Las curiosas arañas pelícano

Un estudio recientemente publicado en ZooKeys sobre la revisión de las curiosa arañas pelícano ha llevado a éstas a ser virales en las redes sociales. Y es que las arañas del género Eriauchenius y el nuevo género Madagascarchaea tienen todo para llamar la atención, un nombre común llamativo, una apariencia fuera de lo común y endémicas.

En el artículo publicado a principios de enero de 2018 se realizó en Madagascar, zona de donde éstas arañas son endémicas. Se revisaron 20 especies dentro del género Eriauchenius de las cuales 14 son nuevas especies, también se describieron 4 nuevas especies dentro del nuevo género Madagascarchaea que contiene 6 especies en total.

Datos curiosos:

*También son llamadas arañas asesinas
*Existen desde antes de que Pangea se separara, lo que los hace fósiles vivientes
*No construyen telaraña
*Su estructura cefálica le da la apariencia de tener "cabeza y cuello"
*Sólo cazan otras arañas
*Sus quelíceros pueden ser extendidos en un ángulo de 90° para atacar a su presa
*Los nombres de las nuevas especies están dados en honor de figuras importantes en la historia de Madagascar

Aquí les dejo unas fotos de estas extraordinarias criaturas, y como siempre, si quieres leer el artículo completo CLICK AQUI

Araña pelícano alimentándose de otra araña

Eriauchenius andriamanelo 

E. workmani

!Hermosas! ¿no crees?

Phylogenetic Importance of Immature Stages: Solving the Riddle of Exeretonevra Macquart (Diptera: Xylophagidae)

Phylogenetic Importance of Immature Stages: Solving the Riddle of Exeretonevra Macquart (Diptera: Xylophagidae)
CHRISTOPHER M. PALMER AND DAVID K. YEATES

ABSTRACT
Exeretonevra Macquart is a small genus of ßies (Diptera) belonging to the suborder Brachycera endemic to Australia. The classiÞcation of Exeretonevra has been extremely unstable; the genus has been placed in 3 of the 4 brachyceran infraorders at various times since it was described in 1846. Misplacements were a result of reliance on convergent characters of wing venation or plesiomorphic features of the adult. Synapomorphies critical to the classiÞcation of Exeretonevra remained unavailable for 150 yr because the larval stages were unknown. Here we describe egg and larval morphology of Exeretonevra angustifrons Hardy, and provide biological information on these life history stages.Wealso provide a detailed treatment of external anatomy of the adult and describe some aspects of adult biology. Larval characteristics and reinterpretation of adult morphology clearly show that Exeretonevra belongs to the family Xylophagidae, subfamily Coenomyiinae. A scanning electron microscope study of the paired bare areas present posterolaterally on the Þrst abdominal tergite suggests that these areas are associated with, and provide an outlet for, a glandular product. The Xylophagidae is the sole member of the infraorder Xylophagomorpha, which are predominantly distributed in the northern hemisphere. Exeretonevra is the only Australian representative of this infraorder, and this lineage is likely to have existed on the continent since the Mesozoic. The distribution of larval habitats across xylophagid genera suggests at least 2 evolutionary transitions in
the family between soil and rotting wood.

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Genetic Variation in the Myzus persicae Complex (Homoptera: Aphididae): Evidence for a Single Species

Genetic Variation in the Myzus persicae Complex (Homoptera: Aphididae): Evidence for a Single Species
KIERAN M. CLEMENTS, BRIAN M. WIEGMANN, CLYDE E. SORENSON, CLYDE F. SMITH,
PAUL A. NEESE, AND R. MICHAEL ROE1


ABSTRACT
Genetic variation was assessed for the closely related aphids Myzus nicotianae Blackman and Myzus persicae (Sulzer), previously classiÞed as a single species. Populations of both red and green color morphs, collected from tobacco and nontobacco hosts from 3 continents, were analyzed via random ampliÞed polymorphic DNA (RAPD)-polymerase chain reaction (PCR) and mitochondrial cytochrome oxidase II (COII) and elongation factor- 1 alpha (EF-1a) gene sequencing. Three other Myzus speciesÑM. cerasi (F.), M. hemerocallis Takahashi, and M. varians Davidson) Ñwere used as outgroups in our analyses. RAPD-PCR analysis revealed many, easily detectable genetic polymorphisms between the Myzus persicae complex and the outgroup species. The small number of polymorphisms detected within the complex were not correlated with host plant or the geographic origin of populations. The sequences of both COII and EF-1a for all populations within the M. persicae complex were identical, although signiÞcant variation was evident between the M. persicae complex and outgroup taxa. These results strongly suggest the synonymy of M. persicae and M. nicotianae.


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Phylogeny of the Dragonfly and Damselfly Order Odonata as Inferred by Mitochondrial 12S Ribosomal RNA Sequences

Phylogeny of the Dragonfly and Damselfly Order Odonata as Inferred by Mitochondrial 12S Ribosomal RNA Sequences
CORRIE SAUX, CHRIS SIMON, AND GREG S. SPICER

ABSTRACT The phylogenetic relationships among members of the Odonates were inferred from
mitochondrial DNA 12S ribosomal RNA sequence data. These data show support for a monophyletic
Anisoptera suborder, which are consistent with previous phylogenetic work performed on the group.
However, the Zygoptera are paraphyletic based on mitochondrial DNA evidence. In particular, the
family Lestidae appears more closely related to the Anisoptera then the Zygoptera

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