Cambay Amber Research Articles

A new species of Sycorax (Sycoracinae: Psychodidae) from the Lower Eocene amber of Tadkeshwar, Gujarat, India

A new species Sycorax longistyla has been recovered in amber from the Tadkeshwar Lignite Mine, Cambay Basin, Gujarat. It belongs to the Sycoracinae, a subfamily of tiny flies, some of which prey on amphibian blood, well-preserved in the Early Eocene Cambay amber. Females of most species have functional mandibles. The new species is distinguished from the extant and extinct representatives by possessing an elongate tubular gonocoxite with a large internal lobe, the gonostylus is curved and longer than the gonocoxite and bears a strong apical spine 0.6 times the length of the gonostylus. The species occurred in sludge-based peat bog spring habitats that existed in the Early Eocene tropical angiosperm Cambay forest.

Another Laurasian connection in the Early Eocene of India: Myrmecarchaea spiders (Araneae, Archaeidae).

The first fossil Archaeidae in Cambay amber from India, of Eocene age, is documented. The inclusion is a spider exuvium and is placed as Myrmecarchaea based on the presence of elongated legs, a slightly elongated pedicel with lateral spurs, and a diastema between coxae III and IV that is similar to M.antecessor from Oise amber. The previous occurrences of the genus are from Baltic and Oise amber, both of Eocene age. Because most spiders, including Archaeidae, only molt as juveniles, the exuvium does not have adult features nor have distinct species-specific features, and a new taxon is not erected. This new record further extends the distribution of the family and genus to India 50–52 million years ago. Myrmecarchaea in Indian Cambay amber provides additional evidence that India in the Early Eocene had affinities with the Palearctic mainland rather than showing Gondwanan insularity.

A new biting midge of the genus Forcipomyia Meigen, 1818 from Miocene Ethiopian amber (Diptera: Ceratopogonidae)

Biting midges (Ceratopogonidae) are a relatively well-studied family of nematocerous flies distributed worldwide, including 6,206 extant and 296 fossil species. To date, 1,146 extant and 32 fossil species in the genus Forcipomyia have been recorded in the world (Borkent & Dominiak, 2020). Biting midges of the subgenus Forcipomyia s. str. are indicative of forests because their larvae and pupae usually live under the bark of rotting trees (Szadziewski, 2018). The oldest records of the genus are from the Eocene. Forcipomyia are reported from early Eocene Fushun amber (one species; Hong, 1981; Stebner et al., 2016; Szadziewski, 2018; Krzemiński et al., 2019), early Eocene Cambay amber (unnamed, Stebner et al., 2017), middle Eocene Sakhalin amber (one species, Szadziewski & Sontag, 2013), Eocene Baltic amber from the Gulf of Gdańsk, Rovno and Bitterfeld (21 species; Szadziewski, 1988, Szadziewski, 1993, Sontag & Szadziewski, 2011), Miocene Dominican amber (10 species, Szadziewski & Grogan, 1998) and Miocene Mexican amber (unnamed, Szadziewski & Grogan, 1996).

Flowers of Apocynaceae in amber from the early Eocene of India.

Early Eocene ambers of the Cambay lignite in Gujarat, India, are well known for their diverse insect fauna and dispersed pollen, but the included flowers have received limited attention. The fossil record of Apocynaceae is relatively poor, and the distinctive floral characters of this family have not been recognized in the fossil record before. Remains of tiny flowers in amber were studied by micro-CT scanning, reflected light, and epifluorescence microscopy. Flowers of Maryendressantha succinifera gen. et. sp. n. have actinomorphic, pentamerous, tubular corollas 2.2-2.3 mm wide, and 1.7-2.1 mm deep with sinistrorse aestivation and androecia consisting of a whorl of five stamens attached by short filaments to the lower half of the corolla tube. Anthers are ovate, rounded basally and apically tapered with their connectives convergent with one another in a conical configuration. The pollen is globose, psilate, tricolporate, and very small (10-11 µm). The combined characters indicate a position within the grade known as subfamily Rauvolfioideae. These fossils, as the oldest remains of Rauvolfioids, complement the fossil records of Apocynoid and Asclepioid fossil seeds from other regions, demonstrating that the Apocynaceae were well established by the early Eocene, mostly consistent with prior divergence estimates for the phylogeny of this family. Potential pollinators, also preserved in the Cambay amber, include mosquitos, gnats, small moths, and stingless bees.

