38 research outputs found
Comparative analysis and systematic mapping of the labial sensilla in the nepomorpha (Heteroptera: Insecta)
The present study provides new data concerning the morphology and distribution of the labial sensilla of 55 species of 12 nepomorphan families (Heteroptera: Nepomorpha) using the scanning electron microscope. On the labial tip, three morphologically distinct types of chemosensilla have been identified: two types of papillae sensilla and one type of peg-in-pit sensilla. Twenty-one morphologically distinct types of the mechanosensilla as well as two types of the trichoid sensilla (contact-chemoreceptive sensillum) have been identified on all labial segments in representatives of subfamilies. In Nepomorpha, morphological ground plan of the labial sensory structures is represented by an apical sensory field with 10-13 pairs of papillae sensilla and the peg-in-pit ones placed more laterally; numerous trichoid sensilla are placed on the IV segment; the chaetica sensilla are present and placed in groups or rows distributed along the labium near the labial groove on the dorsal side, and also several chaetica sensilla are unevenly scattered on the surface of that segment; the cupola and peg sensilla are numerous and evenly scattered on the fourth labial segment; the prioprerecptive sensilla, one pair is positioned on the dorsal side and on the fourth segment of the labium. The new apomorphical characters have been established for the labial sensilla in the Nepomorpha
Deliberations on the external morphology and modification of the labial segments in the nepomorpha (heteroptera: Insecta) with notes on the phylogenetic characteristics
The present study provides new data concerning the external morphology of the labial segments of 46 species from nine Nepomorpha families using the scanning electron microscope. The labial segments are described in detail and images of their structures are presented for the systematic groups. Subsequent segments of the labium (I, II, III, and IV) are shaped similarly in all investigated taxa but carry individual characters in some (sub-)families. Five morphologically distinct forms of the apical plate and five intercalary sclerites have been identified. Additionally, three types of the articulation on the dorsal side between the third and second segments are interpreted as the new characters. The presence of the midventral condyle on the distal edge of the first segment and the third segment has been reanalyzed. New position of the midventral condyle on the proximal edge of the fourth labial segment has been distinguished in several groups. The new set of characters has been estimated from the plesiomorphic taxa of the Nepoidea (Nepidae and Belostomatidae) and subsequently through the more advanced taxa in the relation to the outgroup (Gerromorpha). The evaluation of these characters has revealed twenty-seven new apomorphies for the labium in the Nepomorph
The phylogenetic information carried by a new set of morphological characters in planthoppers : the internal mouthpart structures and test in the Cixiidae model (Hemiptera: Fulgoromorpha)
Internal morphological structures of Cixiidae
mouthparts are described and compared in various representatives
of the Cixiidae and several other representatives
of hemipterans. The morphological study shows that the
mouthpart structures have not evolved uniformly and
reveals the great disparity of these structures. Particularly,
the connecting system of the mouthparts, localisation of
salivary canal and shape of the mandibular and maxillar
stylets provide together a new set of 17 new characters. A
parsimonious analysis to evaluate the phylogenetic interest
carried by these 17 selected characters shows that mouthpart
structures have not evolved anarchically, but that they
indeed carry some phylogenetic information that will be
useful to be included in further morphological phylogenetic
analysis
Antennal sensory structures in water bugs of Nepoidea (Insecta: Hemiptera: Nepomorpha), their morphology and function
The Nepoidea superfamily belongs to the water bugsā infraorder (Nepomorpha) and consists of two familiesāBelostomatidae
and Nepidae. Species from those families are the largest of all nepomorphans and are considered to be top predators
in aquatic ecosystems. A characteristic feature of the group is the existence of short antennae concealed in grooves behind
the eyes, which is an adaptation to the water habitat. The antennae bear many types of sensillar structures, which receive
signals from the environment. Among such structures, mechanosensilla were of the greatest diversity. The antennal sensilla
