COMPARATIVE-MORPHOLOGICAL ANALYSIS OF THE ORGANIZATION OF CEPHALORHYNCH WORMS, T

2020-04-05 17:41:00

The characterized Fig cuticle loriciferans

责任者: ADRIANOV, AV;MALAKHOV, VV 单位: MOSCOW MV LOMONOSOV STATE UNIV,MOSCOW,RUSSIA. 来源出处: ZOOLOGICHESKY ZHURNAL, v 74, MAY 1995, p 3- 18 摘要: Priapulids are characterized by the most primitive cuticle within Cephalorhyncha (fig. 1). Their cuticle consists of ab outer homogeneous dense layer covered with thin osmiophilic trilaminate membrane, and an inner fibrillar layer. Because of the presence of the loricated armour, the homogeneous layer is sclerotized in the larvae of priapulids and loriciferans. Kinorhynchs are characterized by the most sclerotized cuticle within Cephalorhyncha. The specific undulating locomotion caused the appearance of the multifibrillar cuticle characterized by the layers of spiral fibers in nematomorphs. Priapulids have continuous dermomuscular tube (fig. 2). In loriciferans, the dermomuscular tube is discontinuous being composed of separated muscular bundles. In the trunk region of nanoloricids, circular muscles are reduced being replaced by diagonal and dorsoventral ones (fig. 3). Kinorhynchs are characterized by well - differentiated metamerized musculature formed by separated longitudinal, diagonal and specialized dorso - ventral muscles (fig. 4). Because of the undulating locomotion, nematomorphs retain only longitudinal muscles. All cephalorhynchs have intraepithelial nervous system. The unity of all cephalorhynchs is well confirmed by common structural pattern of the central nervous system consisting of circumpharyngeal nerve ring (circular brain) and ventral nerve cord (fig. 6). Ganglionization of the nerve ring is described in priapulids, loriciferans and kinorhynchs. The ventral cord of loriciferans and larvae of priapulids has a neck- and some trunk ganglia. The ventral cord of kinorhynchs is metamerously ganglionized. The anterior part of nervous systemin priapulids is presented on the figs. 7 and 8. The same of kinorhynchs - on the fig. 9. 关键词: COALESCENCE; DIRECT LASER VAPORIZATION; FULLERENE; MASS DISTRIBUTION; TOF MASS SPECTROMETRY TOF MASS SPECTROMETRY; HALICRYPTUS-SPINULOSUS; PRIAPULUS-CAUDATUS; FINE-STRUCTURE; CUTICLE