Minute and diverse in fossil sticky stuff: Tanytarsini (Diptera: Chironomidae) from early Eocene Indian Cambay amber

Abstract We here present a pioneering systematic review of fossil dipterans of the tribe Tanytarsini (family Chironomidae) discovered in Indian amber from Cambay. The specimens examined belong to five species: Gujaratomyia miripes,Stempellina stebneri sp. nov., Stempellinella pollex sp. nov., Tanytarsus forfex sp. nov. andTanytarsus ramus sp. nov., which are described. All species belong to the oldest known Tanytarsini and come from the Cambay shale formation in Tadkeshwar, dated to the early Eocene (~54 Mya). Displaying unusual characters/structures of diagnostic and phylogenetic importance, the specimens studied are discussed against the background of the evolution and systematics of the oldest fossil (Eocene) and extant representatives in the tribe. An updated checklist and key to the identification of genera and species of Tanytarsini from Eocene amber is also provided. The spectral characteristics and physical properties of Cambay amber are similar to those of glessite resins, which are discussed in detail in order to substantiate the identity of the amber and the origin of the inclusions studied.

Small and common: the oldest tropical Chrysomelidae (Insecta: Coleoptera) from the lower Eocene Cambay amber of India

Nadein, K.S. & Perkovsky, E.E. 2 July 2019. Small and common: the oldest tropical Chrysomelidae (Insecta: Coleoptera) from the lower Eocene Cambay amber of India. Alcheringa XXX, X–X. ISSN 0311-5518.Three new genera and species of flea beetles (Chrysomelidae: Alticini) are described from the lowermost Eocene Cambay amber: Cambaltica paleoindica Nadein, gen. et sp. nov., Protorthaltica setosella Nadein, gen. et sp. nov., and Davidaltica cambayensis Nadein, gen. et sp. nov. These taxa share a zoogeographic affinity with extant Oriental and Afrotropical flea beetle faunas, with similarities to Afrotropical elements interpreted to be a result of Neogene migrations from Laurasia to Africa. The flea beetles within the Cambay amber are characterized by their small body size (1.2–1.9 mm), and the absence or rarity of larger flea beetles in the Cambay amber forest is assumed to be evidence for a progressive increase in the average body size of tropical flea beetles beginning in the early Eocene.Konstantin S. Nadein [k.nadein@gmail.com], University of Kiel, Zoological Institute, Functional Morphology and Biomechanics, Am Botanischen Garten 1–9, Kiel, Germany; Evgeny E. Perkovsky [perkovsk@gmail.com], Schmalhausen Institute of Zoology, National Academy of Science of Ukraine, Bogdana Khmelnitskogo Str. 15, Kiev, Ukraine, Borissiak Paleontological Institute of the Russian Academy of Sciences, Profsoyuznaya Str. 123, Moscow, 117997, Russia.

Comparison of Biting Midges of the Early Eocene Cambay Amber (India) and Late Eocene European Ambers Supports the Independent Origin of European Ambers

Abstract Of the three genera of Ceratopogoninae dominant in Late Eocene ambers of Europe, the two known are absent in the Early Eocene Cambay amber (India): the Holarctic genus Ceratopogon and the worldwide distributed genus Culicoides, known since the Late Cretaceous. Tropical biting midge genera (Meunierohelea and Leptoconops and genera with feminized male antennae: Camptopterohelea, Eohelea, and Gedanohelea) are abundantly represented in Cambay amber. The proportion of Ceratopogonini with feminized male antennae among all Ceratopogonidae dramatically increases from north to south: from 1.4-2.4 % in unbiased collections of Bitterfeld amber (Humboldt Museum collection) and Baltic amber (the Giecewicz collection) to 7 % in Danish amber and 12.7 % in Rovno amber; their proportion in Cambay amber is 17 %. The proportion of tropical specimens among specimens Ceratopogoninae in unbiased collections is 6.4 % in Baltic amber, 5.3 % in Bitterfeld amber, 21 % in Rovno and Danish amber, and 58 % in Cambay amber. Strong differences in the proportion of tropical components among Ceratopogoninae from different European ambers are in agreement with data on Cambay amber and so are indicative of origin of the European ambers under different climatic and hence geographic environments.

Lygistorrhinidae (Diptera: Bibionomorpha: Sciaroidea) in early Eocene Cambay amber.

