Diversity of ants (Hymenoptera: Formicidae) in the University of Kerala Campus, Thiruvananthapuram, India

Survey conducted on the ant diversity in the Kerala University Campus revealed a total 64 species under six subfamilies. Species belonging to the Myrmicinae dominated (51.5%) followed by Formicinae (20.6%), Ponerinae (13.2%), Dolichoderinae (4.4%), Pseudomyrmicinae (4.4%) and Dorylinae (1.5%). Endemic species Camponotus invidus Forel, 1892 , Cardiocondyla parvinoda Forel, 1902, Carebara spinata Bharti & Kumar, 2013 and Tetramorium rossi (Bolton, 1976) were recorded in the campus. Anoplolepis gracilipes (Smith, 1857), Paratrechina longicornis (Latreille, 1802), Monomorium carbonarium Smith 1858, Solenopsis geminate (Fabricius, 1804), Strumigenys membranifera Emery, 1869, Tetramorium bicarinatum (Nylander, 1846) and Hypoponera ragusai (Emery, 1894) (introduced species) were found in the campus. The results showed that the campus is rich in ant diversity. The sites with human interference showed less diversity. A potential new species in the genus Lepisiota was recorded. Trichomyrmex abberans, Carebara spinata, Crematogaster anthracina, Crematogaster biroi and Nylanderia indica are new records.

Interference Competition for Mutualism between Ant Species Mediates Ant-Mealybug Associations

Ant-hemipteran mutualism has been well documented, and many studies have reported the interference competition between ant species for the mutualism. However, little is known on how this interference competition impacts the reciprocally beneficial association. Previous studies demonstrated that the invasive mealybug Phenacoccus solenopsis (Tinsley) has established close mutual relationship with the ghost ant Tapinoma melanocephalum (Fabricius). The sympatric ants, Paratrechina longicornis (Latreille) and Tetramorium bicarinatum (Nylander) were frequently observed to compete for nutrient honeydew produced by P. solenopsis with T. melanocephalum. Herein, we investigated the effects of interference competition between the ant species on the ant-mealybug interactions. Phenacoccus solenopsis benefited from the tending by T. melanocephalum and P. longicornis. Interference competition between T. melanocephalum and P. longicornis interrupted the mutualism, suppressed the trailing activity of both species, but negligibly influenced the parasitism of Aenasius bambawalei Hayat, a solitary endoparasitoid of P. solenopsis. Harmonia axyridis, a predator of P. solenopsis, showed a significant avoidance when encountering with T. melanocephalum or P. longicornis, but not T. bicarinatum. Ant workers showed higher aggressiveness and lower exploratory activity when T. melanocephalum encountered P. longicornis. However, competition between T. melanocephalum and T. bicarinatum seldom influenced the trailing and exploratory activity of T. melanocephalum. It is concluded that interference competition for mutualism between ant species can mediate ant-mealybug associations and the fitness of mealybug colony. Our results also demonstrate that the effects of interference competition between ant species on ant-mealybug mutualism are varied among ant species.

DNA barcoding of aphid-associated ants (Hymenoptera, Formicidae) in a subtropical area of southern China

As one of the most abundant and complex groups of terrestrial insects, ants have associations with many other organismal groups, such as hemipteran insects producing honeydew. With the aim of expanding the knowledge base of ant species associated with aphids, this study analyzed mitochondrial COI barcodes of 301 ant samples for 37 aphid-associated ant species in a subtropical area of southern China. Sequence analyses revealed that the intraspecific and interspecific distances ranged from zero to 7.7%% and 0.2 to 31.7%, respectively. Three barcoding approaches – Automatic Barcode Gap Discovery, Bayesian Poisson Tree Processes and Generalized Mixed Yule-coalescent – were used to help delimit ant species based on COI sequences, and their results corresponded well with most of the morphospecies. All three approaches indicate cryptic diversity may exist within Tetramorium bicarinatum and Technomyrmex albipes, with intraspecific genetic distances of 7.7% and 6.24%, respectively. Our analyses also reported five species for the first time from Fujian Province of China, and the COI sequences of nine species are newly added into the GenBank. This study provides information about species diversity of aphid-associated ants in subtropical China and compiles a DNA barcode reference library for future ant barcoding work.

First survey of ground-dwelling ants (Hymenoptera: Formicidae) on the uninhabited Gaja-jima Island, the Ryukyu archipelago, Japan

The ground-dwelling ant fauna on the uninhabited Gaja-jima Island, the Tokara Islands, the Ryukyu archipelago, Japan was investigated, which was the first survey on ants of the island. Twenty-three ant species were found during a visit of only eight hours in daytime. Four of them were new records to the Tokara Islands. Of the four new records, the southern limit of distributions was renewed for three species. Three exotic species, Pheidole fervens, Tetramorium bicarinatum, and Tapinoma melanocephalum were recognized, which seems relatively low given that ten exotic species have been altogether recorded from the Tokara Islands. The relationship between invasion by ants and the scale of human activity is discussed.

