Cretaceous Research 89 (2018) 174e182 Contents lists available at ScienceDirect Cretaceous Research journal homepage: www.elsevier.com/locate/CretRes Short communication Discovery of a Nitidulidae in Cretaceous Burmese amber (Coleoptera, Cucujoidea) with description of a new genus and taxonomic notes * Alexander G. Kirejtshuk a, b, , Philipp E. Chetverikov c a Zoological Institute, Russian Academy of Sciences, Universitetskaya emb., 1, 199034 St. Petersburg, Russia b CNRS UMR 7205, Museum national d'histoire naturelle, CP 50, Entomologie 45, rue Buffon, F-75005 Paris, France c Department of Invertebrate Zoology, Saint-Petersburg State University, Universitetskaya emb., 7/9, 199034 St. Petersburg, Russia article info abstract Article history: The present paper describes a new genus and species, Sorodites angustipes, that represents the first Received 21 January 2018 nitidulid found in Cretaceous Burmese amber. It is assigned to the Soronia-generic complex (subfamily Received in revised form Nitidulinae, tribe Nitidulini). This specimen differs from all known members of the family by its sub- 14 March 2018 cylindrical to cylindrical tarsomere 3 (not lobed as in most members of the family), the pro- and mes- Accepted in revised form 22 March 2018 otarsi with lobed tarsomeres 1 and 2, and also from all members of the subfamily Nitidulinae by its Available online 22 March 2018 antennal club having a weak dorsoventral compression. The exuvium described as probable Sorodites angustipes represents a first Mesozoic remains of preimaginal instar of the family Nitidulidae. The Sor- Keywords: fi fi Nitidulinae onia- and Phenolia-complexes are re-de ned and clari ed, and attribution of the genus Cacconia Sharp, fi Nitidulini 1890 to the second complex is con rmed. Soronia- and Phenolia-complexes of genera © 2018 Elsevier Ltd. All rights reserved. New genus New species 1. Introduction from the collection of Carsten Grohn€ (Hamburg, who forwards holotypes to the Institute and Museum of Geology and Palae- The sap beetles (Nitidulidae Latreille, 1802) represent a rather ontology at Hamburg University) and from Anders Damgaard diverse group in the Recent fauna but remain poorly known in (Copenhagen, with holotypes deposited in the Zoological Museum fossils (in the fossil record only 31 genera, including 17 extinct ones in Copenhagen). These undescribed species from Burmese amber have been recorded and 52 species have beed described so far: are rather different from the groups of the Recent fauna and can be Kirejtshuk and Ponomarenko, 2018; Kirejtshuk and Nel, 2018). A assigned to new genera in both Nitiduline- and Carpophiline- generic classification was proposed by Kirejtshuk (2008) with later lineages. Their study brings important information on late Meso- systematic additions and corrections (Kirejtshuk, 2009, 2011a, zoic diversification of nitidulids and will provide modifications of 2011b; Kirejtshuk and Kurochkin, 2010; Kurochkin and the current systematics of the family based on new phylogenetic Kirejtshuk, 2010; Kirejtshuk and Kirejtshuk, 2012; Kirejtshuk and reconstructions. The present paper describes a new fossil from Mantic, 2015; Kirejtshuk and Kovalev, 2016, 2017). New data, still Burmese amber dated near the boundary between the early and unpublished, will require additional modifications. The principal late Cretaceous. No member of the Nitidulidae was previously taxonomic combinations and synonymies used in the present paper described from this resource, although this family was mentioned are explained and clarified in the latter publications. The fossil re- earlier from this amber site (Rasnitsyn and Ross, 2000). cord of this family based on the web-catalogue by Kirejtshuk and Ponomarenko (2018) was recently updated by Kirejtshuk and Nel (2018). The first author found numerous nitidulid specimens in 2. Material and methods Burmese amber, and at the moment has at his disposal more than ten new species awaiting description. Most of them were obtained The holotype of Sorodites angustipes gen. et sp. nov. (GPIH 4592, coll. Grohn€ no. 11022) and a syninclusion of larval exuvium are deposited in the Institute of Geology and Palaeontology and Museum (Geologo-Palaontologisches€ Institut u. Museum), Univer- * Corresponding author. Zoological Institute, Russian Academy of Sciences, Uni- versitetskaya emb., 1, 199034 St. Petersburg, Russia. sity of Hamburg. These specimens were examined using a Leica MZ E-mail addresses: [email protected], [email protected] (A.G. Kirejtshuk). 