The tergal and pleural wing base sclerites – homologous within the basal branches of Pterygota?

Figures & data

Figure 1. Homology of the axillary sclerites of Ephemeroptera and Neoptera (modified after Willkommen 2008). (a) Habroleptoides confusa (Ephemeroptera), right forewing. (b) Perlodes microcephalus (Plecoptera), right hind wing.

Figure 2a–f. Direct flight muscles of the mesothorax of Ephemeroptera (Siphlonurus aestivalis). Muscle homology after Willkommen 2008 (modified after Willkommen 2008).

Figure 3a–e. Direct flight muscles of the synthorax of Odonata (Sympetrum cf. striolatum). Muscle homology after Willkommen 2008 (modified after Willkommen 2008).

Figure 4a–c. Direct flight muscles of the mesothorax of Plecoptera (Brachyptera seticornis). (modified after Willkommen 2008).

Table 1. Different hypotheses on the presence (+), absence (−), or different interpretation (1Ax) of basalar muscles in Ephemeroptera. For explanations of “*” and “**” see text.

	Knox 1935	Matsuda 1956	Matsuda 1970	Tsui and Peters 1972	Brodsky 1974	Kluge 1994
BA.SmS (p-s12)	+	+	+	+	+	+
BA.SmI (p-s 12)I	+	+	+	+	+	+
BA.Pm (p 5)	+	+	+	+	+	+
BA.Cm (t-cx 4)	+	— (1Ax)	— (1Ax/2Ax*)	— (1Ax)	+	+
BA.Trm (p-tr 2)	+	—	— (basalare/1Ax**)	—	?	+

Figure 5. Mesopleuron of a male imago of Siphlonurus aestivalis. BA – basalare of Ephemeroptera sensu Kluge 2004 (grey areas sclerotised; modified after Willkommen 2008).

Figure 6. Mesopleuron and metapleuron of a late larva of Baetis sp., the arrows show the attachments of the basalar and subalar muscles. SA.Cm – subalar-coxal muscle of Ephemeroptera (terminology sensu Kluge 2004); fwp – forewing pad; hwp – hind wing pad. Scale: 1 mm (modified after Willkommen 2008).

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