The Antennal Sensilla of the Nymph of Ephemera Danica

The antennal rudiments in lepidopterous insects are present as disks during the larval stage. The tubular double-walled antennal disk is present beneath the larval antenna, and its inner layer gives rise to the adult antenna during the pupal stage. The sensilla develop from a cluster of cells that are derived from one stem cell, which gives rise to both sensory and enveloping cells. During the morphogenesis of the sensillum these cells undergo major transformations, including cell death. In the moth Agrotis segetum the pupal stage lasts about 14 days (temperature, 25°C). The antennae, clearly seen from the exterior, were dissected and fixed according to standard procedures (3 % glutaraldehyde in 0.15 M cacaodylate buffer, followed by 1 % osmiumtetroxide in the same buffer). Pupae from day 1 to day 8, of both sexes were studied.

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Morphological Characterization of the Antennal Sensilla of the Afrotropical Sand Fly, Phlebotomus duboscqi (Diptera: Psychodidae)

Journal of Medical Entomology ◽

10.1093/jme/tjaa247 ◽

2020 ◽

Author(s):

Ana Cristina Bahia ◽

Ana Beatriz F Barletta ◽

Luciana Conceição Pinto ◽

Alessandra S Orfanó ◽

Rafael Nacif-Pimenta ◽

...

Keyword(s):

Morphological Characters ◽

Morphological Characterization ◽

Sand Fly ◽

Antennal Sensilla ◽

Olfactory Sensilla ◽

Zoonotic Cutaneous Leishmaniasis ◽

Electrophysiological Studies ◽

Phlebotomus Duboscqi ◽

Well Differentiated ◽

Function Number

Abstract We investigated by scanning electron microscopy the morphology, distribution, and abundance of antennal sensilla of females Phlebotomus duboscqi sand fly, an important vector of zoonotic cutaneous leishmaniasis at Afrotropical region. Thirteen well-differentiated sensilla were identified, among six types of cuticular sensilla. The probable function of these sensillary types is discussed in relation to their external structure and distribution. Five sensillary types were classified as olfactory sensilla, as they have specific morphological characters of sensilla with this function. Number and distribution of sensilla significantly differed between antennal segments. The results of the present work, besides corroborating in the expansion of the morphological and ultrastructural knowledge of P. duboscqi, can foment future electrophysiological studies for the development of volatile semiochemicals, to be used as attractants in traps for monitoring and selective vector control of this sand fly.

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Fine Morphology of Antennal and Ovipositor Sensory Structures of the Gall Chestnut Wasp, Dryocosmus kuriphilus

Insects ◽

10.3390/insects12030231 ◽

2021 ◽

Vol 12 (3) ◽

pp. 231

Author(s):

Milos Sevarika ◽

Marco Valerio Rossi Stacconi ◽

Roberto Romani

Keyword(s):

Ultrastructural Organization ◽

Antennal Sensilla ◽

Dryocosmus Kuriphilus ◽

Transmission Electron ◽

Significant Damage ◽

Sensory Structures ◽

Host Plant Location ◽

Oviposition Sites ◽

Fine Morphology

Dryocosmus kuriphilus is a gall-inducing insect, which can cause significant damage on plants of the genus Castanea Mill., 1754. Antennae and ovipositor are the main sensory organs involved in the location of suitable oviposition sites. Antennal sensilla are involved in the host plant location, while ovipositor sensilla assess the suitability of the ovipositional bud. On both organs, diverse sensillar organs are present. Here, the distribution and ultrastructural organization of the sensilla were investigated by scanning and transmission electron microscopy. The antennae of D. kuriphilus are filiform and composed of 14 antennomeres, with the distal flagellomere bearing the highest number of sensilla. On the antennae, 6 sensilla types were found; sensilla chaetica, campaniformia, coeloconica-I, coeloconica-II, trichoidea and placoidea. The sensilla placoidea and trichoidea were the most abundant types. On the external walls of the ovipositor, gustatory and mechanoreceptive sensilla were observed. Internally, the egg channel hosted two additional sensory structures. The putative functional role of each sensilla in the context of insect’s ecology is discussed as well as the ovipositional mechanism used by this insect.

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On Crepidostomum farionis O. F. Müll. (= Stephanophiala laureata Zeder), a Distome Parasite of the Trout and Grayling. I. The Life History

Parasitology ◽

10.1017/s0031182000005552 ◽

1927 ◽

Vol 19 (1) ◽

pp. 86-99 ◽

Cited By ~ 21

Author(s):

F. J. Brown

Keyword(s):

Life History ◽

Gall Bladder ◽

Excretory Vesicle ◽

Intermediate Hosts ◽

Larval Trematode ◽

Sphaerium Corneum ◽

Two Generations ◽

History Of ◽

Second Intermediate Host ◽

Ephemera Danica

1. Crepidostomum farionis inhabits the gall bladder, as well as the intestine and pyloric caeca, of the trout and grayling.2. The life history of Crepidostomum farionis has been worked out and is based on the similarity of organisation of the cercaria, encysted larval trematode and the adult.3. The first intermediate hosts in the life history of this trematode are Pisidium amnicum (Müll.) and Sphaerium corneum (L.) though the latter is unusual.4. The second intermediate host is the larva of the mayfly, Ephemera danica (Müll.).5. There are two generations of rediae, the first gives rise to daughter rediae, which in turn produce cercariae.6. The rediae are characterised by the absence of ambulatory processes and a functional intestine.7. The cercaria (n.sp.) possesses “eye spots,” stylet and gland cells (salivary?), and the excretory vesicle is tube-shaped.8. The excretory system of the redia and the cercaria has been worked out in detail.9. The relation of the parasites to their respective hosts is discussed. On account of the need for further observations definite conclusions are held over for a later paper.

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