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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2006.05.027 Byline: Efrain Martinez, Patricia Duque, Marta Wolff Keywords: Forensic entomology; Paramo; Insect succession; Neotropics Abstract: The minimum postmortem interval can be estimated based on knowledge of the pattern of insect succession on a corpse. To use this approach requires that we take into account the rates of insect development associated with particular climatological conditions of the region. This study is the first to look at insect succession on decomposing carcasses in the high altitude plains (Paramo) in Colombia, at 3035m above sea level. Five stages of decomposition were designated with indicator species identified for each stage: Calliphora nigribasis at the fresh stage; Compsomyiops verena at the bloated stage; Compsomyiops boliviana during active decay; Stearibia nigriceps and Hydrotaea sp. during advanced decay and Leptocera sp. for dry remains. A succession table is presented for carrion-associated species of the region, which can be used for estimating time since death in similar areas. Compsomyiops boliviana is reported for the first time in Colombia. Author Affiliation: Grupo interdisciplinario de Estudios Moleculares (GIEM). Universidad de Antioquia. AA, 1226 Medellin, Colombia Article History: Received 8 April 2004; Accepted 10 May 2006

Abstract: Entomological succession and trophic roles of arthropods associated with different stages of carcass decomposition were studied to estimate the post-mortem submersion interval in two freshwater ecosystems in the Colombian Andes, at an altitude of 2614m. Pig carcasses were employed as models placed 68m apart, one in a stream (lotic) and another in an artificial lake (lentic). Decomposition time to skeletal remains was 74 days in the lake and 80 days in the stream. Six phases of decomposition were established: submerged fresh, early floating, floating decay, bloated deterioration, floating remains and sunken remains. A total of 18,832 organisms associated with the carcasses were collected: 11,487 in the lake (four orders, 19 families and 33 species) and 7345 in the stream (eight orders, 15 families and 25 species). Organisms were classified in the following ecological categories: shredders, collectors, predators, necrophagous, sarcosaprophagous and opportunists. Physical and chemical properties of the habitats, such as water temperature, CO2 and conductivity, varied according to rainfall. In the lake, shredders (Coleoptera: Tropisternus sp. and Berosus sp.) and collectors (Diptera: Chironomus sp.) were found to be associated with submerged phases. Predators (Odonata) were only present during the first phases. Coleoptera (Dytiscidae) were found during floating decay and bloated deterioration stages. In the stream, shredders (Hyalella sp.) and collectors (Simulium sp.) were found during all stages, whereas the predator Oxelytrum discicolle was found exclusively during the floating stages, during which body temperature increased in a fashion similar to active decay in terrestrial environments. [Copyright &y& Elsevier]

The first step for a successful use of any insect as indicator in forensic sciences is providing a precise taxonomic identification at species level. Due to morphology-based identification of Sarcophaginae flies (Diptera, Sarcophagidae) is often difficult and requires strong taxonomic expertise, their use as forensic indicators has been limited. Consequently, molecular-based approaches have been accepted as alternative means of identification. Thus, we aimed testing the efficiency of the barcode region of the mitochondrial cytochrome oxidase subunit I (COI) gene for identification of synanthropic flesh flies of several species of the genera Peckia , Oxysarcodexia , Ravinia , and Tricharaea collected in Colombia. The 645-bp fragment of COI was amplified and aligned (215 parsimoniously informative variable sites). We calculated Kimura two-parameter genetic distances and reconstruct a Neighbor-Joining phylogenetic tree. Our Neighbor-Joining tree recovered all species as monophyletic, and confirmed a new species of the genus Ravinia as also indicated by the interspecific genetic divergences and morphological observations. We obtained a 100% of identification success. Thus, the COI barcodes showed efficiency as an alternative mean of identification of species of flesh flies collected on decaying organic matter in Colombia. [ABSTRACT FROM AUTHOR]

