External structures of the metathoracic scent gland efferent system in the true bug superfamily Pyrrhocoroidea (Hemiptera: Heteroptera: Pentatomomorpha). (July 2021)

• Record Type: Journal Article
• Authors: Hemala, Vladimír; Kment, Petr; Tihlaříková, Eva; Neděla, Vilém; Malenovský, Igor
• Is Part Of: Arthropod structure & development. Volume 63(2021)
• Publication Date: 2021-07
• Subjects: Insect thorax -- Spiracle -- Eutrichophora -- Scanning electron microscopy -- Comparative morphology -- Phylogeny; Arthropoda -- Morphology -- Periodicals; Arthropoda -- Anatomy -- Periodicals; Arthropoda -- Cytology -- Periodicals; Arthropods -- growth & development -- Periodicals; 595
• DOI: 10.1016/j.asd.2021.101058
• Languages: English
• ISSNs: 1467-8039

Abstract

Abstract: Pyrrhocoroidea represents an important group of true bugs (Insecta: Hemiptera: Heteroptera) which includes fire bugs, cotton stainers and other taxa widely used in experimental studies or known as pests. However, the morphology and phylogeny of Pyrrhocoroidea have been only poorly studied so far. Here, structures of the external scent efferent system of the metathoracic scent glands are examined in 64 out of 71 currently valid genera of Pyrrhocoroidea and scanning electron micrographs are provided for most taxa. Several characters are revealed which define each of the three higher taxa within Pyrrhocoroidea: Larginae (small auriculate peritreme lacking manubrium and median furrow; metathoracic spiracle never surrounded by evaporatorium), Physopeltinae (large, widely open ostiole; large peritremal disc with manubrium [new term], lacking median furrow; mace-like mycoid filter processes of equal shape and size on both anterior and posterior margins of metathoracic spiracle), and Pyrrhocoridae (elongate auriculate peritreme with deep median furrow). Within Pyrrhocoridae, three main types (A, B and C) of the external scent efferent system are distinguished, differring in the amount of reductions. The findings are interpreted in the context of phylogenetic hypotheses available for Pyrrhocoroidea and their close relatives, Coreoidea and Lygaeoidea. An updated identification key to the families and subfamilies of Pyrrhocoroidea applicable for both sexes is provided. Highlights: External morphology of metathoracic scent glands is documented in most taxa of Pyrrhocoroidea. These structures clearly define higher taxa: Larginae, Physopeltinae and Pyrrhocoridae. Three types of external scent efferent system are distinguished within Pyrrhocoridae. No synapomorphies between Pyrrhocoroidea and Coreoidea or Lygaeoidea were found. An updated identification key to families and subfamilies of Pyrrhocoroidea is provided.