One new genus and three new species of Lygistorrhinidae in early Eocene Cambay amber from India are described, which significantly increases our knowledge about this group in the Eocene. Lygistorrhina indica n. sp. is the oldest fossil known from this extant genus. Indorrhina sahnii n. gen. et sp. shows morphological similarities to each of the two extant genera Lygistorrhina and Asiorrhina. Palaeognoriste orientale is the third species known from a group that has only been recorded from Eocene Baltic amber before. The latter finding reveals faunal links between Cambay amber and the probably slightly younger Baltic amber, adding further evidence that faunal exchange between Europe/Asia and India took place before the formation of Cambay amber.

The phylogeny of fossil whip spiders

BackgroundArachnids are a highly successful group of land-dwelling arthropods. They are major contributors to modern terrestrial ecosystems, and have a deep evolutionary history. Whip spiders (Arachnida, Amblypygi), are one of the smaller arachnid orders with ca. 190 living species. Here we restudy one of the oldest fossil representatives of the group, Graeophonus anglicus Pocock, 1911 from the Late Carboniferous (Duckmantian, ca. 315 Ma) British Middle Coal Measures of the West Midlands, UK. Using X-ray microtomography, our principal aim was to resolve details of the limbs and mouthparts which would allow us to test whether this fossil belongs in the extant, relict family Paracharontidae; represented today by a single, blind species Paracharon caecus Hansen, 1921.ResultsTomography reveals several novel and significant character states for G. anglicus; most notably in the chelicerae, pedipalps and walking legs. These allowed it to be scored into a phylogenetic analysis together with the recently described Paracharonopsis cambayensis Engel & Grimaldi, 2014 from the Eocene (ca. 52 Ma) Cambay amber, and Kronocharon prendinii Engel & Grimaldi, 2014 from Cretaceous (ca. 99 Ma) Burmese amber. We recovered relationships of the form ((Graeophonus (Paracharonopsis + Paracharon)) + (Charinus (Stygophrynus (Kronocharon (Charon (Musicodamon + Paraphrynus)))))). This tree largely reflects Peter Weygoldt’s 1996 classification with its basic split into Paleoamblypygi and Euamblypygi lineages; we were able to score several of his characters for the first time in fossils. Our analysis draws into question the monophyly of the family Charontidae.ConclusionsOur data suggest that Graeophonus is a crown group amblypygid, and falls within a monophyletic Paleoamblypgi clade, but outside the family Paracharontidae (= Paracharonopsis + Paracharon). Our results also suggest a new placement for the Burmese amber genus Kronocharon, a node further down from its original position. Overall, we offer a broad phylogenetic framework for both the fossil and Recent whip spiders against which future discoveries can be tested.

The Chironomidae diversity based on records from early Eocene Cambay amber, India, with implications on habitats of fossil Diptera

A fossil fauna of Chironomidae in early Eocene Cambay amber from India is reported for the first time. The fossil assemblage consists of 192 specimens from five subfamilies. Chironomidae from Cambay amber represent a fauna whose composition in the fossil record is most similar to Dominican amber, with the exception of the presence of Podonominae in Cambay amber. Chironomidae genera recorded from Cambay amber indicate the presence of freshwater habitats and standing water bodies as well as springs. Incorporation of other dipteran groups from Cambay amber adds evidence of diverse aquatic and semi-aquatic habitats in the Cambay amber forest and implies entrapment of the fossils from a wide range of different locally separated areas.

Biting Midges (Diptera: Ceratopogonidae) from Cambay Amber Indicate that the Eocene Fauna of the Indian Subcontinent Was Not Isolated.

India’s unique and highly diverse biota combined with its unique geodynamical history has generated significant interest in the patterns and processes that have shaped the current distribution of India’s flora and fauna and their biogeographical relationships. Fifty four million year old Cambay amber from northwestern India provides the opportunity to address questions relating to endemism and biogeographic history by studying fossil insects. Within the present study seven extant and three fossil genera of biting midges are recorded from Cambay amber and five new species are described: Eohelea indica Stebner & Szadziewski n. sp., Gedanohelea gerdesorum Stebner & Szadziewski n. sp., Meunierohelea cambayana Stebner & Szadziewski n. sp., Meunierohelea borkenti Stebner & Szadziewski n. sp., and Meunierohelea orientalis Stebner & Szadziewski n. sp. Fossils of species in the genera Leptoconops Skuse, 1889, Forcipomyia Meigen, 1818, Brachypogon Kieffer, 1899, Stilobezzia Kieffer, 1911, Serromyia Meigen, 1818, and Mantohelea Szadziewski, 1988 are recorded without formal description. Furthermore, one fossil belonging to the genus Camptopterohelea Wirth & Hubert, 1960 is included in the present study. Our study reveals faunal links among Ceratopogonidae from Cambay amber and contemporaneous amber from Fushun, China, Eocene Baltic amber from Europe, as well as the modern Australasian and the Oriental regions. These findings imply that faunal exchange between Europe, Asia and India took place before the formation of Cambay amber in the early Eocene.