of species from both families were examined under the scanning electron microscope. 11 essential morphological types of
sensilla were distinguished, including 5 new mechanosensilla types (sensilla paddle-like, cone-like, squamiformia, brush-like
and club-like). Basal types of mechanosensilla such as trichodea, chaetica, basiconica (subtype 1) and campaniformia occur
in Nepoidea and other Heteroptera. In some representatives of both families, sensilla paddle-like and sensilla basiconica
type 1 were observed. Moreover, sensilla chaetica and cone-like were found in some species of Belostomatidae, whereas in
Nepidae sensilla squamiformia, brush-like and club-like were observed. Apart from mechanosensilla, one type of thermohygrosensilla
(ampullacea) and two different shaped olfactory sensilla basiconica (subtypes 2, 3) and coeloconica (subtypes
1, 2, 3) were found. It could indicate sensilla use in the identification of the water reservoirs and locating prey
Morphology and distribution of the external labial sensilla in Fulgoromorpha (Insecta: Hemiptera)
The present paper describes the sensory structures
on the apical segment of the labium in fifteen fulgoromorphan
families (Hemiptera: Fulgoromorpha), using
the scanning electron microscope. Thirteen morphologically
distinct types of sensilla are identified: five types of
multiporous sensilla, four types of uniporous sensilla and
four types of nonporous sensilla. Three subapical sensory
organ types are also recognized, formed from one to several
sensilla, each characteristic of a family group. Sensilla
chaetica (mechanoreceptive sensilla) fall into three categories
dependent on length and are numerous and evenly
distributed on the surface of the labium except where they
occur on specialized sensory fields. The planthopper morphological
ground plan is represented by two apical pair of
sensory fields (dorsal and ventral) on which 11 dorsal pairs
of sensilla (10 peg-like pairs ? 1 specialized pair dome or
cupola-like) and 2 ventral pairs of sensilla basiconica
occur. Two main patterns (cixiid and issid) together with
more specialized ones (derbid, lophopid, flatid and fulgorid)
are reported. Disparity and diversity of the sensory
structures are analyzed from a taxonomic and functional
perspective. A gustatory function is provided for several
chemoreceptive labial sensilla, as in the antennal flagellum
sensilla in some other Hemiptera. This represents a more
recently evolved function for the planthopper labium.
Finally, further lines of study are suggested for future work
on the phylogeny of the group based on the studied
characters
Phylogenetic Signals from Nepomorpha (Insecta: Hemiptera: Heteroptera) Mouthparts: Stylets Bundle, Sense Organs, and Labial Segments
The present study is a cladistic analysis of morphological characters focusing on the file of the mandible, the apices of the maxillae, the rupturing device on the maxillae, the internal structures of the mouthparts, and the external morphology of the labial segments as well as the distribution of labial sensilla in true water bugs (Hemiptera: Heteroptera, infraorder Nepomorpha). The study is based on data referring to sixty-two species representing all nepomorphan families (Heteroptera), together with one outgroup species representing the infraorders Gerromorpha (Mesoveliidae). The morphological data matrix consists of forty-eight characters. The present hypothesis supports the monophyly of the Nepomorpha and the monophyly of all families. The new modification in the systematic classification has been proposed: ((Nepidae + Belostomatidae), (Diaprepocoridae + Corixidae + Micronectidae), (Ochteridae + Gelastocoridae), Aphelocheiridae, Potamocoridae, Naucoridae, Notonectidae, and (Pleidae + Helotrephidae))
Description of the oviparous female and new information on the biology of the rare aphid Stomaphis radicicola Hille Ris Lambers 1947 (Hemiptera, Aphidoidea)
Information is provided concerning the discovery of the rare aphid species Stomaphis radicicola H. R. Lambers in Slovakia. The first description of the oviparous morph is given and its morphological resemblance to S. bratislavensis Czylok et Blackman is discussed. Supplementary data concerning the molecular identity and biology of S. radicicola is presented
Morphological study of the labial sensilla in Nabidae (Hemiptera: Heteroptera: Cimicomorpha)
The study presents new data on the morphology and distribution of the labial tip sensilla of six species of two nabid subfamiliesā
Protosteminae and Nabinae (Heteroptera: Cimicomorpha), which were obtained using a scanning electron microscope.
