TY  - JOUR
JF  - Acarologia
T1  - Spermatogenesis and sperm structure in astigmatic mites Glycyphagus domesticus (De Geer) and Diplaegidia columbae (Buchholz), with some comments on the actual structure of the testis (Acariformes: Astigmata)
VL  - 66
IS  - 4
SP  - 868
EP  - 889
PY  - 2026
SN  - 0044-586X
SN  - 2107-7207
PB  - Les Amis d'Acarologia
AU  - Witaliński, Wojciech
AU  - Podkowa, Dagmara
UR  - https://doi.org/10.24349/2xva-xiwf
DO  - 10.24349/2xva-xiwf
DA  - 2026-10-01
ET  - 2026-10-01
KW  - pleomorphic spermatozoa
KW  - chromatin
KW  - testis
KW  - astigmatic mites
KW  - Glycyphagoidea
KW  - Analgoidea
AB  - The male reproductive systems, spermatogenesis and spermatozoa of two mite species belonging to Astigmata, Glycyphagus domesticus (Glycyphagoidea: Glycyphagidae) and Diplaegidia columbae (Analgoidea: Analgidae) are described. In G. domesticus, the male reproductive system comprises the paired testes, however the left one is shorter and is replaced anteriorly with a male accessory gland. Each testis contains the dorsally located germarium with spermatogonia, whereas the spermatocytes and spermatids are spread ventrally. In the lower part of each testis, the beginning of a deferent duct, filled with spermatozoa, is located. Both deferent ducts and the duct of an accessory gland join into the ejaculatory duct, which is S-shaped in the axial plane and enters the aedeagus to finally terminate at its tip. On the surface of spermatocytes a spongy layer appears, formed by the anastomosing membranes of Golgi origin. At the end of spermatocytogenesis, spherical nucleus containing nucleolus disappears. Spermatocytes in meiotic division have not been observed. Spermatids are singular, roundish cells with electron-lucent cytoplasm containing several profiles of electron-dense lamellae, mitochondria and conspicuous spongy body formed by anastomosing membranes, representing the so-called OSER (Organized Smooth Endoplasmic Reticulum). The spongy body comprises a peripheral layer, with sinusoidal, anastomosing, double membranes, along with more central, large core containing a very regular pattern of membranes. Spermatozoa are the pleomorphic cells, with granular chromatin assembled sub-centrally and surrounded with several electron-dense lamellae, as well as numerous mitochondria. In D. columbae, the male reproductive system contains unpaired testis filled with germ cells (advanced spermatogonia, primary spermatocytes and groups of secondary spermatocytes and spermatids), short and thick unpaired deferent duct, which passes into the ejaculatory duct, the latter emptying at the aedeagus tip. Spermatozoa are assembled in a ventral part of the testis where the entrance to the deferent duct is formed. Germarium in the testis was not observed. No male accessory gland was found, either. As in the G. domesticus, in D. columbae a spongy layer appears at the surface of primary spermatocytes, which persists up to the spermatid stage. Chromatin in spermatids appears as fine threads embedded in the cytoplasm. Subsequently, chromatin condenses into granules. Spermatozoa in D. columbae are pleomorphic cells, with granular chromatin assembled sub-centrally and surrounded with the stacks of several electron-dense lamellae; scarce mitochondria may also be encountered. Spermatids exhibiting degenerative symptoms may also be observed.
ER -