Genus Crematogaster Research Articles

Crematogaster gadagkari sp. nov. (Hymenoptera: Formicidae), a new species of an acrobat ant from India.

We described a new species Crematogaster gadagkari sp. nov. from India. The species is collected from the North East Himalaya. It resembles C. rogenhoferi Mayr, 1879 and Crematogaster himalayana Forel, 1902, but can be distinguished from both species on the basis of sculpture and propodeal spine length. An identification key to the known species of the genus Crematogaster from India is also updated. In addition, a DNA barcode for the newly described species is also provided with Genbank accession number "OP807010".

Interactions between egg parasitoids and predatory ants for the biocontrol of the invasive brown marmorated stink bug Halyomorpha halys

AbstractThe brown marmorated stink bug Halyomorpha halys is an Asian species that has become a major agricultural pest in North America and Europe. Ants from the genus Crematogaster are predators of H. halys nymphs in Asia, as well as in the Mediterranean, where known native predators are still few. At the same time, ants usually do not harm H. halys eggs, which are the target of the main biological control agents, the scelionid parasitoids of the genus Trissolcus. However, ants, as generalist predators and territorial organisms, may kill or displace a variety of other insects, potentially interfering with parasitoids and biological control programmes. We conducted laboratory experiments to investigate the interactions between the Mediterranean ant Crematogaster scutellaris and the parasitoids T. japonicus and T. mitsukurii, evaluating the possibility that the ants could damage the parasitized eggs, attack the parasitoids during emergence or interfere with the egg‐laying behaviour of female parasitoids. Our results demonstrate that C. scutellaris is not able to damage parasitized eggs and is not aggressive towards adult parasitoids at any stage. The presence of ants can slow down the parasitization rate in T. mitsukurii females in the smallest laboratory setups; however, this has not been observed in a more natural setting. We suggest that ants may play a complementary role together with egg‐parasitoids in the control of H. halys without interfering with each other.

Multilocus phylogeny and historical biogeography of theCrematogaster inflata-group (Hymenoptera: Formicidae) in South-East Asia

AbstractA recent molecular phylogeny of the genus Crematogaster reclassified some members of the former subgenera Paracrema and Physocrema into the C. inflata-group, now comprised of five species: C. ampullaris, C. inflata, C. modiglianii, C. onusta and C. subcircularis. Here, a molecular analysis of the Crematogaster inflata-group and eight other species of the former subgenus Physocrema (C. aurita, C. difformis, C. mucronata, C. physothorax, C. sewardi, C. tanakai, C. vacca and C. yamanei) is conducted using a total of c. 4 kb of sequence data from six nuclear protein-coding genes and two mitochondrial genes. Monophyly of the C. inflata-group is strongly supported. A revised morphological delineation of the subgroups is proposed, supported by the molecular phylogeny: three morphologically distinct subgroups, the C. difformis-subgroup, the C. vacca-subgroup and the C. inflata-subgroup. Molecular dating and biogeographical analyses indicate that the C. inflata-group originated in the Sundaic region around the Middle Miocene 12 Mya and diversified from the Late Miocene to Pliocene. Ancestral state reconstructions indicate that the C. inflata-group diversified from an ancestor with a swollen propodeum and circular-shaped metapleural gland opening. Biogeographical reconstruction indicates that dispersal to peripheral areas and allopatry due to sea-level changes shaped the evolutionary history of the C. inflata-group.

Ecology of Myrmecofauna (Genus: Crematogaster) Associated to Helixanthera mannii (Oliv.) Danser (Loranthaceae) to Cocoa Trees in Oboa: Center Region of Cameroon, Africa