• Diversity of carrion-visiting flesh flies of tropical dry forests of Colombia is studied. • Four new species are described and phylogenetically placed in a comprehensive analysis. • New species and records highlight the high flesh fly diversity concentrated in Colombian dry forests. • Taxa studied here were non-synanthropic, except Blaesoxipha (Gigantotheca) wajiira sp. nov. Many flesh flies of the subfamily Sarcophaginae are very competitive carrion visitors and breeders, and several are synanthropic species of medical and forensic importance. The knowledge of these taxa is still limited, which is more noticeable in sub-sampled ecosystems such as the tropical dry forests of Colombia. Four new species, Blaesoxipha (Gigantotheca) wajiira sp. nov., Lepidodexia deborarangoa sp. nov., Oxysarcodexia luriza sp. nov. and Udamopyga iku sp. nov., are described from tropical dry forests in the Colombian departments of Atlántico, Bolívar, Cesar and La Guajira, all collected using Van Someren-Rydon traps baited separately with fermented fruit, decomposing fish and human feces. The species B. (G.) wajiira sp. nov. is probably synanthropic, while the remaining three new species avoid habitats in and around built-up areas. A phylogenetic parsimony analysis based on 222 morphological characters across 121 taxa of flesh flies recovers each new species nested within their respective genus. The subgeneric affiliation of L. deborarangoa sp. nov. within the large and diverse genus Lepidodexia (sensu lato) is inconclusive, and potential issues of relying solely on external morphological characters for generic and subgeneric classifications are highlighted. The species Lepidodexia (Notochaeta) woodi (Lopes), Oxyvinia wicharti (Lopes) and Sarcofahrtiopsis spinetta Mulieri & Dufek are new records for Colombia. COI sequence data are provided for U. iku sp. nov., L. (N.) woodi and O. wicharti. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract: Lysozymes have been described in invertebrates as digestive or immune molecules. We report here the characterization of two novel c-type lysozymes, RpLys-A (EU250274) and RpLys-B (EU250275), isolated from the fat body and digestive tract of immune stimulated Rhodnius prolixus, a major vector of Chagas disease. Transcriptional profiles indicate that the temporal and spatial expression patterns of these two peptides are very different. RpLys-A is expressed predominantly in the midgut after ingestion of Trypanosoma cruzi in a bloodmeal, or after injection of bacteria into the hemocoel. RpLys-B is expressed primarily in the fat body after bacterial injection. Phylogenetic alignments indicate that RpLys-A aligns best with molecules from other hemipterans whose major expression is found in the intestinal tract whereas RpLys-B aligns best with mosquito and tick molecules whose expression is found principally in hemocytes and fat body and whose role has been described as immune-related. These data suggest a differential compartmentalized role of two closely related molecules; one for immunity in the hemocoel and the other for digestion in the midgut. [Copyright &y& Elsevier]

The genus Panstrongylus includes 14 species widely distributed from Mexico to Argentina, some of them with great epidemiological significance as vectors of Chagas disease. We study the karyotype and the male meiotic process of Panstrongylus chinai, P. geniculatus, P. herreri, P. lignarius, P. megistus, P. rufotuberculatus and P. tupynambai. All species present the same sex mechanism (X1X2Y in males and X1X1X2X2 in females) and they also have 20 autosomes, with the exception of P. megistus that only presents 18 autosomes. The analysis of C-banding patterns and meiotic chromosome behaviour show a great level of variability allowing the identification of three clearly differentiated groups. In the first group, we only include P. megistus because of its unusual number of autosomes. The second group includes P. chinai, P. herreri, P. lignarius and P. rufotuberculatus. Their autosomes present terminal heterochromatic regions that appear scattered throughout the nucleus and associated with the sex chromosomes. Actually, P. herreri and P. lignarius can be considered cytogenetically identical. Our results are in agreement with morphological, ecological and molecular data indicating that they should be regarded as the same species. The third group only includes P. tupynambai that shows autosomes without C-positive regions. Panstrongylus geniculatus shares characters will all the three groups. Its karyotypic features are extremely polymorphic depending on their geographic origin. Some populations do not show any heterochromatic regions, while others exhibit few or several heterochromatic blocks. The chromosomal variability observed, together with its wide distribution and phenetic variability, suggest that P. geniculatus is a species complex comprising at least two distinct species.Considering the entire subfamily, the level of cytogenetic variation in Panstrongylus is lower than that observed in Triatoma but considerably more than that of Rhodnius, which is a very homogenous genus in terms of chromosome appearance and behaviour. This would endorse the closer relationship between Panstrongylus and Triatoma, and their divergence from Rhodnius, in accordance with current tribal classification. [Copyright &y& Elsevier]