The internal morphology of the adult of Tribolium anaphe Hinton (Coleoptera: Tenebrionidae)

Abstract

SYNOPSISThe internal anatomy of the adult of Triboliurn anuphe is described and compared with that of two other species of Tribolium and one species of the genus Latheticus. The taxonomic importance of certain characters is discussed.THE first description of Tribofium unuphe was given by Hinton in 1948, but not until four years later was the species first recorded in Great Britain (Williams & Brett, 1952). Like most of the other members of the genus Tribolium Macleay, it is a pest of stored food products.In this paper the internal anatomy of the adult of Tribolium unaphe is described and the taxonomic importance of some of the features discussed. INTERNAL ANATOMY (1) Alimentary CanalThe alimentary canal (figs. 1, 2, 3 and 4) of T. unuphe comprises the usual three parts, i.e. fore, mid and hind gut.The fore gut consists of the buccal cavity, the pharynx, the oesophagus, the crop and the gizzard. The buccal cavity (Buc) is that part of the fore gut located immediately behind the true mouth and is guarded on each side by a lightly sclerotised, triangular plate ( p ) . The buccal cavity itself opens into the pharynx (Phy), which is differentiated from the succeeding oesophagus (Oe) by being somewhat broader and by its location anterior to the nerve connectives. The oesophagus is distended posteriorly to form a crop (0). The crop is clothed internally with bristles, which are not arranged in rows but scattered over the whole surface ( fig. 4), and which are all directed towards the centre of the crop. The presence of similar bristles has been noted by Aslam (1961) in several members of the Curculionidae. The crop leads directly into the gizzard, which is the widest part of the fore gut and posteriorly extends into the anterior portion of the mesenteron. The gizzard is further differentiated from the preceding crop by having sclerotised rods internally.The mid-gut is the widest portion of the alimentary canal and its anterior end surrounds the cardiac or stomodeal valve (SVfv). The whole of the mesenteron is of uniform diameter, and distributed over its entire external surface are numerous short papillae or crypts. The junction between the mesenteron and the hind gut is guarded by a cup-shaped pyloric valve (PVlv).The hind gut is a convoluted tube of variable diameter divisible into an anterior intestine, made up of an ileum and a colon, and a more posterior rectum. That region of the ileum containing the pyloric valve lies just anterior to, and above, the hind margin of the third visible sternite (the true fifth). From this point the ileum turns first downwards and then forwards so that it comes to lie beneath the mid-gut and to the left of the mid-line. The ileum runs anteriorly until it almost reaches the left hind coxal cavity, where it loops upwards and then, as the colon, runs posteriorly, widening gradually until it reaches the rectal valve (Rev). At this point the colon

The tracheal system in post‐embryonic development of holometabolous insects: a case study using the mealworm beetle

“…(Cerambycidae) a single mesoleg is penetrated by a branching trachea, while in T. molitor the meso‐ and metalegs are aerated by two tracheae ( mplt , malt ) that connect to form a common leg trachea ( clt ) before entering the leg. The latter image was also observed by Hafeez & Gardiner () in a relatively close relative of T. molitor , Tribolium anaphe . Material analysed suggests that at the time of metamorphosis, the differentiation of mplt and malt occurs in the meso‐ and metalegs (Figs C and B).…”

“…These tracheae originate from dlt along the entire length of prothorax. Additionally, the three largest branches which aerate these muscles arise directly from the latero-posterior wall of the first tracheal vestibule (ttv 1 ) - (Tonapi, 1977), dorsal cervical (Whitten, 1968) dlt Dorsal longitudinal trunk Whitten (1968) Alternative terms: lateral longitudinal trachea (Loudon, 1989), dorsal lateral trunk/lateral trunk (Hafeez & Gardiner, 1964), large lateral longitudinal trunks (Tonapi, 1977), dorsal longitudinal trachea (Chapman, 1918), lateral plurisegmental tracheal trunk (Snodgrass, 1935)…”

“…Specifically, a particular tracheal vestibule gives rise to the anterior (malt) and posterior part of the main leg trachea (mplt), which then connects, forming the main leg trachea (mlt) (Figs 2C and 6B). In larval forms, Hafeez & Gardiner (1964) and Tonapi, (1977) Alternative term: ventral tracheal anastomosis/ventral ganglionic (Whitten, 1968), ventral tracheal commisure (Snodgrass, 1935) vhc…”

“…Ventral head commissure Hafeez & Gardiner (1964) vht Ventral head trachea Alternative terms: ventral cephalic trachea (Tonapi, 1977), ventral cervical (Whitten, 1968) vlt Ventral longitudinal trunk Alternative terms: ventral lateral trunk (Hafeez & Gardiner, 1964), lateral longitudinal trunk (Whitten, 1968), ventral longitudinal trachea (Chapman, 1918), ventral plurisegmental tracheal trunk (Snodgrass, 1935) (Snodgrass, 1935;Hafeez & Gardiner, 1964;Loudon, 1989) wt…”

“…Earlier works addressing this issue were based on dissections and illustrated with handmade drawings (e.g. Packard, 1898;Whitten, 1957;Hafeez & Gardiner, 1964;Tonapi, 1977), and are therefore prone to artefacts. For instance, Crowson (1981) states that beetle larval instars are equipped with a single primary order thoracic trachea on each side, as in the abdomen, which is not consistent with the most recent findings (Iwan et al 2015).…”