In order to find an effective control method against Helixanthera mannii (Oliv) Danser, parasite of agroecosystems in the northern part of the city of Yaoundé, a study of the myrmecofauna associated with this plant was carried out in an orchard of Oboa in Soa district. The total parasitism rate by Helixanthera mannii Danser was 20.43% for the entire orchard. 168 ants belonging to 12 species including ten genera and four subfamilies were collected from unparasitized and parasitized host individuals of Theobroma cacao. 86 ants belonging to two subfamilies were collected from selected branches of Helixanthera mannii from parasitized cocoa trees, namely Formicinae (Camponotus flavomarginatus) and Myrmicinae (Crematogaster (oxygyne) sp., Crematogaster (decacrema) sp. and Cataulacus sp. ) or 58.14% of the myrmecofauna during the flowering of this Loranthaceae and 41.86% during its fruiting. The ants of the genus Crematogaster proved to be the most active and abundant, i.e., 76.83% on non-parasitized hosts and 93.03% on hosts parasitized by Theobroma cacao by Helixanthera mannii. Crematogaster (oxygyne) sp. had an occupancy rate of 69.77% followed by Crematogaster (decacrema) sp. with 23.26% or 93.03% of the myrmecofauna recorded during the flowering and fruiting of Helixanthera mannii. Crematogaster (oxygyne) sp. proved to be the most active ant on these hosts. Note that the dominant ant status recognized for ants of the genus Crematogaster and their foraging activity on the flowers and fruits of Helixanthera mannii can contribute to the reduction of these parasitisms.

Crematogaster bonnieae (Hymenoptera, Formicidae), a New Acrobat-Ant Species from the Western Ghats, India

A new species of the acrobat-ant genus Crematogaster, C. bonnieae, is described from the Western Ghats, India based on workers. The morphology of the new species is fairly distinguishable from other congeners by the following combination of characters: relatively large eyes; long antennal scapes, surpassing posterior head margin; propodeal spines reduced, tuberculate; 11-segmented antennae, and 3-segmented club. An identification key to the 33 Indian species/subspecies of Crematogaster is also provided.

The ant associates of Lycaenidae butterfly caterpillars – revisited

Based on a global compilation of data on ant associates of 523 Lycaenidae species, a synthesis is attempted as to which ants participate in these interactions. Ants from 63 genera have thus far been observed as visitors of facultative myrmecophiles or as hosts of obligate myrmecophiles among the Lycaenidae. Over 98% of records come from nectarivorous and trophobiotic ants in just three subfamilies, viz. Formicinae, Myrmicinae and Dolichoderinae, with the genera Crematogaster and Camponotus occupying the top ranks. Accumulation analysis suggests that rather few ant genera remain to be added to the list of associates. The representation of ant genera as attendants of lycaenid immatures is related to their global species richness, but with some notable exceptions. Ants that form ecologically dominant, large, long-lived colonies are over-represented as hosts of obligate myrmecophiles. The taxonomic diversity of lycaenid-ant associations is highest in the Oriental and Australian region, and lowest in the Neotropical and Afrotropical region. Among tropical African lycaenids, this is due to two butterfly lineages (genus Lepidochrysops and subfamily Aphnaeinae) that have massively radiated in the Neogene, but mostly maintaining their general affiliations with either Camponotus or Crematogaster ants, respectively. Many tropical and subtropical lycaenids nowadays form associations also with invasive alien tramp ants, giving rise to novel mutualistic interactions.

Association of Strymon serapio (Lycaenidae: Theclinae) and Castnia invaria (Castniidae: Castniini) with the Habitat-Forming Bromeliad Encholirium spectabile (Bromeliaceae: Pitcairnioideae) in the Brazilian Semiarid Caatinga

