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Featured researches published by Jan Křeček.


Biological Invasions | 2009

Endemic origin and vast anthropogenic dispersal of the West Indian drywood termite

Rudolf H. Scheffrahn; Jan Křeček; Renato Ripa; Paola Luppichini

Cryptotermes brevis is a common pest of structural lumber and sheltered wood in much of the non-Asian tropics. Until now, no endemic locality, as confirmed by regenerating outdoor populations, was known. A termite survey of the northern coastal desert of Chile and the vicinity of Lima, Peru, yielded 61 outdoor populations of C. brevis taken from 23 different native and exotic species of host woods at 19 localities. We review the taxonomic and biogeographic history of C. brevis and suggest climatic and biological factors that favor or limit C. brevis distribution. We also propose a scenario implicating a post-Colombian release of C. brevis by shipboard infestations and the movement of infested wood during the early Spanish Empire to the present time.


Annals of The Entomological Society of America | 2006

Taxonomy, Biogeography, and Notes on Termites (Isoptera: Kalotermitidae, Rhinotermitidae, Termitidae) of the Bahamas and Turks and Caicos Islands

Rudolf H. Scheffrahn; Jan Křeček; James A. Chase; Boudanath Maharajh; John R. Mangold

Abstract Termite surveys of 33 islands of the Bahamas and Turks and Caicos (BATC) archipelago yielded 3,533 colony samples from 593 sites. Twenty-seven species from three families and 12 genera were recorded as follows: Cryptotermes brevis (Walker), Cr. cavifrons Banks, Cr. cymatofrons Scheffrahn and Křeček, Cr. bracketti n. sp., Incisitermes bequaerti (Snyder), I. incisus (Silvestri), I. milleri (Emerson), I. rhyzophorae Hernández, I. schwarzi (Banks), I. snyderi (Light), Neotermes castaneus (Burmeister), Ne. jouteli (Banks), Ne. luykxi Nickle and Collins, Ne. mona Banks, Procryptotermes corniceps (Snyder), and Pr. hesperus Scheffrahn and Křeček (Kalotermitidae); Coptotermes gestroi Wasmann, Heterotermes cardini (Snyder), H. sp., Prorhinotermes simplex Hagen, and Reticulitermes flavipes Koller (Rhinotermitidae); and Anoplotermes bahamensis n. sp., A. inopinatus n. sp., Nasutitermes corniger (Motschulsky), Na. rippertii Rambur, Parvitermes brooksi (Snyder), and Termes hispaniolae Banks (Termitidae). Of these species, three species are known only from the Bahamas, whereas 22 have larger regional indigenous ranges that include Cuba, Florida, or Hispaniola and beyond. Recent exotic immigrations for two of the regional indigenous species cannot be excluded. Three species are nonindigenous pests of known recent immigration. Identification keys based on the soldier (or soldierless worker) and the winged imago are provided along with species distributions by island. Cr. bracketti, known only from San Salvador Island, Bahamas, is described from the soldier and imago. Two soldierless species, Anoplotermes bahamensis n. sp. and Anoplotermes inopinatus n. sp., from the central Bahamas are described from the imago and worker. The imago of Pa. brooksi is described for the first time. Mutually exclusive distributions were recorded for the following groups: Cr. bracketti/Cr. Cymatofrons + Cr. cavifrons, Ne. mona/Ne. jouteli, Pr. corniceps/Pr. hesperus, R. flavipes/H. cardini + H. sp., and Na. corniger/Na. rippertii. All termites found on the Turks and Caicos also occur in parts of the Bahamas except for the likely exotic H. sp., and the exotic Co. gestroi. Present-day distributions of indigenous termite species are related to two primary factors: dry land connections of the BATC during low sea level stands of the late Pleistocene and the proximity of these emergent lands to the faunal sources of Florida, Cuba, and Hispaniola. Flotsam containing mated reproductives or whole colonies are propagules for overwater dispersal by termites.


Hrc-journal of High Resolution Chromatography | 1998

Volatiles from stink bug, Graphosoma lineatum (L.) and from green shield bug, Palomena prasina (L.), (Heteroptera: Pentatomidae).