A peculiar leg structure in the first non-biting midge described from Cambay amber, India (Diptera: Chironomidae)

ABSTRACTWe present the first specific record of a chironomid of the tribe Tanytarsini from early Eocene Cambay amber, India (52–53 Ma). The oldest known extinct tanytarsine genus, Gujaratomyia Giłka & Zakrzewska, gen. nov., is described on the basis of adult males of G. miripes Giłka & Zakrzewska, sp. nov. The species displays an unusual leg structure with unique leg ratios and tibial armature. The combination of the head and genital apparatus characters supports the hypothesis that Gujaratomyia and Cladotanytarsus are members of a common group within the subtribe Tanytarsina.

The first representative of Tipulomorpha (Diptera) from Early Eocene Cambay amber (India)

ABSTRACTThe first representative of Tipulomorpha in Early Eocene Cambay amber from India is described. The new find belongs to the genus Dicranomyia in the family Limoniidae. This genus has a worldwide distribution today and is relatively common in Eocene Baltic amber. A new species belonging to the subgenus Dicranomyia is described as Dicranomyia (Dicranomyia) indica sp. nov.

Crown Group Lejeuneaceae and Pleurocarpous Mosses in Early Eocene (Ypresian) Indian Amber.

Cambay amber originates from the warmest period of the Eocene, which is also well known for the appearance of early angiosperm-dominated megathermal forests. The humid climate of these forests may have triggered the evolution of epiphytic lineages of bryophytes; however, early Eocene fossils of bryophytes are rare. Here, we present evidence for lejeuneoid liverworts and pleurocarpous mosses in Cambay amber. The preserved morphology of the moss fossil is inconclusive for a detailed taxonomic treatment. The liverwort fossil is, however, distinctive; its zig-zagged stems, suberect complicate-bilobed leaves, large leaf lobules, and small, deeply bifid underleaves suggest a member of Lejeuneaceae subtribe Lejeuneinae (Harpalejeunea, Lejeunea, Microlejeunea). We tested alternative classification possibilities by conducting divergence time estimates based on DNA sequence variation of Lejeuneinae using the age of the fossil for corresponding age constraints. Consideration of the fossil as a stem group member of Microlejeunea or Lejeunea resulted in an Eocene to Late Cretaceous age of the Lejeuneinae crown group. This reconstruction is in good accordance with published divergence time estimates generated without the newly presented fossil evidence. Balancing available evidence, we describe the liverwort fossil as the extinct species Microlejeunea nyiahae, representing the oldest crown group fossil of Lejeuneaceae.

Specialized Myrmecophily at the Ecological Dawn of Modern Ants

Myrmecophiles--species that depend on ant societies--include some of the most morphologically and behaviorally specialized animals known. Remarkable adaptive characters enable these creatures to bypass fortress-like security, integrate into colony life, and exploit abundant resources and protection inside ant nests. Such innovations must result from intimate coevolution with hosts, but a scarcity of definitive fossil myrmecophiles obscures when and how this lifestyle arose. Here, we report the earliest known morphologically specialized and apparently obligate myrmecophile, in Early Eocene (∼ 52 million years old) Cambay amber from India. Protoclaviger trichodens gen. et sp. nov. is a stem-group member of Clavigeritae, a speciose supertribe of pselaphine rove beetles (Coleoptera: Staphylinidae) heavily modified for myrmecophily via reduced mouthparts for trophallaxis with worker ants, brush-like trichomes that exude appeasement compounds, and fusions of many body and antennal segments. Protoclaviger captures a transitional stage in the evolutionary development of this novel body plan, most evident in its still-distinct abdominal tergites. The Cambay paleobiota marks one of the first occurrences in the fossil record of a significant presence of modern ants. Protoclaviger reveals that sophisticated social parasites were nest intruders throughout, and probably before, the ascent of ants to ecological dominance, with ancient groups such as Clavigeritae primed to radiate as their hosts became increasingly ubiquitous.