12.0 stereomicroscope with a DFC290 digital camera at the https://doi.org/10.1016/j.cretres.2018.03.021 0195-6671/© 2018 Elsevier Ltd. All rights reserved. A.G. Kirejtshuk, P.E. Chetverikov / Cretaceous Research 89 (2018) 174e182 175 Zoological Institute of the Russian Academy of Sciences (St. with a shallowly excised anterior edge and rather deep sinuations Petersburg) and an Olympus SCX9 stereomicroscope equipped with along posterior edge at each side of the scutellum and the male an Olympus camera at the Museum national d'histoire naturelle protibia with proximal dilatation along its inner edge. Finally, the (Paris). In addition, these specimens were also studied with a Leica new genus has its elytral apices widely rounded, while the TCS SP2 confocal laser scanning microscope (CLSM) in St. Peters- remainding groups of this complex are characterized by the burg State University as described previously (Kirejtshuk et al., conjointly subacuminate elytral apices and at most only with a small 2015) with slightly modified adjustments of the confocal micro- sutural angle. Some important structural characters of the fossil are scope system: excitation wavelength was 405 nm (blue laser, 80% not observable in the holotype, such as peculiarities of the upper intensity), emission wavelength range was of 415e800 nm, acqui- surface of the head and structure of mouthparts, but other charac- sition resolution 1024 Â 1024 pixels, level of gain 350e400, frame ters, which are clearly visible, make it possible to show the distinct average 1 or 2, and zoom range of 1.2e3.0 times. Between 20 and 98 characters that support the erection of a new genus and species. optical slices were recorded from each specimen examined. The Notes 2. The new genus is represented by only one species and, digital images of the confocal stacks were processed using Fiji Open therefore, the diagnosis of both are similar (“descriptio generica Source Image Processing Package to obtain the maximum intensity specifica”). projections (MIP). Three-dimensional representations of the insect Etymology. The name of this new genus is formed from the generic surface topography were carried out using Amira 5.3.2 software. All names Soronia and Lordites; masculine gender. 3-dimensional images were recorded using “PrintScreen” keyboard Diagnosis. Sorodites gen. nov. should be regarded as belonging to function or “Snapshot” command embedded in Amira. Finally, the the Soronia-complex of genera (defined by Kirejtshuk (2003, 2008; specimens were investigated under Nikon TE300 fluorescent mi- etc.): Amphotis Erichson, 1843; Annachramus Kirejtshuk, 1995; croscope with the excitation: 475e490 nm (blue), emission: Hisparonia Kirejtshuk, 2003; Lobiopa Erichson, 1843; Macleayania 506e533 nm (green) and some reconstructions were made using Kirejtshuk, 2003; Microsoronia Kirejtshuk et Kurochkin, 2010; Helicon Focus Pro 4.60 software. For comparisons with other Omosiphila Kirejtshuk, 1990; Ornosia Grouvelle, 1899; Pleoronia members of the family, the authors used fossil and recent species Kirejtshuk, 2003; Sebastianiella Kirejtshuk, 1995; Soronia; Stenor- from the Zoological Institute of the Russian Academy of Sciences onia Kirejtshuk, 2003 Temnoracta Kirejtshuk, 1988). However, (St. Petersburg), and Museum national d'histoire naturelle (Paris). except for the above-mentioned characters of the antennal club, pro- and mesotarsi, pronotal structural peculiarities and male 2.1. Geological setting protibia, the new fossil genus differs from: - Amphotis in the not enlarged (to moderately enlarged) scape, The amber pieces with inclusions originated from mines in the pronotum somewhat narrowing posteriad and with obtuse Hukawng Valley in the state of Kachin in Myanmar. The fossil resin posterior angles, lack of a trace of both longitudinal ribs and has been dated stratigraphically and radiometrically from late longitudinal rows of punctures associated with hairs on the Albian to early Cenomanian in the present century (Cruickshank elytra, short antennal grooves, a submetacoxal line deviating and Ko, 2003; Jarzembowski et al., 2017; etc.). A probably Cen- from the posterior edge of cavity and subcylindrical meta- omanian radiometric age of Burmese amber has been proposed; tarsomeres 1e3; however, the amber tested was from sedimentary beds, indicating - Annachramus in the subflattened dorsum, subunicolorous body that it had been re-deposited (Shi et al., 2012). Thus, the age of this coloration (without a pattern of spots on elytra), weakly amber remains unclear, although its concentration of amber with developed subuniform and recumbent pubescence with lack of inclusions in a certain geological layers gives evidence that its longitudinal rows on elytra, pronotum with widely explanate deposition occurred under peculiar conditions and during definite sides, distinct sutural angle between elytral apices, not enlarged term. Nuclear magnetic resonance spectra and the presence of (to moderately enlarged) scape, lack of interfacetal hairs, sub- araucaroid wood fibres