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Native to East Africa, the giant African snail Lissachatina [= Achatina ] fulica (Bowdich, 1822) is a tropical crop pest and one of the world's top 100 invasive species. It is now present in at least 52 countries worldwide, with an actively expanding range. Lissachatina fulica was first introduced to India in 1847, but subsequent arrivals in India and local patterns of spread remain unclear. This study uses the 16S rRNA gene to identify the extent of genetic variation in India by sampling Indian populations and comparing them with published sequence data. A total of 307 snails were collected from 178 localities in India and from a single locality in the UAE, and the 16S rRNA gene was amplified and sequenced. Eight haplotypes were identified from India of which four are newly recognized. The new haplotypes identified in this study have increased the number of L. fulica 16S rRNA haplotypes from 19 to 23. Examination of haplotype and nucleotide diversities revealed that genetic variation is low in India, the UAE and across Asia as a whole. The number of haplotypes was higher in India when compared to other invasive regions but all of the Asian haplotypes appear to be closely related to the most common haplotypes in the Indian Ocean Islands. Heavy trade between the snail-infested and native-range countries suggests that the variation observed in India might be traced back to its native range, but the lack of sampling and paucity of sequences from East Africa currently prevents a comparison. Tracing back the emergent haplotypes by additional sampling could throw more light on the spread of L. fulica. [ABSTRACT FROM AUTHOR]

The article presents the discussion on giant African snail Lissachatina fulica reported as a pest in rubber plantations adjoining forest fringes in the Western Ghats region of Kerala. Topics include acting as an intermediate host of the rat lung worm Angiostrongylus cantonensis causing eosinophilic meningitis in humans especially children; and snails being found to be in huge numbers and feeding on latex secreted from rubber trees causing damage.

The rapidly spreading Giant African Snail Lissachatina [= Achatina ] fulica (Bowdich, 1822) has been introduced to many parts of the world since the 1800s and is one of the world's most invasive species. We compared cytochrome oxidase subunit I (COI) sequences from four invasive ranges: India, United Arab Emirates (UAE), China and West Africa. Sixteen distinct haplotypes were identified, with nine found in India, four in the UAE, one in China and four in West Africa. Haplotype 5 was the most common haplotype in Asia and haplotype 1 the most common in West Africa. Network analysis suggests that all haplotypes in India, the UAE, China and West Africa were derived from the most common haplotype 5 which is present in all three invasive ranges in Asia. Higher levels of genetic variation were observed in the invasive ranges of Asia than in West Africa. The high genetic variation observed in Asia, together with high levels of trade as exemplified by wood import data, supports the hypothesis that there could have been multiple invasion events in India and the UAE. Additional sampling from the native and invasive ranges in Africa and from other regions of invasion is essential for understanding the movement and spread of L. fulica. [ABSTRACT FROM AUTHOR]

Studies on invasive plants focus on their biology with little knowledge over socio-political reasons for invasions. The increasing realization that the socio-political scenario favoring invasion is the primary cause of biological invasion has changed the perception and facilitates to identify policies and pathways alterations which are needed to prevent future invasions. This study attempts to explain the social dimensions of invasion of two major invasive plants of Kerala—Lantana camara and Chromolaena odorata. Different literatures—books, journals, popular articles, state manuals, state reports, checklists and personal communications were referred to identify the socio-political reasons for the introduction of these species. The study identified that the solemnity of British to exchange and introduce plants across their empire through Agri-horticultural societies, Botanical Gardens and missionaries provided beneficial situations for the purposeful introduction of L. camara to the Calcutta Botanical Garden, India from London. The study also identified species introduction to the Lalbagh Botanical garden, Bangalore from Sri Lanka. These circumstances also led to the accidental introduction of C. odorata to the Calcutta Botanical Garden along with intentionally introduced plants. Lantana camara was reported from Kerala in 1872 indicating its spread facilitated by the admixture of various agents- missionaries, shifting cultivation, linear intrusions, botanical gardens, human movements and birds. The need of survival during Second World War led to the accidental introduction of C. odorata to Kerala from Assam along with the labourers returning from war. Circumstances during the war period led to the movement of people from Kerala to Assam, Sri Lanka and other War participating countries as labourers and militants. [ABSTRACT FROM AUTHOR]

The presence of the body colour polymorphism in the tropical invasive pest giant African snail is reported for the first time from South India. Three different body colour polymorphs were recognised viz. grey, black and white. The grey body colour is the most common polymorph. The black and white colour polymorphs are found to be in almost equal proportions in the reported localities with the grey counterparts. The cytochrome oxidase subunit I (COI) sequences of the three colour polymorphs are found to be identical. The presence of the body colour polymorphism in south India may be attributed to the avian predation and other selection pressures. [ABSTRACT FROM AUTHOR]

Background: The Teak defoliator (Hyblaea puera) is a pest moth of teak woodlands in India and other tropical regions (e.g. Thailand) and is of major economic significance. This pest is of major concern as it is involved in complete defoliation of trees during the early part of the growing season. Defoliation does not kill teak trees, but it results in huge amount of timber loss. Teak defoliator outbreaks are a regular annual feature in most teak plantations in India and it is extremely difficult to predict the exact time and place of occurrence of these outbreaks. Evidence from the study of the population dynamics of H. puera indicated habitual, short range movements of emerging moth populations, suggesting that these populations have spread to larger areas, generation after generation, affecting the entire teak plantations. We were therefore interested in investigating the temporal and spatial relationship among various population groups in Nilambur, Kerala (India) and address the cause of outbreak at the landscape level. Results: The populations were classified into 'endemic', 'epicenter' and 'epidemic' populations based on the time of occurrence and size of infestation. We devised a novel method of screening nuclear and mitochondrial DNA polymorphisms using Randomly Amplified Gene Encoding Primers (RAGEP). We have used this method extensively to evaluate the species specificity, reproducibility and to discriminate among the three different characterised populations of teak defoliator. Conclusions: This method also allowed us to comment with some certainty that the endemic teak defoliator, H. puera do not play a major role in contributing to large-scale infestations. With respect to the hypotheses put forward regarding the origin of outbreaks of the moth, this study confirms the role of migration in outbreak causation, while negating the belief that endemic populations aggregate to cause an epidemic. [ABSTRACT FROM AUTHOR]