Skip to main content
Figure 4 | Frontiers in Zoology

Figure 4

From: Comparative larval myogenesis and adult myoanatomy of the rhynchonelliform (articulate) brachiopods Argyrotheca cordata, A. cistellula, and Terebratalia transversa

Figure 4

Myogenesis in Argyrotheca cistellula. Overlay of CLSM maximum projection micrograph and light micrograph, anterior faces upward. Scale bars equal 50 μm. Note that only two lobes are visible: the apical lobe (AL) and the mantle lobe (ML), which encloses the pedicle lobe. (A) Early larva in dorsal view with the dorsal mantle muscles (empty arrowheads), the early lateral mantle muscles (lmm), and early rudiments of the serial mantle muscles (double arrowheads). (B) Dorsal view of a later larval stage with the lateral mantle muscle strand (lmm), rudiments of the posterior muscle ring (arrow), dorsal mantle muscles (empty arrowheads), and the serial mantle muscles (double arrowhead). (C) Later larva in ventro-lateral left view with pedicle muscles (pm) that are connected to the ventral mantle muscles (empty arrows). The serial mantle muscles (double arrowhead) are connected to the lateral mantle muscles (lmm), the apical longitudinal muscles (alm) start to develop, and the early posterior muscle ring is visible (arrow). (D) Same stage as in C, dorsal view. The pedicle muscles (pm) are prominent and connect to the dorsal mantle muscles (empty arrowheads). In addition, the lateral mantle muscles (lmm), the serial mantle muscles (double arrowheads), a part of the posterior muscle ring (arrow), and the apical longitudinal muscles (alm) are visible. (E) Fully developed larva, ventral view. The apical transversal (atm) and the apical longitudinal muscles (alm) are fully developed and connect to the pedicle muscles (pm). The connection between pedicle muscles and dorsal mantle muscles (empty arrowheads) is visible in the anterior region of the pedicle muscles. Further indicated are the ventral mantle muscles (empty arrows), the serial mantle muscles (double arrowheads), the lateral mantle muscles (lmm), and the area of the posterior muscle ring (arrow). (F) Same larval stage as in E, ventro-lateral left view. The pedicle muscles (pm) are the most prominent muscles in the centre of the mantle lobe. They are connected to the apical longitudinal muscles (alm), which terminate at the apical transversal muscle (atm), which in turn forms a muscle ring in the apical lobe. The ventral mantle muscles (empty arrows) and dorsal mantle muscles (empty arrowhead) are also connected to the pedicle muscles. The serial mantle muscles (double arrowhead) extend dorsally and ventrally from the lateral mantle muscles (lmm). The latter terminate at the posterior muscle ring (arrow).

Back to article page