Karel Stránský; Irena Valterová; Karel Ubik; Jiří Čejka; Jan Křeček

Keywords: Scent glands; defense substances; n-alkanes; furanones; 2-alkenals; 2-alkenyl acetates; 2-decenols


Insectes Sociaux | 2009

Sexual communication in the termite Prorhinotermes simplex (Isoptera, Rhinotermitidae) mediated by a pheromone from female tergal glands

Robert Hanus; A. Luxová; Jan Šobotník; Blanka Kalinová; Pavel Jiroš; Jan Křeček; Thomas Bourguignon; Christian Bordereau

We studied the post-flight behavior and sex attraction in imagoes of the termite Prorhinotermes simplex (Rhinotermitidae, Prorhinotermitinae). Pairing is mediated by the secretion from tergal glands, exposed by females in a calling posture and highly attractive to males. Analysis of extracts of these glands by means of gas chromatography with electroantennographic detection indicated a chromatographic area corresponding to an intense physiological response of males. The retention characteristics of this area proved to be identical with those of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol. Electroantennographic and behavioral assays revealed that units of picograms of the compound represent a stimulus qualitatively and quantitatively equivalent to one female tergal gland. Thus, we hypothesize that (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol is a major component of the female sex pheromone in P. simplex.


Systematic Entomology | 2016

Revisiting Coptotermes (Isoptera: Rhinotermitidae): a global taxonomic road map for species validity and distribution of an economically important subterranean termite genus

Hou-Feng Li; James W. Austin; Christian Bordereau; Thomas Bourguignon; Stephen L. Cameron; Eliana M. Cancello; Reginaldo Constantino; Paul Eggleton; Theodore A. Evans; Brian T. Forschler; J. Kenneth Grace; Claudia Husseneder; Jan Křeček; Chow-Yang Lee; Timothy R. C. Lee; Nathan Lo; Matthew T. Messenger; Aaron J. Mullins; Alain Robert; Yves Roisin; Rudolf H. Scheffrahn; David Sillam-Dussès; Jan Šobotník; Allen L. Szalanski; Yoko Takematsu; Edward L. Vargo; Akinori Yamada; Tsuyoshi Yoshimura; Nan-Yao Su

Coptotermes Wasmann (Isoptera: Rhinotermitidae) is one of the most economically important subterranean termite genera and some species are successful invaders. However, despite its important pest status, the taxonomic validity of many named Coptotermes species remains unclear. In this study, we reviewed all named species within the genus and investigated evidence supporting the validity of each named species. Species were systematically scrutinized according to the region of their original description: Southeast Asia, India, China, Africa, the Neotropics, and Australia. We estimate that of the currently 69 named species described by accepted nomenclatural rules, only 21 taxa have solid evidence for validity, 44 names have uncertain status, and the remaining species names should be synonymized or were made unavailable. Species with high degrees of invasiveness may be known under additional junior synonyms due to independent parochial descriptions. Molecular data for a vast majority of species are scarce and significant effort is needed to complete the taxonomic and phylogenetic revision of the genus. Because of the wide distribution of Coptotermes, we advocate for an integrative taxonomic effort to establish the distribution of each putative species, provide specimens and corresponding molecular data, check original descriptions and type specimens (if available), and provide evidence for a more robust phylogenetic position of each species. This study embodies both consensus and contention of those studying Coptotermes and thus pinpoints the current uncertainty of many species. This project is intended to be a roadmap for identifying those Coptotermes species names that need to be more thoroughly investigated, as an incentive to complete a necessary revision process.


Invertebrate Systematics | 2013

Towards a revision of the Neotropical soldierless termites (Isoptera : Termitidae): redescription of the genus Anoplotermes and description of Longustitermes, gen. nov.*

Thomas Bourguignon; Rudolf H. Scheffrahn; Jan Křeček; Zoltán T. Nagy; Gontran Sonet; Yves Roisin

Soldierless termites are well represented in the Neotropics where they constitute about one-third of the total termite species richness. However, despite their substantial diversity, they have been neglected by most taxonomists because they lack soldiers. Species identification therefore relies upon worker characters, in particular the anatomy of the digestive tract and the enteric valve armature. Here, in order to provide a solid basis for future taxonomic work on this group, we supply detailed descriptions of the type species of the genus Anoplotermes, A. pacificus, and of a few common and widespread species, which we retain in Anoplotermes: A. banksi, A. parvus and A. janus, sp. nov. We transfer Anoplotermes manni to a new genus, Longustitermes, and place six species into synonymy. This redefinition of the genus Anoplotermes is complemented by DNA sequences of four genetic markers to allow species identification by molecular techniques and future phylogenetic studies. This study represents a first step towards a complete revision of the neotropical Anoplotermes-group.


Annales De La Societe Entomologique De France | 2009

Termites (Isoptera: Kalotermitidae, Rhinotermitidae, Termitidae) of Ecuador

Brian W. Bahder; Rudolf H. Scheffrahn; Jan Křeček; Clifford Keil; Susan Whitney-King

Abstract Termites are an abundant and diverse group in the Neotropics with about 500 species representing 83 genera. The paucity of the termite fauna recorded from Ecuador is due, in part, to a lack of deliberate surveys. We revise the termite fauna of Ecuador and raise the number of species from 25 species to 72 based on our recent termite surveys. Of the 72 species, 18 could not be conclusively identified and are likely new species. Given the limited area that has been covered in surveys of the Ecuadorian termite fauna, there are undoubtedly many more species to be recorded for Ecuador, primarily in the eastern lowland areas, cloud forests on both the eastern and western slopes of the Andes, and the Amazonian lowland forests.