Invasive ants of continental Ecuador, a first account

El manejo de las especies invasoras es considerado uno de los grandes desafíos que impone el Cambio Global a nuestras sociedades, junto con la deforestación y el calentamiento de la atmósfera. Se conoce muy poco sobre las hormigas invasoras en el Ecuador continental, incluso cuando se ha demostrado en el resto del mundo su agresividad, los impactos negativos en los ecosistemas y las pérdidas económicas que causan. La mayoría de registros de hormigas invasoras en el Ecuador provienen de las Islas Galápagos y no existe un inventario de ellas para el Ecuador continental. Aquàcompilamos registros de hormigas invasoras presentes en la literatura y en colecciones entomológicas locales para crear la primera lista de hormigas invasoras presentes en el Ecuador continental. Se registra la presencia de un total de 16 especies de hormigas invasoras. De estas, diez especies son extranjeras, pero invasoras en el Ecuador; y seis especies son nativas en el Ecuador e invasoras en el exterior. Proveemos los primeros registros para Ecuador continental de Cardiocondyla minutior, Monomorium floricola, Monomorium pharaonis, Tapinoma melanocephalum, y Tetramorium bicarinatum. Además, los registros de Cardiocondyla wroughtonii y Tetramorium lucayanum son los primeros para el país.

Thermal Tolerances of Three Tramp Ant Species (Hymenoptera: Formicidae)

Tramp ant species present a set of adaptations to their urban habitats, and there is a paucity of knowledge about how they interact with abiotic factors, like temperature. Temperature is well known to interfere with insect activity. The present study evaluated the temperature tolerance of three important tramp ant species: Monomorium floricola ( Jerdon), Monomorium pharaonis (Linnaeus) and Tetramorium bicarinatum (Nylander). Tested temperatures were 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48 and 50.C. Ten repetitions with 20 workers each were done with each temperature and analyzed species. The number of dead workers was recorded every hour over a total of 8 hours. All procedures were done using thermal incubators at relative humidity within 50-95%. Workers of M. pharaonis proved more tolerant to high temperatures (30-50.C) than workers of M. floricola and T. bicarinatum. The higher the temperatures tested, greater was the recorded ant mortality, with temperature 50.C being fatal to all species after 1h of exposition. The least tolerant species to temperatures below 20.C was T. bicarinatum. Low temperatures tested were not fatal to any of the tested species.

Kelimpahan Jenis Semut Di Areal Pemukiman Hutan Lindung Sirimau Kota Ambon

The experiment was conducted at residential areas Sirimau forest with three sampling methods, which were hand collecting, bait trap (sugar and tuna) and pitfall traps from July to September 2011. The study aims to determine abudance of ants in residential areas in Ambon Sirimau Protected Forest areas. The results of study found 16 species of ants in total reaching 14.913. The most dominant types are Odontoponera denticulata, Pheidole megacephala, Technomyrmex albipes, Tetramorium simillimum, Tetramorium bicarinatum, Tapinoma melanocephalum, Paratrechina longicornis and Anoplolepis gracilipes. Total abudance of ants is 2.789 classified as moderate by spread of number of individual spread and of community stability. The abudance of ants is strongly influenced by light intensity, temperature, humidity, wind, water and season. Difference of temperature micro, light climate, humidit, interspecific competition, availability of variety of food sources, habitat quality and human activities also affect the abudance of ants. Another finding showed invasive ants, they were Soleonopsis geminate, Paratrechina longicornis and Anoplolepis gracilipes. Keywords: Abudance of ants, invasive species, protected areas, settlement areaAbstrakPenelitian dilaksanakan pada areal pemukiman dalam Hutan Lindung Sirimau dengan tiga metode pengambilan sampel yakni hand collecting, bait trap (umpan gula dan ikan tuna) dan pitfall trap dari bulan Juli hingga september 2011. Penelitian bertujuan mengetahui keragaman semut pada areal pemukiman dalam kawasan Hutan Lindung Sirimau Ambon. Hasil penelitian menemukan adanya 16 jenis semut dengan total individu mencapai 14.913. Jenis–jenis yang sangat dominan dalam kawasan yakni Odontoponera denticulata, Pheidole megacephala, Technomyrmex albipes, Tetramorium simillimum, Tetramorium bicarinatum, Tapinoma melanocephalum, Paratrechina longicornis dan Anoplolepis gracilipes. Total keragaman jenis semut 2.789 tergolong sedang dengan penyebaran jumlah individu semut dan tingkat kestabilan komunitas sedang. Keragaman semut dipengaruhi oleh intensitas cahaya matahari, suhu, kelembaban, angin, air dan musim. Diduga perbedaan suhu mikro, iklim, cahaya, kelembaban, pola makan, kompetisi interspesifik, variasi ketersediaan sumber makanan, kualitas habitat dan aktivitas manusia yang memengaruhi keragaman semut dalam areal pemukiman hutan lindung Sirimau Ambon. Ditemukan 3 jenis semut yang invasif yakni Soleonopsis geminate, Paratrechina longicornis dan Anoplolepis gracilipes. Kata kunci: Kelimpahan semut, spesies invasif, hutan lindung, tipe penggunaan lahan pemukiman