant, 1995 ; Gheerbrant and Russell, 1989 and Gheerbrant and Russell, 1991 ; Prasad et Sahni, 1988 ; Prasad et al., 1994 and Prasad et al., 2010.

CT images of Deccanolestes hislopi (DUGF/IM/1, left dentary with p3–m2). (A) labial view; (B) occlusal view; (C) lingual view.

Images CT de Deccanolestes hislopi (DUGF/IM/1, dentaire gauche, avec p3-m2). Vues labiale (A), occlusale (B), linguale (C).

A diagrammatic sketch of lower molars (m1–2) of known adapisoriculids showing wear facets: 1 (orange), 2 (red), 3 (yellow), 4 (blue), and 6 (green). (A–B) Deccanolestes narmadensis (right m1 or m2, VPL/JU/IM/7); (C–D) Afrodon chleuhi (left m1?, THR 214); (E–F) Indolestes kalamensis gen. et sp. nov (right m2, IITR/SB/VLM-804); (G–H). Bustylus cernaysi (right m1, CR 361 SLP); (I–J) Adapisoriculus minimus (right m2, Cr 301 Bn). Terminology of the wear facets follows Crompton and Kielan-Jaworowska (1978). For measurement scales of figures C, D, G, H, I and J refer Gheerbrant and Russell, 1989 and Gheerbrant and Russell, 1991. Figures reused and redrawn from Gheerbrant and Russell, 1989 and Gheerbrant and Russell, 1991 and Prasad et al. (2010) with permission from Elsevier.

Schémas des molaires inférieures (m1–2) d’adapisoriculés connus, montrant des facettes d’usure : 1 (orange), 2 (rouge), 3 (jaune), 4 (bleu) et 6 (vert). (A–B) Deccanolestes narmadensis (m1 ou m2 droite, VPL/JU/DM/7) ; (C–D) Afrodon chleuhi (m1 ? gauche, THR 214) ; (E–F) Indolestes kalamensis gen. et sp. nov. (m2 droite, IITR/SB/VLM-804) ; (G–H) Bustilus cernaysi (m1 droite CR 361 SLP) ; (I–J) Adapisoriculus minimus (m2 droite, CR 301 Bn). La terminologie des facettes d’usure suit Crompton et Kielan-Jaworowska (1978). Pour les échelles des figures C, D, H, I et J, se référer à Gheerbrant et Russell (1989, 1991). Les figures réutilisées et redessinées sont issues de Gheerbrant and Russell, 1989 and Gheerbrant and Russell, 1991 et de Prasad et al. (2010), avec l’autorisation d’Elsevier.

Strict consensus tree of 8 maximum parsimonious trees (MPTs) with geographic affinities of the adapisoriculids used in the phylogenetic analysis. Synapomorphic characters are displayed at each node.

Arbre de strict consensus de 8 arbres de parcimonie maximum (MPT), avec les affinités des adapisoriculidés utilisés dans l’analyse phylogénétique. Les caractères synapomorphiques sont indiqués à chaque nœud.

Three different hypotheses of phylogenetic relationships among Deccanolestes, Afrodon, Bustylus, Adapisoriculus and Indolestes based on eight maximum parsimonious trees (MPTs).

Trois hypothèses différentes de relations phylogénétiques entre Deccanolestes, Afrodon, Bustylus, Adapisoriculus et Indolestes, basées sur huit arbres de parcimonie maximum (MPT).

Palaeogeographic map showing biotic exchanges between India and its surrounding landmasses involving adapisoriculids around the K–Pg interval. Indolestes yielding locality (Vastan) marked by a star. Mdr: Madagascar; Ker: Kerguelen. Map modified after Chatterjee and Scotese (2010) with permission.

Carte paléogéographique montrant les échanges biotiques entre l’Inde et ses masses continentales environnantes incluant des adapisoriculidés autour de l’intervalle K–Pg. La localité fournissant Indolestes (Vastan) est marquée d’une étoile. Mdr : Madagascar ; Ker : Kerguelen. Carte modifiée d’après Chatterjee et Scotese (2013) avec l’autorisation des auteurs.

List of known adapisoriculids.

Liste des adapisoriculidés.

