A "'tegmen "'( plural : " tegmina " ) designates the modified leathery front wing on an insect particularly in the crickets and similar families ), Mantodea ( praying mantis ), Phasmatodea ( stick and leaf insects ) and Blattodea ( cockroaches ).
22.
The authors stated that " a high degree of conflict exists between the molecular and morphological data, possibly indicating that much homoplasy is present in Ensifera, particularly in acoustic structures . " They considered that tegmen stridulation and tibial tympanae are ancestral to Ensifera and have been lost on multiple occasions, especially within the Gryllidae.
23.
The tympanic antrum is bounded above by a thin plate of bone, the tegmen tympani, which separates it from the middle fossa of the base of the skull; below by the mastoid process; laterally by the squama just below the temporal line, and medially by the lateral semicircular canal of the internal ear which projects into its cavity.
24.
The term " tegmen " refers to a miscellaneous and arbitrary group of organs in various orders of insects; they certainly are homologous in the sense that they all are derived from insect forewings, but in other senses they are analogous; for example, the evolutionary development of the short elytra of the Dermaptera shared none of the history of the development of tegmina in the Orthoptera, say.
25.
Adults are moderate-sized laemophloeids ( ~ 2 mm ) characterized by their prolonged heads, open procoxal cavities, an acuminate intercoxal process on the first visible abdominal ventrite, antennal club of six antennomeres, and male genitalia lacking a dorsal piece of the tegmen . " Metaxyphloeus " adults are dark brown or black, shining, with or without dorsal pubescence, and with one or two pairs of pale elytral maculae.