In both taxa, there are five morphologically distinct types of sensilla on the tip of the labium: peg sensilla with a terminal pore,
nonporous peg sensilla, elongated placoid sensilla with wall pores (multiporous), and trichoid sensilla. In addition, oval plate
sensilla with a terminal pore (Tp-opls) were observed in the genus Himacerus. Campaniform sensilla and nonporous chaetic
sensilla were observed on the surface of the last segment of the labium in all of the studied species. Over a dozen trichoid
sensilla were scattered on the last segment of the labium only in the genus Prostemma. Based on their external structure, it
is likely that these sensilla are chemosensitive and mechanosensitive. The oval plate sensilla with a Tp-opls (gustatory) in
Himacerus (Nabinae) represent a morphological novelty that probably evolved independently of other nabids
Morphological Disparity of the Mouthparts in Polyphagous Species of Largidae (Heteroptera: Pentatomomorpha: Pyrrhocoroidea) Reveals Feeding Specialization
Mouthpart structures were observed in four species of Largidae using scanning electron
microscopy to investigate their morphological disparity, and linked to changes in feeding
specialization. The examined species are pests that feed mainly on seeds and plant sap of forbs,
shrubs, and trees. Their external mouthparts are described in detail for the first time herein. The
coneālike labrum and fourāsegmented tubeālike labium are shorter in Physopelta species than in
Macrocheraia grandis (Grey). The labium surface in all studied species bears nine types of sensilla
(St1āSt2, Sb1ā3, Sch, Sca1ā2, Sm). The distributions of sensilla on particular labial segments varies
among the studied species. The tripartite apex of the labium consists of two lateral lobes and an
apical plate that is partly divided in Physopelta species, and not divided in Macrocheraia. Each lateral
lobe possesses a sensillar field with 10 thickāwalled uniporous sensilla basiconica, one multiporous
sensillum styloconicum, and one long nonāporous hair sensillum. Each mandibular stylet tip in M.
grandis has a central tooth placed anteriorly and pairs of teeth arranged dorsoālaterally. In
Physopelta, there are one or two central teeth placed anteriorly but two pairs of teeth dorsoālaterally.
In all studied species, the inner surfaces of the mandibular stylets have scaleālike projections. A
leftāright asymmetry of the maxillary stylets is noticeable; the external end of the right maxillary
stylet is smooth and slightly tapered in M. grandis and evidently wider (spoonālike) in the three
species of Physopelta, while the left end of the stylets is straight and narrow in M. grandis in contrast
to Physopelta, in which the end is straight and wide. No differences in the internal structure of the
maxillary stylets were observed among the studied species. Based on structural differences, we
inferred that the mandibles and maxillae are more adapted for seedāsucking in Physopelta species
than in M. grandis. M. grandis has the ends of the maxillae more narrowed, a trait more adapted for
sucking sap from phloem or parenchymal cells
The variability of antennal sensilla in Naucoridae (Heteroptera: Nepomorpha)
The morphology and distribution of sensilla on the surface of the antennae of the naucoridsā species were studied via scanning electron microscopy. Eleven types of sensilla were identified regarding specific sensory modalities, based on their cuticular morphology. Cuticle morphology identifies five types of sensilla trichodea, four types of sensilla basiconica, one type of sensillum coeloconicum and sensillum ampullaceum. Three new types of mechanosensitive sensilla were found. Moreover, the morphological diversity between the antennae allowed the distinction of ten different antennal types that correspond to different sensillar sets. The sensilla found in Naucoridae share similarities with the sensilla of other nepomorphan taxa, as well as of terrestrial insects. However, no sensillar synapomorphy was found between Naucoridae and Aphelocheiridae