This study identifies the cuticular metatho- racic structures in earless cockroaches that are the ho- mologs to the peripheral auditory components in their sister taxon, praying mantids, and defines the nature of the cuticular transition from earless to eared in the Dic- tyoptera. The single, midline ear of mantids comprises an auditory chamber with complex walls that contain the tympana and chordotonal transduction elements. The cor- responding area in cockroaches, between the furcaster- num and coxae, has many socketed hairs arranged in discrete fields and the Nerve 7 chordotonal organ, the homolog of the mantis tympanal organ. The Nerve 7 chor- dotonal organ attaches at the apex of the lateral ventro- pleurite (LVp), which has the same shape and general structure as an auditory chamber wall. High-speed video shows that when the coxa moves toward the midline, the LVp rotates medially to stimulate socketed hairs, and also moves like a triangular hinge giving the chordotonal or- gan maximal in- out stimulation. Formation of the mantis auditory chamber from the LVp and adjacent structures would involve only enlargement, a shift toward the mid- line, and a mild rotation. Almost all proprioceptive func- tion would be lost, which may constitute the major cost of building and maintaining the mantis ear. Isolation from leg movement dictates the position of the mantis ear in the midline and the rigid frame, formed by the cuticular knobs, which protects the chordotonal organs. J. Morphol. 000:000 - 000, 2005. © 2005 Wiley-Liss, Inc.

Cockroach homologs of praying mantis peripheral auditory system components.

The method reported here was designed to produce paraffin serial sections as thin as 5 microns of insects or other arthropods with a hard cuticle. Heads and abdomens of Apis mellifera, Eristalomyia tenax and Tenebrio molitor were fixed with Schaffer's liquid, dehydrate with 80% ethanol, 90% ethanol, two changes of 100% isopropanol (2 hr each) and 12 hr in a 1:1 mixture of paraffin (58 C melting point) at 60 C. They were molded in paraffin after 12 hr of infiltration under a partial vacuum at 60 C. Large body openings of objects were sealed with paraffin to prevent infiltration of solvents. Thereafter, the outer paraffin was removed manually and with xylene (15 min); the cuticle was rehydrated with 100% isopropanol and 100% ethanol (15 min each). The objects were then treated with Sputofluol (Merck; a mixture of NaOH and NaClO) until they became white or their colorless endocuticle was stainable with aniline blue WS (C.I. 42755) after rinsing in a 50% acetic acid solution (v/v). They were then dehydrated with 100% ethanol and 100% isopropanol (15 min each) and subsequently re-embedded in paraffin. They were molded, sectioned, stained and mounted as usual.

Serial sectioning of insects with hard exoskeleton by dissolution of the exocuticle.

/pdf/spider-brain-morphology-behavior-4vokbtloez.pdf

Spider Brain Morphology & Behavior

Problems of sclerotized chitin: Softening insect cuticle

The neurons in the brain are classified into 2 groups: the ganglionic neuron and the motor neuron A total of 153 motor neurons around the oesophagus in the center of the tick's brain was mapped Among these, cells 26, 27, 28, 29, 34, 35, 67, 68, 85, 86, 95, 96, 98, 102, 104, 106, 108, 124, 130, 92 and 109 are correlated with the movement of right fore leg, and cells 43, 42, 54, 53, 39, 40, 70, 48, 82, 84, 88, 107, 94, 105, 99, 103, 112, 125, 123 with the movement of left fore leg The first 19 neurons among the former group are symmetrical with their counterparts of the latter group except cells 92 and 109 which have no counterparts

Motor neuron map of tropical cattle tick, Boophilus microplus (Canastrini) (Acarina : Ixodidae)☆

This technique can produce serial sections as thin as 5 μ from hard chitin-covered materials of insects or other arthropods. Procedures: Fix with alcoholic Bouin's fluid for 3 hr. Henceforth subject material to partial vacuum in each step to ensure a final proper embedding. Wash with 80% ethanol 2 or 3 times for 2 hr or until the picric acid is largely removed. Dehydrate to 90% ethanol and give 2 changes of n-butanol 2 hr each, and one of a 1:1 n-butanol-paraffin mixture in 56-57° oven for 12 hr. Finally, use 2 baths of pure paraffin, 3 hr each, to complete the infiltration. After the last bath, withdraw the specimen from the paraffin, and remove the superficial paraffin, first mechanically and then with a xylene bath for 4 min. Rinse first with n-butanol, and afterwards with absolute ethanol, 2 min each. The compound eyes are protected with a paraffin covering, the specimen is hydrated with a 1% aqueous solution of detergent for 1 hr and then washed with running tap water. The material is treated with a ...

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Papers

Protective paraffin infiltration of soft tissues in insects to facilitate softening of hard exoskeletons.