Sexual size differences and colour polymorphism of Rhynchophorus phoenicis in the Southwest region of Cameroon

A total of 174 specimens of the African palm weevil Rhynchophorus phoenicis (F.) were sampled during 2010, in eight different localities of the Southwest region of Cameroon. Male and female weevils were measured (body length, abdomen length, abdomen width, pronotum length, pronotum width, head size, and length from tip of rostrum to antennal insertion), and the different pronotum patterns are described. Statistical analysis shows that all morphometric parameters correlate with body length in both males and females, and seven pronotum pattern types are identified, three of which are new. African palm weevil adults show sexual dimorphism: abdomen and head size are significantly greater in females, while pronotum length is significantly greater in males. No statistical differences in the frequencies of pronotum pattern types were seen between males and females, or among localities. A significant difference was seen for the abdomen width between two localities

Figs 1–3 in Uroobovella phoenicicola sp. n., a new Uropodina mite (Acari: Mesostigmata) associated with the African palm weevil (Rhynchophorus phoenicis Fabricius, 1801) from Cameroon

Figs 1–3. Uroobovella phoenicicola sp. n. female, holotype (Cameroon): (1) body, dorsal view; (2) ventral view; (3) lateral view.Published as part of Kontschán, Jenő, Tambe, James Tanyi & Riolo, Paola, 2012, Uroobovella phoenicicola sp. n., a new Uropodina mite (Acari: Mesostigmata) associated with the African palm weevil (Rhynchophorus phoenicis Fabricius, 1801) from Cameroon, pp. 593 in African Invertebrates 53 (2) on page 595, DOI: 10.5733/afin.053.0205, http://zenodo.org/record/834297

Application of the secondary structure model of rRNA for phylogeny: D2-D3 expansion segments of the LSU gene of plant-parasitic nematodes from the family Hoplolaimidae Filipjev, 1934

Knowledge of rRNA structure is increasingly important to assist phylogenetic analysis through reconstructing optimal alignment, utilizing molecule features as an additional source of data and refining appropriate models of evolution of the molecule. We describe a procedure of optimization for alignment and a new coding method for nucleotide sequence data using secondary structure models of the D2 and D3 expansion fragments of the LSU-rRNA gene reconstructed for fifteen nematode species of the agriculturally important and diverse family Hoplolaimidae, order Tylenchida. Using secondary structure information we converted the original sequence data into twenty-eight symbol codes and submitted the transformed data to maximum parsimony analysis. We also applied the original sequence data set for Bayesian inference. This used the doublet model with sixteen states of nucleotide doublets for the stem region and the standard model of DNA substitution with four nucleotide states for loops and bulges. By this approach, we demonstrate that using structural information for phylogenetic analyses led to trees with lower resolved relationships between clades and likely eliminated some artefactual support for misinterpreted relationships, such as paraphyly of Helicotylenchus or Rotylenchus. This study as well as future phylogenetic analyses is herein supported by the development of an on-line database, NEMrRNA, for rRNA molecules in a structural format for nematodes. We also have developed a new computer program, RNAstat, for calculation of nucleotide statistics designed and proposed for phylogenetic studiesPeer reviewe