Bromeliads provide habitat and food resources for various organisms. Besides the nectar and pollen, the leaf and fruit tissues of these plants supply food for various animal groups. Among the groups that feed on bromeliads, herbivores are the ones that cause the most damage to these plants; among such organisms, some are well known, such as butterfly and moth caterpillars. Here we will describe some of the ecological relationships between the butterflies Strymon serapio and moths Castnia invaria in association with the rupicolous habitat-forming bromeliad Encholirium spectabile. In rocky outcrops of the Brazilian Semiarid Caatinga, S. serapio caterpillars were frequently observed in the blooms of E. spectabile and adults in the leaves, as well as adults of C. invaria. However, in C. invaria the larvae develop inside the bromeliads. Adults of both species were associated with E. spectabile throughout the year in the study area. We observed S. serapio eggs and larvae mainly during the beginning of the dry season, and the eggs of C. invaria, occur mainly during the rainy season. Regarding the daily activity period, the two species show diurnal habits. Caterpillars of S. serapio develop mutualistic relations with ants of the genus Crematogaster in the blooms of E. spectabile. This is the first record for this kind of ant-butterfly interactions taking place in Encholirum bromeliads, although they have already been cited for other species of Bromeliaceae. The record of these interactions in E. spectabile suggests that these bromeliads are relevant for local biodiversity, also regarding interactions with species of commercial interest, which use the E. spectabile as a host plant..

Complete mitochondrial genome of the acrobat ant Crematogaster teranishii Santschi, 1930 (Formicidae; Hymenoptera)

The genus Crematogaster is a diverse group of ants found around the world. We have completed the mitochondrial genome of Crematogaster teranishii, which is the first mitochondrial genome of the genus. The mitochondrial genome is 17,442 bp long and 20.3% in GC ratio, which is similar to those of other ants. It contains 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a control region with same gene order to other myrmicine species. The intergenic region between nad3 and trnA was unusually long compared to other ant species. Phylogenetic analysis showed that C. teranishii was closely related to other members of tribe Crematogastrini.

Sympolymnia, a new genus of Neotropical ant-like spider, with description of two new species and indirect evidence for transformational mimicry (Araneae, Salticidae, Simonellini)

Sympolymnia, a new genus of myrmecomorph jumping spider belonging to the tribe Simonellini Peckham, Peckham & Wheeler, 1889, is described. It comprises five species: the type species, Sympolymnia lucasi (Taczanowski, 1871), comb. nov., Sympolymnia lauretta (Peckham & Peckham, 1892), comb. nov., Sympolymnia edwardsi (Cutler, 1985), comb. nov. and Sympolymnia shinahotasp. nov. and S. cutlerisp. nov.Sympolymnia lauretta (Peckham & Peckham, 1892) is recorded from Bolivia for the first time. Ontogenetic shifts of ant-resemblance are observed: Juveniles of S. cutlerisp. nov. and S. lauretta mimic black ants of the genus Crematogaster Lund, 1831, but those of S. shinahotasp. nov. most closely resemble Pseudomyrmex ethicus (Forel, 1911). Adults of S. cutlerisp. nov., S. lauretta and S. shinahotasp. nov. resemble the ant Camponotus sanctaefidei Dalla Torre, 1892 and orange adults of S. shinahotasp. nov. are putative mimics of Camponotus latangulus Roger, 1863.

The ant cricket Myrmecophilus orientalis on the Dodecanese Islands, Greece (Orthoptera: Myrmecophilidae)

This study reports the occurrence of the ant cricket Myrmecophilus orientalis Stalling, 2010 on the Dodecanese Islands Kos and Tilos, Greece. This is the first evidence of M. orientalis from Greece and Europe. The species lives in ant nests under stones and in dead wood in open scrubland and pine forests. The adults were found in the nests of large Camponotus species, while the juveniles were found in the nests of small ant species of the genera Crematogaster and Lepisiota. We assumed that the species changes the host ant species during its life cycle.

A new subterranean Crematogaster with one ommatidium from Cambodia, based on morphology and DNA (Hymenoptera: Formicidae)

Abstract A subterranean myrmicine ant Crematogaster monocula sp. nov. is described based on two worker specimens from Cambodia. This species belongs to the C. biroi group of the subgenus Orthocrema Santschi, 1918, which is characterized by developed subpetiolar process, developed subpostpetiolar process and sculptured mesosoma. The new species is easily distinguished from other species of Crematogaster Lund, 1831 by having only one ommatidium. DNA sequences comprising a 761 bp fragment of the 3’ region of the mitochondrial COI gene were amplified and analyzed for C. monocula sp. nov. and other closely related species from the same group. The interspecific COI divergence is 17.8% for C. monocula sp. nov. and C. reticulata Hosoishi, 2009. This species is unique in having the smallest eye in the genus Crematogaster.