Table 1 Taxon Locality Geographic area Age Author(s) Deccanolestes hislopi Naskal, India Indian Subcontinent Late Cretaceous (Maastrichtian) Prasad and Sahni, 1988 Deccanolestes robustus Naskal, India Indian Subcontinent Late Cretaceous (Maastrichtian) Prasad et al., 1994 Deccanolestes cf. hislopi Naskal, India Indian Subcontinent Late Cretaceous (Maastrichtian) Prasad et al., 1994 Deccanolestes narmadensis Kisalpuri, India Indian Subcontinent Late Cretaceous (Maastrichtian) Prasad et al., 2010 Afrodon chleuhi AdrarMgorn 1, Morocco Africa Late Paleocene Gheerbrant, 1988 Afrodon tagourtensis N’Tagourt 2, Morocco Africa Early Eocene Gheerbrant, 1993 Afrodon ivani Pyrenees, Spain Europe Late Paleocene López-Martínez and Peláez-Campomanes, 1999 Afrodon gheerbranti Hainin, Belgium Europe Early Paleocene (MP1-5) De Bast et al., 2012 Bustylus cernaysi Cernay, France Europe Late Paleocene Gheerbrant and Russell, 1991 Bustylus marandati Hainin, Belgium Europe Early Paleocene (MP1-5) Gheerbrant, 1991 Bustylus folieae Hainin, Belgium Europe Early Paleocene (MP1-5) De Bast et al., 2012 Bustylus marandati Hainin, Belgium Europe Early Paleocene (MP1-5) De Bast et al., 2012 Bustylus germanicus Walbeck, Germany Europe Late Paleocene De Bast et al., 2013 and Gheerbrant and Russell, 1989 Garatherium mahboubii El-Kohol, Algeria Africa Early Eocene Crochet, 1984 Proremiculus lagnauxi Hainin, Belgium Europe Early Paleocene (MP1-5) De Bast et al., 2012 Remiculus deutschi Walbeck, Germany Europe Late Paleocene Russell, 1964 Remiculus delsatei Dormaal, Belgium Europe Early Eocene Smith, 1997 Adapisoriculus minimus Cernay, France Europe Late Paleocene Lemoine, 1885 Indolestes kalamensis gen. et sp. nov. Vastan, India Indian Subcontinent Early Eocene Present study

Measurements (in mm) of the ramus depth in the dentary (IITR/SB/VLM-804) of Indolestes kalamensis gen. et sp. nov.

Mesures (en millimètres) de la profondeur du ramus dans le dentaire (IITR/SB/VLM-804) d’Indolestes kalamensis gen. et sp. nov.

Table 2 p1 p2 p3 p4 m1 m2 Depth below m2–m3 junction m3 IITR/SB/VLM-804 (holotype) – 1.55 a 1.94 2.91 3.32 3.57 3.62 3.50

Estimate.

Measurements (in mm) of molars in the holotype dentary (IITR/SB/VLM-804) of Indolestes kalamensis gen. et sp. nov. L: total length; TrLn: trigonid length; TrWd: trigonid width; TaLn: talonid length; TaWd: talonid width; TrHt: trigonid height; TaHt: talonid height.

Mesures en millimètres des molaires du dentaire holotype (IITR/SB/VLM-804) de Indolestes kalamensis gen. et sp. nov. L : longueur totale ; TrLn : longueur du trigonide ; TrWd : largeur du trigonide ; TaLn : longueur du talonide ; TaWd : largeur du talonide ; TrHt : hauteur du trigonide ; TaHt : hauteur du talonide.

Table 3 L TrLn TrWd TaLn TaWd TrHt TaHt IITR/SB/VLM-804 (holotype) m2 2.13 1.04 1.44 1.09 1.18 2.02 0.98 m3 2.00 0.95 1.34 1.05 0.99 1.76 0.96

Measurements of lower dentition (p4–m3) of known adapisoriculids including Indolestes kalamensis gen. et sp. nov. (IITR/SB/VLM-804). Data compiled from De Bast et al., 2012, De Bast et al., 2013, Gheerbrant, 1988, Gheerbrant, 1991, Gheerbrant, 1993, Gheerbrant, 1995, Gheerbrant and Russell, 1989, Gheerbrant and Russell, 1991, Prasad and Sahni, 1988, Prasad et al., 1994 and Prasad et al., 2010.

Mesures de la dentition inférieure (p4–m3) d’adapisoriculidés connus incluant Indolestes kalamensis gen. et sp. nov.(IITR/SB/VLM-804). Données compilées à partir de De Bast et al., 2012 and De Bast et al., 2013 ; Gheerbrant, 1988, Gheerbrant, 1991, Gheerbrant, 1993 and Gheerbrant, 1995 ; Gheerbrant and Russell, 1989 and Gheerbrant and Russell, 1991 ; Prasad et Sahni, 1988 ; Prasad et al., 1994 and Prasad et al., 2010.

