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The genus Cenophengus LeConte (1881) includes 27 species, distributed from southern United States to northern Costa Rica. In order to test the monophyly of Cenophengus, a cladistic analysis based on 81 morphological characters, 28 species of Cenophengus and 27 outgroup species was conducted. A clade supported by three synapomorphies corresponds to Cenophengus as a monophyletic group according to the relationships obtained under both equaland implied weights. The systematic relevance of the coding of the characters from the wing is discussed and the sequence of the character state transformations for the veins (radial twenty [r3], posterior radial twenty [RP] size, and anterior cubital veins [CuA]) is optimized in the cladogram obtained under implied weights. Cenophengus species are distributed in the Nearctic and Neotropical regions, and particularly in the Mexican Transition Zone, where their greatest diversity is found.

Antecedentes y Objetivos: Loganiaceae es un grupo de plantas tropicales que se han estudiado escasamente en México. Algunos de sus taxones son poco conocidos en cuanto a su taxonomía y distribución, como el caso del género Mitreola, en el que además algunas de sus especies tienen problemas nomenclaturales. Este trabajo presenta una revisión taxonómica de Mitreola petiolata y resuelve los problemas nomenclaturales que ha tenido a lo largo de los años.Métodos: Se revisaron especímenes en diferentes herbarios, literatura especializada para la obtención de descripciones y claves taxonómicas, número de especies del género y su distribución; así como la circunscripción y problemas nomenclaturales del taxon. Para la obtención de los datos palinológicos, se acetolizó material de flores maduras y se revisó en el microscopio electrónico de barrido. A partir de los datos obtenidos se obtuvo una evaluación de la situación de conservación.Resultados clave: Mitreola petiolata tiene una distribución pantropical y es la única especie del género presente en el país. La especie se extiende desde Tamaulipas y Sinaloa hasta la Península de Yucatán. A pesar de la variación morfológica de estructuras como las hojas o los lóbulos de la cápsula, los caracteres de importancia taxonómica (inflorescencias dicotómicas, flores subsésiles y estambres insertos cerca de la base de la corola) se mantienen constantes. Se proporciona una revisión para M. petiolata, una clave dicotómica, datos sobre su distribución y estado de conservación en el país. Se presenta información detallada sobre la micromorfología de los granos de polen, la primera hecha para la especie. Se sugiere la categoría de preocupación menor por su amplia distribución.Conclusiones: La constante revisión y curación de las colecciones biológicas mantiene actualizado el conocimiento de los taxones. Tal es el caso de M. petiolata, para la cual se proporciona una actualización de su sistemática, distribución y estado de conservación.

Helopini is a diverse tribe in the subfamily Tenebrioninae with a worldwide distribution. The New World helopine species have not been reviewed recently and several doubts emerge regarding their generic assignment as well as the naturalness of the tribe and subordinate taxa. To assess these questions, a preliminary cladistic analysis was conducted with emphasis on sampling the genera distributed in the New World, but including representatives from other regions. The parsimony analysis includes 30 ingroup species from America, Europe and Asia of the subtribes Helopina and Cylindrinotina, plus three outgroups, and 67 morphological characters. Construction of the matrix resulted in the discovery of morphological character states not previously reported for the tribe, particularly from the genitalia of New World species. A consensus of the 12 most parsimonious trees supports the monophyly of the tribe based on a unique combination of characters, including one synapomorphy. None of the subtribes or the genera of the New World represented by more than one species (Helops Fabricius, Nautes Pascoe and Tarpela Bates) were recovered as monophyletic. Helopina was recovered as paraphyletic in relation to Cylindrinotina. One Nearctic species of Helops and one Palearctic species of Tarpela (subtribe Helopina) were more closely related to species of Cylindrinotina. A relatively derived clade, mainly composed by Neotropical species, was found; it includes seven species of Tarpela, seven species of Nautes, and three species of Helops, two Nearctic and one Neotropical. Our results reveal the need to deeply re-evaluate the current classification of the tribe and subordinated taxa, but a broader taxon sampling and further character exploration is needed in order to fully recognize monophyletic groups at different taxonomic levels (from subtribes to genera).

Four new species of Agriotes from Mexico are described and illustrated: Agriotes minutus, A. pedregalensis, A. rhombus, and A. trinotatus.

This paper introduces GLOCSA as a new scoring function to rate multiple sequence alignments. It is intended to be simple, considering the whole alignment at once and reflecting the parsimony of an alignment. Then, a GLOCSA Guided Genetic Algorithm is proposed in order to refine alignments previously generated by MUSCLE. The results so far are depicted in this paper.