First Record of the Ant Genus Crematogaster (Hymenoptera: Formicidae) from the Late Eocene European Ambers

The ant genus Crematogaster Lund, 1831 is recorded for the first time from the Late Eocene Rovno amber, Ukraine (Priabonian stage, 33.9–37.8 Ma). C. primitivasp. nov. is described based on single male. It well differs from males of the extant species by the 13-segmented antennae (vs. 11–12-segmented in modern species). By this feature it resembles the fossil C. praecursorEmery, 1891 described from the Sicilian amber (Early Oligocene, Rupelian stage, 27.8–34.9 Ma), but differs from that species by its distinctly longer antennal scape and by some details of the forewing venation. Only one other fossil Crematogaster species is known – C. auroraLaPolla et Greenwalt, 2015, which was described based on the imprints of two queens from the Middle Eocene Kishenehn Formation, USA (ca. 46 Ma); however, we consider that the ascription of this species to Crematogaster is somewhat questionable.

Phylogenetic analysis and systematic position of two new species of the ant genus Crematogaster (Hymenoptera, Formicidae) from Southeast Asia

Two distinct new species of the ant genus Crematogaster, C. khmerensis sp. nov. and C. pfeifferi sp. nov., are described from Cambodia and Malaysia, respectively. The two species are unique among Asian Crematogaster in that they have vertically directed propodeal spines, but their systematic positions have not been determined based on morphological characters alone. Molecular phylogenetic analysis of 89 Crematogaster taxon matrices previously published plus C. khmerensis sp. nov., using nuclear genes, reveals that C. khmerensis sp. nov. is nested within the Australo-Asian Crematogaster clade. Morphological assignment of the developed pronotal shoulders implies a close relationship between C. khmerensis sp. nov. and the C. tetracantha-group. Based on molecular and morphological evidence, we erect a new species group, C. khmerensis-group, to contain C. khmerensis sp. nov. and C. pfeifferi sp. nov. Divergence time estimates using MCMCTree shows that the root node of the C. khmerensis sp. nov. terminal is estimated to be of middle Miocene age at 15 million years old. The position of the C. khmerensis-group well supports the Oriental- to Australian-region dispersal history that has been proposed for the Australo-Asian Crematogaster clade.

The evolution of a complex trait: cuticular hydrocarbons in ants evolve independent from phylogenetic constraints

Cuticular hydrocarbons (CHCs) are ubiquitous and highly diverse in insects, serving as communication signal and waterproofing agent. Despite their vital function, the causes, mechanisms and constraints on CHC diversification are still poorly understood. Here, we investigated phylogenetic constraints on the evolution of CHC profiles, using a global data set of the species-rich and chemically diverse ant genus Crematogaster. We decomposed CHC profiles into quantitative (relative abundances, chain length) and qualitative traits (presence/absence of CHC classes). A species-level phylogeny was estimated using newly generated and previously published sequences from five nuclear markers. Moreover, we reconstructed a phylogeny for the chemically diverse Crematogaster levior species group using cytochrome oxidase I. Phylogenetic signal was measured for these traits on genus and clade level and within the chemically diverse C.levior group. For most quantitative CHC traits, phylogenetic signal was low and did not differ from random expectation. This was true on the level of genus, clade and species group, indicating that CHC traits are evolutionary labile. In contrast, the presence or absence of alkenes and alkadienes was highly conserved within the C.levior group. Hence, the presence or absence of biosynthetic pathways may be phylogenetically constrained, especially at lower taxonomic levels. Our study shows that CHC composition can evolve rapidly, allowing insects to quickly adapt their chemical profiles to external selection pressures, whereas the presence of biosynthetic pathways appears more constrained. However, our results stress the importance to consider the taxonomic level when investigating phylogenetic constraints.

