scholarly journals Response of the Oligo-Miocene Bivalve Fauna of the Kutch Basin (Western India) to Regional Tectonic Events

2021 ◽  
Author(s):  
Saurav Dutta ◽  
Devapriya Chattopadhyay
Keyword(s):  
Body Size ◽  
Indian Subcontinent ◽  
Abundant Species ◽  
Negative Influence ◽  
Western India ◽  
Marine Bivalve ◽  
Regional Environment ◽  
Marine Fauna ◽  
Tectonic Events ◽  
Kutch Basin

ABSTRACTTectonic changes has influenced the evolution of the marine community by changing the land and seaway configuration through time. Two such tectonic events during Oligo-Miocene times — the closure of the Tethyan seaway due to development of the Gomphotherium-Landbridge leading to separation of the Arabian Sea from proto-Mediterranean Sea (∼19 Ma) and significant uplift of the Tibetan plateu marking the initiation of the monsoon (∼16 Ma) — represent a classic case of tectonic shift influencing the regional environment of the Indian subcontinent. We investigated the taxonomic and body size related response of the shallow marine fauna to this regional change using bivalves from 11 time-constrained shellbeds of the Kutch Basin (western India) from three formations — Maniyara Fort (Chattian), Khari Nadi (Aquitanian) and Chhasra (Burdigalian-Langian) representing a time span of ∼9 Ma (24.4 – 15 Ma).Our collection of over 2000 individuals represents a total of 15 families and 61 morphospecies. The fossils are predominantly calcitic in nature and families of aragonitic composition are often preserved as molds indicating a potential negative effect of diagenesis. The taphonomic nature, however, does not vary substantially across shellbeds and hence, less likely produced a temporal pattern. The five most abundant species, Ostrea latimarginata, Ostrea angulata, Talochlamys articulata, Anomia primaeva and Placuna lamellata occur in all the formations. The species composition of the Maniyara Fort formation is substantially different from those of the younger formations implying the possible effect of biogeographic separation. Moreover, the absence of proto-Mediterranean taxa in Oligocene shellbeds support a limited faunal exchange as early as ∼24.4Ma (Chattian) ago. We observed a monotonic increase in the overall rarefied species richness and a decrease in evenness from the Maniyara Fort to the Chhasra Formation. However, shellbed analyses show a dominantly conservative behavior of diversity and body size without a strong directional trend through time. Although it is difficult to rule out the negative influence of taphonomy on the diversity of the studied fauna, Oligo-Miocene marine bivalve fauna of the Kutch Basin demonstrate little or no influence of the Tethyan closure and Himalayan upliftment.

scholarly journals An updated generic classification of Cenozoic pleurotomariid gastropods, with new records from the Oligocene and early Miocene of India

2021 ◽  
pp. 1-14
Author(s):  
Kanishka Bose ◽  
Shiladri S. Das ◽  
Subhronil Mondal
Keyword(s):  
Mass Extinction ◽  
Classification Scheme ◽  
New Records ◽  
Indian Subcontinent ◽  
Early Miocene ◽  
Western India ◽  
New Classification ◽  
Kutch Basin ◽  
The Family

Abstract Although taxonomically distinct, the Cenozoic pleurotomariids are the bottlenecked remnants of the Mesozoic members of the family in terms of morphology, with only conical forms surviving the end-Cretaceous mass extinction. Here, we propose an updated classification scheme for the Cenozoic representatives of this group, based on data from the entire Cenozoic pleurotomariid fossil record. We consider all conventional as well as several new characters so that this scheme can readily help to distinguish Cenozoic pleurotomariid genera. Following the new classification scheme, a revision of the generic status of Cenozoic species previously assigned to ‘Pleurotomaria’ Defrance, 1826 is presented. Only a few Cenozoic pleurotomariid gastropods have been reported from the Indian subcontinent. Here we report four species from the Oligocene of the Kutch Basin and the early Miocene (Burdigalian) of the Dwarka Basin of Gujarat, western India, of which two are described as new: Perotrochus bermotiensis n. sp., Entemnotrochus kathiawarensis n. sp., Entemnotrochus cf. E. bianconii, and Entemnotrochus? sp. 1. UUID: http://zoobank.org/89b6ff67-2834-477f-862b-67691104aca4

scholarly journals A Wolf in Another Wolf’s Clothing: Post-Genomic Regulation Dictates Venom Profiles of Medically-Important Cryptic Kraits in India

