Molecular and morphometric systematics of Diapterus (Perciformes,Gerreidae)

The fish belonging to Gerreidae are common representatives of the coastal ichthyofauna of the tropics and subtropics of the world. The genus Diapterus has a neotropical distribution and currently includes four species: two in the Atlantic Ocean [Irish mojarra D. auratus Ranzani 1842 and rhombic mojarra D. rhombeus (Cuvier 1829)] and two in the Pacific Ocean [short‐beaked mojarra D. brevirostris (Sauvage 1879) and golden mojarra D. aureolus (Jordan & Gilbert 1882)]. This genus has uncertain taxonomy based on the remarkable and dissimilar morphology of D. aureolus. We evaluated the taxonomy and phylogeny of Diapterus with statistical (canonical discriminant analysis) and phylogenetic analyses (maximum parsimony, maximum likelihood and Bayesian inference) of geometric morphometric data (relative warps) and molecular data (12Sr RNA, 16Sr RNA, COI and RAG1 sequences). Our results indicate that the genus Diapterus as we currently conceive it is a polyphyletic group: [(Gerres cinereus – Eucinostomus spp. (D. aureolus – (Eugerres spp. (D. auratus – (D. brevirostris – D. rhombeus)))))]. Therefore, a taxonomic rearrangement is needed. To preserve the monophyly of the group, our proposal is to remove D. aureolus and place it in a new monotypic genus. A neotype is designated for D. aureolus as well as an artificial identification key for the genera and the species treated in this article.     

Exploration for native parasitoids of Asian longhorned beetle in China as prospective biological control agents

1. Native to China and the Korean Peninsula, the Asian longhorned beetle (ALB) Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) is a high-risk invasive pest of hardwood trees.
2. To explore the potential of biological control of ALB in the United States, we conducted surveys of ALB parasitoids using sentinel logs in five geographical regions (Beijing, Gansu, Guizhou, Shanghai, and Yunnan) in China from 2019 to 2022.
3. Seven hymenopteran larval parasitoid species, Bracon planitibiae Yang, Eurytoma chinensis Yang, Heydenia sp., Oxysychus glabripennis Yang, Sclerodermus guani Xiao et Wu, Spathius anoplophorae Yang, and Zolotarewskya anoplophorae Yang, were collected in Beijing. Four, three and two of these species were also found in Shanghai, Guizhou, and Yunnan, respectively. No parasitoid was found in Gansu.
4. Mean parasitism rates by all parasitoid species were 3.6%–15.8% in Beijing, 1.4%–16.4% in Guizhou, 1.6%–7.1% in Shanghai, and 5.8% in Yunnan.
5. Spathius anoplophorae and O. glabripennis were the two most dominant parasitoids collected consistently in the four different regions and may be considered as prospective agents for biological control introduction against ALB in the United States.
6. We discuss some underlying ecological mechanisms that might contribute to the rarity of egg parasitoids and future opportunities and challenges for biological control of ALB.

     

Prevalence and Concentration of Non-tuberculous Mycobacteria in Cooling Towers by Means of Quantitative PCR: A Prospective Study

There is an increasing level of interest in non-tuberculous mycobacteria (NTM) due to the increasing reported rates of diseases caused by them. Although it is well known that NTM are widely distributed in the environment it is necessary to identify its reservoirs to prevent possible infections. In this study, we aimed to investigate the occurrence and levels of NTM in cooling towers to provide evidences for considering these settings as possible sources of respiratory infections. In the current study, we detected and quantified the presence of NTM by means of a rapid method in water samples taken from 53 cooling towers of an urban area (Barcelona, Spain). A genus-specific quantitative PCR (Q-PCR) assay with a quantification limit (QL) of 500?cells?l^?1 was used. 56% (30) of samples were positive with a concentration range from 4.6?×?10³ to 1.79?×?10⁶?cells?l^?1. In some cases (9/30), samples were positive but with levels below the QL. The colonization rate confirmed that cooling towers could be considered as a potential reservoir for NTM. This study also evaluated Q-PCR as a useful method to detect and quantify NTM in samples coming from environmental sources.     

Simulating Mediterranean landscape pattern and vegetation dynamics under different fire regimes

In the Mediterranean Basin, landscape patterns are strongly human-modified. In recent decades, because of industrialisation and rural exodus, many fields have been abandoned, generating changes in the landscape pattern. In this framework, I aim to study the effect of landscape pattern on landscape dynamic processes in the Mediterranean Basin using simulation models and considering that fire may interact with landscape pattern. First I generate a gradient of five artificial random landscapes. In each landscape I include four species types growing in the Mediterranean Basin, each type with different plant traits (Quercus, Pinus, Erica and Cistus types). In each landscape scenario, each species covers 30% of the landscape but with a different spatial distribution, from the coarsest-grained (L1) to the finest-grained (L5). Then, the dynamics of each of these five landscapes were simulated for 100 years using the FATELAND simulation model. Simulations were run with six fire regime scenarios in each landscape scenario (no fire, mean fire interval of 80, 40, 20, 10 and 5 years). Landscape attributes were computed for the initial and the final landscapes. As expected, the results suggest that, as expected, some species increase and others decrease depending on the fire regime. However, the results also show that different landscape structures produce different dynamics and thus that there is a clear interaction between landscape pattern and fire regime. For instance, coarse-grained spatial patterns generate slower dynamics than fine-grained patterns, and fire-sensitive species are maintained longer under coarse-grained patterns (i.e., fragmentation accelerates extinction of fire-sensitive species).A draft version of this paper was presented at the Special Symposium “Global Change and Landscape Fires” held during the IALE World Congress, in Darwin, Australia, 13–17 July 2003.     

Sexual dimorphism in neuromuscular junction size on a muscle used in courtship by green anole lizards.

The green anole lizard exhibits seasonal courtship behavior that is sexually dimorphic. This courtship consists of the extension of a bright red throat fan (dewlap) associated with head-bobbing display behavior. While males extend their dewlaps in aggressive encounters as well as in courtship, females use their considerably smaller dewlaps much less frequently and mainly in agonistic encounters. In parallel, a number of components of the neuromuscular system controlling dewlap extension are greater in males than in females during the breeding season, including dewlap motoneuron soma size and muscle fiber size and number. These features do not seem to change substantially in adulthood, despite a dramatic decline in dewlap use during the nonbreeding season. We explored the morphology of this neuromuscular system in more detail in the present experiment in males and females during both the breeding and nonbreeding seasons. Fiber and whole muscle length (approximately perpendicular to the fibers) were measured. Acetylcholinesterase histochemistry was used to visualize neuromuscular junctions (NMJs), and the surface area and density of NMJs were assessed for each animal. During the breeding season, NMJ size was larger in males than in females, but NMJ density along each fiber was equivalent between the sexes. In addition, whole muscle length and that of individual muscle fibers, was larger in males than in females. However, when corrected for body size, the sex difference in muscle fiber length disappeared. In the nonbreeding season, the sexual dimorphisms were maintained, suggesting that these features do not change substantially due to differences in circulating testosterone or a difference in use across seasons. Overall, these results are consistent with the idea that enhanced NMJ size is a relatively stable feature of the dewlap muscle in adulthood that either facilitates or is a consequence of using a larger muscle to extend a bigger dewlap in males compared to females.