Table 4 Taxon Specimen Dentition Length (mm) Maximum width (mm) Indolestes kalamensis gen. et sp. nov. IITR/SB/VLM-804 p4 1.97 0.95 Indolestes kalamensis gen. et sp. nov. IITR/SB/VLM-804 m2 2.13 1.44 Indolestes kalamensis gen. et sp. nov. IITR/SB/VLM-804 m3 2.00 1.34 Deccanolestes narmadensis VPL/JU/IM/8 m1 or m2 1.25 0.65 Deccanolestes narmadensis VPL/JU/IM/7 m1 or m2 1.32 0.67 Deccanolestes narmadensis VPL/JU/IM/6 m3 1.23 0.60 Deccanolestes hislopi VPL/JU/NKIM/16 m1 0.95 0.58 Deccanolestes hislopi DUGF/IM/1 p4 1.18 0.55 Deccanolestes hislopi DUGF/IM/1 m1 1.33 0.85 Deccanolestes hislopi DUGF/IM/1 m2 1.18 0.81 Deccanolestes cf. hislopi ITV/R/Mm-7 m1 or m2 0.91 0.60 Deccanolestes cf. hislopi ITV/R/Mm-10 m1 or m2 1.07 0.72 Deccanolestes cf. hislopi ITV/R/Mm-11 m3 1.15 0.70 Deccanolestes cf. hislopi ITV/R/Mm-12 m3 1.13 0.68 Deccanolestes robustus VPL/JU/NKIM/14 m1 1.48 0.94 Afrodon gheerbranti Q2-32/M1986 p4 2.12 1.08 Afrodon gheerbranti N2-12 m1 2.24 1.20 Afrodon gheerbranti O1-03 m1 2.16 1.02 Afrodon gheerbranti N2-13/M1987 m1 2.14 1.12 Afrodon gheerbranti Q1-06/M1988 m2 1.90 1.14 Afrodon gheerbranti Q2-31 m2 1.88 1.20 Afrodon gheerbranti Y1-06 m2 1.98 1.12 Afrodon gheerbranti N2-06/M1989 m3 2.16 1.04 Afrodon chleuhi THR 316 p4 1.25 0.87 Afrodon chleuhi THR 051 m3 1.43 0.93 Bustylus germanicus Wa/537 m1 1.35 0.72 Bustylus germanicus WB 9 m1 1.40 0.83 Bustylus germanicus CR-32-PN m3 1.48 0.96 Bustylus marandati N2-22/M1991 p4 1.18 0.56 Bustylus marandati Q2-05/M1992 m1 1.20 0.64 Bustylus marandati R1-27/M1993 m2 1.22 0.80 Bustylus marandati R1-34 m2 1.24 0.84 Bustylus marandati MZ1-01 m2 1.22 0.96 Bustylus marandati Q2-42/M1994 m3 1.24 0.68 Bustylus folieae N2-06b/M1998 p4 1.34 0.62 Bustylus folieae R1-31/M2000 p4 1.26 0.60 Bustylus folieae O1-08 p4 1.26 0.64 Bustylus folieae N2-06b/M1998 m1 1.50 0.90 Bustylus folieae P2-04/M2002 m1 1.50 0.86 Bustylus folieae N2-07 m1 1.50 0.90 Bustylus folieae O2-01 m1 1.44 0.80 Bustylus folieae N2-06b/M1998 m2 1.38 0.94 Bustylus folieae N1-01/M2003 m2 1.44 0.94 Bustylus folieae R1-10/M2004 m3 1.48 0.80 Bustylus folieae Q2-42 m3 1.24 0.68 Bustylus folieae Q2-09 m3 1.36 0.78 Proremiculus lagnauxi R1-38/M2007 m1 2.18 1.20 Proremiculus lagnauxi R1-74/M2008 m1 or m2 2.04 1.30 Remiculus deutschi CR 1170 m1 or m2 2.66 1.66

Character scores for Indolestes kalamensis gen. et sp. nov. For character definitions see Appendix 1 (De Bast et al., 2013). Note that “?” denotes missing or unknown characters.

Scores des caractères pour Indolestes kalamensis gen. et sp. nov. Pour la définition des caractères, voir l’appendice 1 (De Bast et al., 2013). À noter que « ? » indique des caractères manquants ou inconnus.

Table 5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Indolestes kalamensis gen. et sp. nov. ? ? ? ? ? ? ? ? 1 1 0 ? 1 0 ? 1