Toxins ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 69 ◽  
Author(s):  
Kartik Sunagar ◽  
Suyog Khochare ◽  
R. R. Senji Laxme ◽  
Saurabh Attarde ◽  
Paulomi Dam ◽  
...  
Keyword(s):  
Negative Impact ◽  
Indian Subcontinent ◽  
Clinical Effectiveness ◽  
Venom Gland ◽  
Western India ◽  
The Common ◽  
Genomic Regulation

The Common Krait (Bungarus caeruleus) shares a distribution range with many other ‘phenotypically-similar’ kraits across the Indian subcontinent. Despite several reports of fatal envenomings by other Bungarus species, commercial Indian antivenoms are only manufactured against B. caeruleus. It is, therefore, imperative to understand the distribution of genetically distinct lineages of kraits, the compositional differences in their venoms, and the consequent impact of venom variation on the (pre)clinical effectiveness of antivenom therapy. To address this knowledge gap, we conducted phylogenetic and comparative venomics investigations of kraits in Southern and Western India. Phylogenetic reconstructions using mitochondrial markers revealed a new species of krait, Romulus’ krait (Bungarus romulusi sp. nov.), in Southern India. Additionally, we found that kraits with 17 mid-body dorsal scale rows in Western India do not represent a subspecies of the Sind Krait (B. sindanus walli) as previously believed, but are genetically very similar to B. sindanus in Pakistan. Furthermore, venom proteomics and comparative transcriptomics revealed completely contrasting venom profiles. While the venom gland transcriptomes of all three species were highly similar, venom proteomes and toxicity profiles differed significantly, suggesting the prominent role of post-genomic regulatory mechanisms in shaping the venoms of these cryptic kraits. In vitro venom recognition and in vivo neutralisation experiments revealed a strong negative impact of venom variability on the preclinical performance of commercial antivenoms. While the venom of B. caeruleus was neutralised as per the manufacturer’s claim, performance against the venoms of B. sindanus and B. romulusi was poor, highlighting the need for regionally-effective antivenoms in India.

Potential distribution of the endemic Short-tailed ground agama Calotes minor (Hardwicke & Gray, 1827) in drylands of the Indian sub-continent

2021 ◽  
pp. 132-141
Author(s):  
Ashish Kumar Jangid
Keyword(s):  
Vegetation Index ◽  
Indian Subcontinent ◽  
Aridity Index ◽  
Species Distribution Modelling ◽  
Spatial Knowledge ◽  
Western India ◽  
Distribution Modelling ◽  
Modelling Framework ◽  
Specific Species ◽  
Precise Distribution

The Short-tailed ground agama or Hardwicke’s bloodsucker Calotes minor (Hardwicke & Gray, 1827) is known to occur in the Indian subcontinent and is largely confined to arid to semiarid environments, such as hard barren desert and abandoned fields. The precise distribution of this species is largely unknown to date, with few locality records spread biogeographically across Eastern Pakistan, Central and Western India. To improve on the existing spatial knowledge on this species and assess the ability to predict species distributions for taxa with few locality records, we studied the distribution of C. minor using a species distribution modelling framework. Our study allowed us to predict the distribution range of C. minor and help define a niche for this habitat-specific species. Highly probable habitats for C. minor were arid and semi-arid dryland habitats, characterised by plains or less rugged terrain with moderately narrow temperature range, lower aridity index, moderate to low vegetation index, and wide precipitation range. Furthermore, we report four additional occurrence records of C. minor from central Rajasthan.

Nephtyidae (Annelida: Polychaeta) from the Sea of Marmara and Black Sea, with descriptions of two new species

Zootaxa ◽  
2021 ◽  
Vol 5060 (2) ◽  
pp. 33-64
Author(s):  
SEVGI KUŞ ◽  
GÜLEY KURT ◽  
MELIH ERTAN ÇINAR
Keyword(s):  
New Species ◽  
Body Size ◽  
Black Sea ◽  
The Body ◽  
The Black Sea ◽  
Sea Of Marmara ◽  
Marine Fauna ◽  
Black Sea Coast ◽  
Two New Species ◽  
Sea Coast

The present paper deals with the diversity of nephtyid polychaetes (Nephtyidae) from the Sea of Marmara and the Black Sea. Three species belonging to two genera (Micronephthys and Nephtys) were found in the Black Sea (coast of Turkey) and six species belonging to three genera (Inermonephtys, Micronephthys and Nephtys) were found in the Sea of Marmara. The material includes two species new to science, Inermonephtys turcica n. sp. and Nephtys sinopensis n. sp., and a species record (Nephtys kersivalensis McIntosh, 1908) new to the Sea of Marmara’s marine fauna. Nephtys sinopensis n. sp. is mainly characterized by having 1–4 geniculate chaetae in the postacicular position of the parapodia; digitiform antennae, palps, and ventral cirri at chaetiger 1 with swollen tips; small and cirriform branchiae present from chaetiger 4 to the end of the body; poorly developed parapodial prechaetal lamellae in median and posterior chaetigers and long ventral cirri along the body. Inermonephtys turcica n. sp. is mainly characterized by having cushion-like palps with digitiform tips; well developed neuropodial postchaetal lamellae; barred chaetae in preacicular position of the anterior and median parapodia; and branchiae first appearing between chaetiger 3 and 13 (depending on body size).  