Taxonomic Revision of the Obligate Plant-Ants of the Genus Crematogaster Lund (Hymenoptera, Formicidae, Myrmicinae), Associated with Macaranga Thouars (Euphorbiaceae) on Borneo and the Malay Peninsula

The taxonomy and natural history of ants of the genus Crematogaster Lund, 1831 (Crematogaster borneensis-group of the former subgenus Decacrema) obligately associated with myrmecophytic host-plants of the euphorb genus Macaranga are reviewed. Within this group of ants Crematogaster borneensis André, 1896 (with five subspecies and four varieties), Crematogaster captiosa Forel, 1910 as well as Crematogaster decamera Forel, 1910 have previously been described from SE Asia. Here we synonymise C. borneensis subsp. capax Forel, 1911, C. borneensis subsp. hosei Forel, 1911, C. borneensis subsp. sembilana Forel, 1911, and C. borneensis var. macarangae Viehmeyer, 1916 with C. borneensis André, 1896. Crematogaster borneensis var. harpyia Forel, 1911, C. borneensis var. insulsa Forel, 1911, C. borneensis subsp. symbia Forel, 1911, and C. borneensis subsp. novem Forel, 1911 are synonymised with C. captiosa Forel, 1910. In addition we describe five new species: C. claudiae sp. nov., C. hullettii sp. nov., C. linsenmairi sp. nov., C. maryatii sp. nov., and C. roslihashimi sp. nov.. Seven of these eight species are placed into two informal species subgroups based on queen morphology, life-history characters and a formerly published molecular phylogeny. Keys are provided for the identification of queens and workers, as well as natural history information on the eight ant species. The morphology of these Macaranga-associated Crematogaster (formerly Decacrema) species is compared to the only other three species described for this former subgenus in SE Asia, i.e. C. angulosa André, 1896, C. biformis André, 1892 and C. cephalotes Smith, 1857.

Systematics and biogeography of the ant genusCrematogasterLund subgenusOrthocremaSantschi in Asia (Hymenoptera: Formicidae)

The subgenus Orthocrema of the ant genus Crematogaster is a well defined group and diverse in the tropical Asia. Its systematics has remained poorly understood because of a lack of modern revisionary work. Crematogaster (Orthocrema) is revised for the Asian region, and 27 species including ten new species are recognized. Five species groups: the C. baduvi group (4 spp.); the C. binghamii group (3 spp.); the C. biroi group (10 spp.); the C. moatensis group (1 sp.); the C. quadriruga group (9 spp.) are established based on worker caste morphology. A key to Asian species of the subgenus Orthocrema based on the worker caste is given. Phylogenetic relationships of Asian Orthocrema are analyzed. The analysis revealed that the C. baduvi-, C. binghamii-, and C. biroi groups are monophyletic, and that the allopatric distribution patterns of closely related species imply that Asian Orthocrema is composed of relatively young taxa. There have been at least three west-to-east dispersal events across Wallace's line in the C. baduvi-, C. quadriruga- and C. biroi groups.

One-Step Synthesis of Racemic 6-Methyloctan-3-One, an Alarm Pheromone Component of Ants of the Genus Crematogaster

6-Methyloctan-3-one (1) was identified as a component of the alarm pheromone of ants of the genus Crematogaster [1]. Several syntheses of this compound as the racemate and an enantiomer are known [2–6]. However, many of them involve several steps and most are labor-intensive and require costly starting materials. We developed a convenient and effective synthetic pathway for a racemic analog of 1 that was based on our recently proposed regioselective carbonylation of 1-alkenes using Et2Zn and TaCl5 catalyst [7]. The reaction of but-1-ene with Et2Zn in the presence of TaCl5 (Et2Zn–but-1-ene–TaCl5 = 110:100:5; Et2Zn concentration 1.0 mmol/mL in hexane, 20°C, 5 h) formed organozinc compound 2. For this, hexane (20 mL) was cooled to –15°C and treated with but-1-ene (2.25 ml, 20 mmol) cooled to –30°C. Then, the solution was cooled to –15–20°C, treated with Et2Zn (2.25 mL, 22 mmol) and TaCl5 (0.4 g, 1 mmol), heated gradually to room temperature, stirred for 5 h, cooled to –5°C, and treated dropwise with propionylchloride (3, 1.74 mL, 20 mmol) in hexane. All these operations were performed under a dry Ar atmosphere. The resulting reaction mixture was stirred for 2 h and treated with aqueous HCl solution (10%). The resulting 1 was extracted by Et2O (3 50 mL). The extracts were dried over anhydrous MgSO4. The solvent was distilled off. The residue was chromatographed (SiO2, hexane) to afford 1 (2.69 g, 99% pure) in 95% yield based on 3 (Scheme 1). The structure of 1 was proven using IR, PMR, and 13C NMR spectral methods and GC-MS in addition to comparison with an authentic sample [6].