Whipspiders (Arachnida: Amblypygi) in amber from the Early Eocene and mid-Cretaceous, including maternal care

Two new genera and species of fossil whipspiders (Chelicerata: Arachnida: Amblypygi) are described from Tertiary and Cretaceous ambers of southern Asia. Paracharonopsis cambayensis Engel & Grimaldi, new genus and species, preserved in Cambay amber of Ypresian age from western India is the first Tertiary and Asian fossil of the Paleoamblypygi, a highly relict taxon that includes the Late Carboniferous genus Graeophonus Scudder and the living West African species Paracharon caecus Hansen. Paracharonopsis cambayensis is one of the few examples in Cambay amber of a biotic connection to Africa; most taxa show widespread or Laurasian distributions. Kronocharon prendinii Engel & Grimaldi, new genus and species, is the first Cretaceous amber whipspider and putatively a sister group to the Phrynoidea (= Apulvillata). The holotype female of K. prendinii is preserved with the remains of three nymphs near her, documenting the Early Cretaceous presence of the extended maternal care so distinctive for the order, and a behavioral repertoire widespread among arachnids.

The bees of Early Eocene Cambay amber (Hymenoptera: Apidae)

The fauna of bees known from Early Eocene (Ypresian) Cambay amber are reviewed. Presently only three species have been recovered, all from among the corbiculate Apinae and representing the extinct tribes Electrapini and Melikertini, and all from genera known from the slightly younger middle Eocene Baltic amber. A single, poorly-preserved and fragmentary female of an unidentifiable species of Protobombus Cockerell is recorded. Two new species of the genus Melikertes Engel are documented, one representing a new subgenus, Paramelikertes Engel & Ortega-Blanco, as is a third, fragmentary melikertine of uncertain identity. The new species are Melikertes (Paramelikertes) gujaratensis Engel & Ortega-Blanco, new species, and M. (Melikertes) kamboja Engel & Ortega-Blanco, new species.

The Oldest Fossil of the Subfamily Osoriinae (Coleoptera: Staphylinidae), from Eocene Cambay Amber (India)

ABSTRACT A new rove beetle is described and figured from Early Eocene amber of India. The specimen, though damaged by compression and with a limited number of views for its study, is complete and belongs to the subfamily Osoriinae. Paleosorius cambayensis Ortega-Blanco, Chatzimanolis, and Engel, new genus and new species, is described as the oldest Osoriinae, and its relationship with other fossils in the subfamily is briefly discussed.

Bugs in the Biogeography: Leptosaldinae (Heteroptera: Leptopodidae) in Amber from the Miocene of Hispaniola and Eocene of India

The Leptosaldinae (Leptopodomorpha: Leptopodidae) are considered an isolated subfamily, possibly the sister group to the remaining species of the bug family Leptopodidae. Until now the subfamily consisted of two species: Leptosalda chiapensis Cobben, in Miocene amber from Chiapas, Mexico; and Saldolepta kistnerorum Schuh and Polhemus, a Recent species from Ecuador and Colombia. The new species, Leptosalda dominicana Grimaldi and Engel and L. niarchos Grimaldi and Engel are described from Miocene amber of the Dominican Republic (a third species is recorded but undescribed since it is based on a very fragmentary specimen). Archaesalepta Grimaldi and Engel, new genus, is described for A. schuhi Grimaldi and Engel, new species, preserved in Early Eocene Cambay amber from western India, and which appears to be a sister group to the New World leptosaldines. Unexpected discovery of a leptosaldine from the Old World greatly expands the known distribution and emphasizes the perils of biogeographic scenarios in the absence of fossil data. Archaesalepta schuhi reveals that leptosaldines were once more widespread and that their present-day distribution is relict.

Coniopterygidae (Neuroptera: Aleuropteryginae) in Amber from the Eocene of India and the Miocene of Hispaniola

ABSTRACT The genus Spiloconis Enderlein is comprised of six Recent Asian and Pacific species, ranging from Sri Lanka (and possibly Madagascar) in the west to eastern Australia and Fiji in the east. Two species previously described in Miocene amber from the Dominican Republic, Spiloconis glaesaria Meinander and S. oediloma Engel and Grimaldi, are redescribed for some details. Spiloconis eominuta Grimaldi and Engel, new species, is described in earliest Eocene Cambay amber from Gujarat, India, which has well-preserved male terminalia. Neoconis paleocaribis Grimaldi and Engel, new species, is described from Dominican amber; this Recent genus is known from the southern United States and neotropics. The fossil Spiloconis may have significant biogeographic implications, but definitive determination of this requires a phylogenetic analysis of the 16 Recent genera in the monophyletic subfamily Aleuropteryginae. A Dominican amber—Australasian distribution pattern is known for 18 genera of insects in myriad orders ...