The littoral sea cucumbers (Echinodermata: Holothuroidea) of Guam re-assessed - a diversity curve that still does not asymptote

The Micronesian island of Guam has been an important site for the study of littoral tropical holothuriantaxonomy for almost 200 years. Despite substantial attention by both expeditions and resident taxonomists, new records arestill regularly added to the fauna, demonstrating the challenge of documenting even such large and well-known animals ina small hyper-diverse area. Guam is the type locality of species described by Quoy & Gaimard (1833) and Brandt (1835).A survey of the sea cucumber fauna by Rowe & Doty (1977) led to one of the most used guides for the identification oftropical Pacific sea cucumbers because of the color illustrations of living animals it presented. Focus on echinodermsincluding holothurians continued with numerous new records added in the following decades. Paulay (2003a) summarizedthe fauna last, recording 46-47 species. At this stage the fauna was thought to be well documented. A week-long workshopon holothurian systematics sponsored by the National Science Foundation PEET (Partnerships for Enhancing Expertise inTaxonomy) project in 2010 included a substantial field work component, sampling both during the day and night, withsnorkeling and SCUBA, across a variety of habitats. This survey yielded 40 species, including numerous new records andeven species. Further sampling by Kerr’s lab since the workshop has added additional records. The littoral holothuroidfauna of Guam now comprises 65 species in 17 genera and 7 families. Half of the 19 newly recorded species are the resultof unravelling cryptic species in complexes, the other half are based on new collections. Eleven species are known fromsingle specimens, suggesting that much still remains to be learned about the fauna

Specific detection of fungal pathogens by 18S rRNA gene PCR in microbial keratitis

<p>Abstract</p> <p>Background</p> <p>The sensitivity and specificity of 18S rRNA polymerase chain reaction (PCR) in the detection of fungal aetiology of microbial keratitis was determined in thirty patients with clinical diagnosis of microbial keratitis.</p> <p>Methods</p> <p>Corneal scrapings from patients were used for Gram stain, culture and PCR analysis. PCR was performed with primer pairs targeted to the 18S rRNA gene. The result of the PCR was compared with conventional culture and Gram staining method. The PCR positive samples were identified by DNA sequencing of the internal transcribed spacer (ITS) region of the rRNA gene. Main outcome measures were sensitivity and specificity of PCR in the detection of fungus in corneal keratitis.</p> <p>Results</p> <p>Combination of microscopy and culture gave a positive result in 11 of 30 samples of microbial keratitis. PCR detected 10 of 11 samples that were positive by conventional method. One of the 19 samples that was negative by conventional method was positive by PCR. Statistical analysis revealed that the PCR to have a sensitivity of 90.9% and specificity of 94.7% in the detection of a fungal aetiology in microbial keratitis.</p> <p>Conclusion</p> <p>PCR is a rapid, sensitive and useful method to detect fungal aetiology in microbial keratitis.</p