Ref ID : 3070
Sudzuki Minoru; [On the General Structure and the Seasonal Occurrence of the Male in Some Japanese Rotifers VII]. Zoological Magazine (Dobutsugaku Zasshi) 67(11):348-354, 1958
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20) Trichocerca (Diurella) similis (Wierzeiski) = ?T. birostris (Minkiewicz): The specimens from Urawa (M1) may be regarded as a mono- or oft. di-cyclic autumn form (maximum, Nov. to Dec.), as the D-Female females are usually found from the end of September (very rarely in the middle of June) to December; during 1953-55 the Female-Female females appeared only slightly later than birostris of Sweden; in 1956, however, they were found in all seasons displaying maxima in the middle of May, the end of June and the middle of September. The males are 68-73 µm in total length, 60-70 µm in body length, 45 µm in width and 37-39 µm in height. The foot 5x7 µm in size. No chitinous plate but with a ciliary wreath. One dorsal feeler with a seta. Testis 22-30x20-22 µm in size. 21) Trichcocerca sp. 1 (capucina?): Only an adult male was collected from M1 on Sept. 13,'55. Total length 58 µm, body length 43-55 µm, width 26-29 µm. Cephalic ganglion 24x13 µm. Prostate glands 5 µm. Bladder 5x3 µm. Testis 18x7 µm. Ductus seminalis 12x3 µm. Penis 7 µm in length 5 µm in diameter with a 2.5 µm long ciliary wreath. Gonopore 1 µm in diameter. Foot, motile, 6x4 µm in size. 22) Trichocerca sp. 2: An adult was found from M1 on Nov. 4,'54. This male is much like that of T. pusilla in form. This is surely a male hitherto undescribed (judging from all the females then encountered at the same place). Body length 65-72 µm, height 28-30 µm. Foot 4x3 µm. 23) Trichocerca sp. 3: From M1 on July 7,'55. Body 77 µm long, 35 µm wide. 24) Trichocerca sp.4: A male in embryonal stage was collected from M1 on Sept. 21,'54. Judging from all the female then occurring in the same habitat, the male seems to be new. All Trichcocerca males from Japan are much different from those from Denmark (W-L) in the following main characters: 1) they are clearly provided with a motil foot, never 'No Foot'. 2) Penis with a ciliary wreath, not a 'Chitinous Plate' and 3) Dorsal feeler with a long sensory seta, instead of 'Soft Hairs'. The male of the old genus Diurella is closely allied to that of Trichocerca. Consequently, we should not separate, on the generic level at least, Diurella from Trichocerca. On the other hand, according to the present author's opinion, the males of T. pediculus and T. pygocerca are markedly different in general form from that of common Trichocerca species. Thus, we could divide the genus Trichocerca into three groups as follows: 1) Group I, which comprises the majority of Trichocerca species including also Diurella species. 2) Group II with T. cylindrica etc. and 3) Group III which comprises such Psammon spp. as T. pediculus, T. pygocerca (cf. Ruttner-Kolisko '56, S.394). 25) Collotheca ornata ornata (Ehrb.): Summer form. Body 53-58 µm long, 17-20 µm wide. Pretty long trochal cilia, 10 µm in length. Cephalic ganglion 10-12x7-8 µm. Two red apical eyes with a lens on the conical disc. One dorsal feeler. Flame bulbs 5-7 on each side. Vacuole-like structure 7x7 µm in size in the middle of the trunk. Testis 17x13-14 µm wide 5-6 atypical sperms. Seminal duct not curved, 10-18 µm in length, 3 µm in diameter. No true penis. Prostate glands 2x2 µm in size. The foot 8x5 µm with a vestigial peduncle provided with no cilial tuft. Pejler's male (Col. libera '57 p.11) is much different from those figured by Wesenberg-Lund and the present author, it rather reminds us of that of Brachionidae (e.g. Kellicottia?).