scholarly journals Size matters: relationships between body size and body mass of common coastal, aquatic invertebrates in the Baltic Sea

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2906 ◽  
Author(s):  
Johan Eklöf ◽  
Åsa Austin ◽  
Ulf Bergström ◽  
Serena Donadi ◽  
Britas D.H.K. Eriksson ◽  
...  
Keyword(s):  
Body Size ◽  
Baltic Sea ◽  
Body Mass ◽  
Dry Mass ◽  
Negative Influence ◽  
Biologically Active ◽  
Relative Mass ◽  
Potential Influence ◽  
The Baltic Sea ◽  
The Baltic

Background Organism biomass is one of the most important variables in ecological studies, making biomass estimations one of the most common laboratory tasks. Biomass of small macroinvertebrates is usually estimated as dry mass or ash-free dry mass (hereafter ‘DM’ vs. ‘AFDM’) per sample; a laborious and time consuming process, that often can be speeded up using easily measured and reliable proxy variables like body size or wet (fresh) mass. Another common way of estimating AFDM (one of the most accurate but also time-consuming estimates of biologically active tissue mass) is the use of AFDM/DM ratios as conversion factors. So far, however, these ratios typically ignore the possibility that the relative mass of biologically active vs. non-active support tissue (e.g., protective exoskeleton or shell)—and therefore, also AFDM/DM ratios—may change with body size, as previously shown for taxa like spiders, vertebrates and trees. Methods We collected aquatic, epibenthic macroinvertebrates (>1 mm) in 32 shallow bays along a 360 km stretch of the Swedish coast along the Baltic Sea; one of the largest brackish water bodies on Earth. We then estimated statistical relationships between the body size (length or height in mm), body dry mass and ash-free dry mass for 14 of the most common taxa; five gastropods, three bivalves, three crustaceans and three insect larvae. Finally, we statistically estimated the potential influence of body size on the AFDM/DM ratio per taxon. Results For most taxa, non-linear regression models describing the power relationship between body size and (i) DM and (ii) AFDM fit the data well (as indicated by low SE and high R2). Moreover, for more than half of the taxa studied (including the vast majority of the shelled molluscs), body size had a negative influence on organism AFDM/DM ratios. Discussion The good fit of the modelled power relationships suggests that the constants reported here can be used to quickly estimate organism dry- and ash-free dry mass based on body size, thereby freeing up considerable work resources. However, the considerable differences in constants between taxa emphasize the need for taxon-specific relationships, and the potential dangers associated with ignoring body size. The negative influence of body size on the AFDM/DM ratio found in a majority of the molluscs could be caused by increasingly thicker shells with organism age, and/or spawning-induced loss of biologically active tissue in adults. Consequently, future studies utilizing AFDM/DM (and presumably also AFDM/wet mass) ratios should carefully assess the potential influence of body size to ensure more reliable estimates of organism body mass.

Strontium stratigraphy of the Oligocene–Early Miocene shellbeds of the Kutch Basin, western India, and its implications

Lethaia ◽  
2020 ◽  
Vol 53 (3) ◽  
pp. 382-395
Author(s):  
Saurav Dutta ◽  
Devapriya Chattopadhyay ◽  
Debarati Chattopadhyay ◽  
Sambuddha Misra ◽  
Alexandra V. Turchyn
Keyword(s):  
Early Miocene ◽  
Western India ◽  
Kutch Basin

Range extension of the Bengal monitor (Varanus bengalensis) for the Trans-Himalayan Region with an altitude record for monitor lizards

Zootaxa ◽  
2020 ◽  
Vol 4732 (2) ◽  
pp. 337-340
Author(s):  
ASHUTOSH SINGH ◽  
BHUPINDER SINGH RANA ◽  
MUKESH THAKUR ◽  
BASUDEV TRIPATHY ◽  
LALIT KUMAR SHARMA ◽  
...  
Keyword(s):  
Body Size ◽  
Indian Subcontinent ◽  
Distinct Pattern ◽  
Wildlife Protection ◽  
Western Asia ◽  
Monitor Lizard ◽  
Different Types ◽  
Freshwater Habitats ◽  
Desert Areas ◽  
Monitor Lizards