Zootaxa | 2015

Compositermes bani sp.n. (Isoptera, Termitidae, Apicotermitinae), a new species of soldierless termite from Bolivia

Tiago F. Carrijo; Rudolf H. Scheffrahn; Jan Křeček

Species of neotropical Apicotermitinae (Termitidae) are soldierless, restricting species identification in this group to workers or seasonally present winged imagos. All neotropical Apicotermitinae were placed in the genus Anoplotermes, until Mathews (1977) described two new genera, Grigiotermes and Ruptitermes. Fontes (1986) described two more genera, Aparatermes and Tetimatermes. Twenty years passed without any taxonomic advances in this group until Scheffrahn et al. 2006 described two new Anoplotermes species from the West Indies and Bourguignon et al. 2010 described Longustitermes manni, (=Anoplotermes manni Snyder), Anoplotermes janus, and placed six other species into synonymy. Finally, Scheffrahn 2013 described a new genus and species, Compositermes vindai, characterized by a ring of sclerotized paddles at the junction of the enteric valve seating (EVS) and paunch (P3).


Zootaxa | 2017

Described from images: The remarkable soldier of Procryptotermes dioscurae Harris (Isoptera: Kalotermitidae) from Socotra Island

Rudolf H. Scheffrahn; Jan Křeček

Procryptotermes Holmgren is a modestly diverse kalotermitid genus endemic to numerous islands and archipelagos of the worlds tropical oceans (Scheffrahn Křeček 2001). Mainland records from southern India (Bose 1979, Roonwal Chhotani 1963, Thakur 1975), Queensland Australia (Watson and Abbey 1993), and the Yucatan Peninsula (Scheffrahn and Křeček 2001), also approximate oceanic coastlines. The soldier of Procryptotermes is distinguished from most other kalotermitids by long, sickle-shaped mandibles and a rather weak or absent frontal flange or protuberance (Krishna 1961). The winged imago of Procryptotermes is similar to that of Cryptotermes Banks in which the median vein is unsclerotized and intersects the radial sector near mid-wing. Of the fourteen described species of Procryptotermes (Scheffrahn Křeček 2001), only one species, P. dioscurae Harris 1954, lacks a description of the soldier caste. It was described from three winged imagos collected from lights on Socotra Island, Yemen. Unlike soldiers, the imago caste is not present in the colony year round and often lacks species-level diagnostic characters. Therefore, the description of the soldier caste is highly desirable for most termite species.


Florida Entomologist | 2016

Proliferation of the invasive termite Coptotermes gestroi (Isoptera: Rhinotermitidae) on Grand Cayman and overall termite diversity on the Cayman Islands

Rudolf H. Scheffrahn; Hartwig H. Hochmair; Francesco Tonini; Jan Křeček; Nan-Yao Su; Peter Fitzgerald; Kieran Hendricken; James A. Chase; John R. Mangold; Jeremy Olynik

Abstract The Asian subterranean termite, Coptotermes gestroi (Wasmann) (Isoptera: Rhinotermitidae), was discovered on Grand Cayman Island in 2000 and, by 2014, had been recorded from 102 land-based localities. These data were used in a hierarchical cluster analysis to identify homogeneous clusters of sites to estimate separate introduction points on the island. Results suggest 4 separate introductions of C. gestroi to Grand Cayman by boat and 1 by land transport from other previously infested parts of the island. The infestations by boat could be either primary introductions (originating from another island) or secondary introductions (originating from other previously infested parts of Grand Cayman). An individual-based model was used to simulate non-anthropogenic spread of C. gestroi over Grand Cayman from 2014 to 2050. The model predicts that by 2050, most of the western part of Grand Cayman will likely be heavily infested by C. gestroi, whereas patches of unsuitable habitat restrict the expansion of the species over the central and eastern parts of the island. In the absence of further human introductions, it will likely take a century for C. gestroi to saturate the island by natural dispersal only. Based on detailed termite diversity surveys, we provide updated records for 14 termite species, collectively, on Grand Cayman, Little Cayman, and Cayman Brac.

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Thomas Bourguignon

Czech University of Life Sciences Prague

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Jan Šobotník

Czech University of Life Sciences Prague

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Yves Roisin

Université libre de Bruxelles

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Blanka Kalinová

Academy of Sciences of the Czech Republic

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Irena Valterová

Academy of Sciences of the Czech Republic

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Robert Hanus

Academy of Sciences of the Czech Republic

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