The Spiny Rat Mite Echinolaelaps echidninus (Berlese, 1887) (Dermanyssoidea: Laelapidae): Redescription of the Female with Emphasis on its Gnathosoma, Sense Organs, Peritreme and Pulvilli

摘要

The present Scanning Electron Microscopic (SEM) study includes redescription of female Echinolaelaps echidninus with emphasis on its gnathosoma, sense organs, peritreme and pulvilli which were rarely described in superfamily Dermanyssoidea. Chaetotaxy of dorsal shield revealed 40 pairs of setae, 22 on prosoma and 18 on opisthosoma. Epigynial plate carried 5 pairs of setae. Gnathosoma consisted of long basis capituli carrying median hypostome and 2 lateral pedipalps. Hypostome had dorsal labrum covered with finger-like processes, 2 lateral 3-segmented chelicerae and ventral labium carrying 4 lobulated plates. Function of labrum processes might be chemosensory while labium lobules might be mechanical, preventing solid material from entering the oral cavity. Palpal and foreleg tarsal organs comprised 10 and 16 sensillae, respectively. Sensillae of palpal organ were mostly chemoreceptors while those of tarsal organ were probably mechanoreceptors. Peritremal pit contained 4 rows of hand-like papillae and 5 concentric rows of minute papillae. Each pulvillus terminated with 2 medioventral claws. Pulvillus I had terminal integumental folds while each pulvillus II-IV had 2 lateral comb-like plates. Each plate carried 8-10 processes.