Phylogeny of the Aphnaeinae: myrmecophilous African butterflies with carnivorous and herbivorous life histories

AbstractThe Aphnaeinae (Lepidoptera: Lycaenidae) are a largely African subfamily of 278 described species that exhibit extraordinary life‐history variation. The larvae of these butterflies typically form mutualistic associations with ants, and feed on a wide variety of plants, including 23 families in 19 orders. However, at least one species in each of 9 of the 17 genera is aphytophagous, parasitically feeding on the eggs, brood or regurgitations of ants. This diversity in diet and type of symbiotic association makes the phylogenetic relations of the Aphnaeinae of particular interest. A phylogenetic hypothesis for the Aphnaeinae was inferred from 4.4 kb covering the mitochondrial marker COI and five nuclear markers (wg, H3, CAD, GAPDH and EF1α) for each of 79 ingroup taxa representing 15 of the 17 currently recognized genera, as well as three outgroup taxa. Maximum Parsimony, Maximum Likelihood and Bayesian Inference analyses all support Heath's systematic revision of the clade based on morphological characters. Ancestral range inference suggests an African origin for the subfamily with a single dispersal into Asia. The common ancestor of the aphnaeines likely associated with myrmicine ants in the genus Crematogaster and plants of the order Fabales.

A New Case of Ants Nesting within Branches of a Fig Tree: the Case of Ficus subpisocarpa in Taiwan

Ficus is one of many plant genera involved in interactions with ants. The interaction is however little documented. We show here that ants, belonging mainly to the genus Crematogaster, nest in hollow internodes of young branches of Ficus subpisocarpa, a monoecious fig species studied in Taiwan. The ants feed on the mutualistic fig-pollinating wasps as well as on parasitic non-pollinating fig wasps. Nevertheless fig-wasps may not constitute a sufficient food source to ensure permanent presence of ants on the tree as the ants were observed to be frequently associated with hemipterans such as coccids and aphids. Fig wasps seem to constitute a reliable and sufficient food source on some dioecious Ficus species. On the contrary, in monoecious Ficus species, resident ants have always been observed to tend homopteran in addition to feeding on fig wasps. Frequent fruiting, prolonged fruit ripening period, ramiflory and rapid growth could constitute traits facilitating strong association based on fig-wasps' consumption of the monoecious F. subpisocarpa with ants. Despite these traits, ants were observed to tend hemipterans, and F. subpisocarpa does not seem to have evolved specialized morphological traits to facilitate the association.

(3S,5R)-6-(benzyloxy)-3-methylhexane-1,5-diol in the synthesis of insect pheromones with methyl-branched carbon chain and of amphidinolide L C 7 –C 14 fragment

New building block (3S,5R)-6-(benzyloxy)-3-methylhexane-1,5-diol was obtained, and based thereon new formal syntheses of (Z)-trogodermal, a component of the sex pheromone of smaller tea tortrix and of the alarm pheromone of ants of genus Crematogaster were suggested. A new synthetic protocol for (3S)-5-methyl-5-oxopentyl acetate and (3S)-5-(benzyloxy)-3-methylpentanal, convenient building blocks for insect pheromones designing was developed. A new simple and efficient asymmetric synthesis of C7–C14 fragment of the cytotoxic macrolactone amphidinolide L was carried out.