English: Meioglossus psammophilus light- and scanning electron micrographs (LM and SEM). A. Overview of specimen, lateral view, LM (bright field, DIC). B. Cross section of anterior trunk region showing dorsal position of sperm, LM (bright field). C. Dorsal live view, paratomy (transverse fission, two individuals) and sperm, LM (bright field). D. Semithin sagittal section, toluidine blue stained, LM. E. Specimen showing paratomy, lateral view, SEM (ZMUC-ENP-6). F. Close up from E of anterior end, dorsal view, SEM. G. Specimen showing paratomy, dorsal live view, LM (dark field). H. Different shapes and sizes of sperm heads from paratomy specimen in G, LM (phase contrast). I. Sperm heads and flagella, LM (bright field, DIC). J. Close up of sperm heads from I. Abbreviations: an, anus; cb1, cb2, 1. & 2. ciliary band; co, collar region; en, endodermal cell; ep, epidermis; es, esophagus; gl, glomerulus; gp, gill pore; hg, hindgut; lm, longitudinal muscles; mc, mesocoel; mec, metacoel; mg, midgut; MHC, midgut-hindgut constriction; mo, mouth opening; nt, nerve tissue; pb, proboscis; pbgl, proboscis gland; pc, protocoel; ph, pharynx; phf, pharyngeal fold; phm, perihaemal muscles; plm, proboscis longitudinal muscles; sf, sperm flagellum; sh, sperm head; sp, sperm; TF, transverse fission zone; tr, trunk; tg, tail glands.