The Bengal monitor lizard or Common Indian monitor lizard (Varanus bengalensis Daudin, 1802) is classified as Least Concern under the IUCN and listed under the Schedule-I of the Indian Wildlife Protection Act 1972. Further, the trade of the species is prohibited as the species is listed in Appendix I of CITES. It is widely distributed over Western Asia, the Indian Subcontinent, and Southeast Asia (Koch et al. 2013). It is reported to occupy both terrestrial as well as freshwater habitats from desert areas to floodplains, scrubland to forests, in different types of terrains at elevations below 1500m (Auffenberg 1994; Papenfuss et al. 2010). Body size of individuals varies from 61 to 175 cm from the tip of the snout to the end of the tail (Auffenberg 1994; Losos and Greene, 1998). Adults are generally grey or greenish-grey in color, with a ventral pattern of grey to black crossbars from the chin to the tail. Adult individuals are less contrasting and have a less distinct pattern than younger individuals. The species shows a sexual dimorphism, with males being heavier (around 7.18 to 10 kg) than females which are about 40% smaller in size (Papenfuss et al. 2010). 

The first specimen of Deinotherium indicum (Mammalia, Proboscidea, Deinotheriidae) from the late Miocene of Kutch, India

2020 ◽  
Vol 94 (4) ◽  
pp. 788-795 ◽  
Author(s):  
Ningthoujam Premjit Singh ◽  
Advait M. Jukar ◽  
Rajeev Patnaik ◽  
K. Milankumar Sharma ◽  
Nongmaithem Amardas Singh ◽  
...  
Keyword(s):  
South Asian ◽  
Late Miocene ◽  
Indian Subcontinent ◽  
Morphological Diversity ◽  
Western India ◽  
Large Species ◽  
Small Species ◽  
Old World ◽  
First Occurrence

AbstractDeinotheriidae Bonaparte, 1845 is a family of browsing proboscideans that were widespread in the Old World during the Neogene. From Miocene deposits in the Indian subcontinent, deinotheres are known largely from dental remains. Both large and small species have been described from the region. Previously, only small deinothere species have been identified from Kutch in western India. In the fossiliferous Tapar beds in Kutch, dental remains have been referred to the small species Deinotherium sindiense Lydekker, 1880, but the specimens are too fragmentary to be systematically diagnostic. Here, we describe a large p4 of a deinothere from the Tapar beds and demonstrate that it is morphologically most similar to Deinotherium indicum Falconer, 1845, a large species of deinothere, thereby confirming the identity of deinotheres at Tapar. Deinotherium indicum from Tapar is larger than other deinotheres identified from Kutch and is the first occurrence of the species in the region. This new specimen helps constrain the age of the Tapar beds to the Tortonian and increases the biogeographic range of this species—hitherto only known from two localities on the subcontinent. This specimen also highlights the morphological diversity of South Asian deinothere p4s and allows us to reassess dental apomorphies used to delimit Indian deinothere species. Lastly, we argue that by the late Miocene, small deinotheres in Kutch were replaced by the large Deinotherium indicum.

scholarly journals Some Eocene Cerithioids (Gastropoda, Mollusca) from Kutch, Western India, and Their Bearing on Palaeobiogeography of the Indian Subcontinent

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Kalyan Halder ◽  
Piyali Sinha
Keyword(s):  
New Species ◽  
New Records ◽  
Middle Eocene ◽  
Indian Subcontinent ◽  
Morphological Variability ◽  
Western India ◽  
Diverse Group ◽  
Wide Geographical Distribution ◽  
Cenozoic Era ◽  
Different Parts

The cerithioids are a diverse group of gastropods found globally as fossil and living animals during the Cenozoic Era. Their systematics is riddled with problems stemming from large morphological variability, homoplasy, and wide geographical distribution. Six cerithioid species are described here from the lower Middle Eocene of Kutch, Gujarat, western India. All but two are new species. They are Palmerella kutchensis, Tenagodus? sowerbyi, Potamides archiaci, and Cerithium harudiensis. The rest are new records from Kutch and were known only from Pakistan. A palaeobiogeographical review based on major published records of benthic molluscs from Pakistan reveals strong endemism. The cerithioid faunas from different parts of Pakistan and this report from Kutch also show strong endemism and often quite localized development. It is argued here that unhindered faunal mixing was not possible in this province since these newly evolved basins were restricted in nature in their Lower Cenozoic history.

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