Protozoa Guide review

Oxymonas Janicki

genus / OXYMONADIDA / OXYMONADIDAE

Description

Club-shaped cell (5-165 ~m) with an anterior extensile rostellum containing fibers which arise at the base of the attachment point (Fig. 11 ). In attached forms a terminal nodule like a holdfast insures the fixation to the intestinal intima. The 4 flagella arise in 2 pairs in the shoulder region. The crystalline axostyle originates at the base of the rostellum , traverses the cell, and protrudes at the posterior end where it is surrounded by a sheath . The nucleus is generally anterior, at the base of the rostellum. Electron microscopic study has shown the oxymonad characters : presence of a preaxostylar lamina connected to the 2 pairs of basal bodies and a crystalline axostyle composed of parallel rows of microtubules (Fig . 4c). The rostellum is composed of a central bundle of non- organized microtubules surrounded by circonvoluted microtubulear ribbons arising at tne base of the holdfast and penetrating into the cell body (Fig . 4d) . The rostellum is terminated by a holdfast containing microfibrils (Fig . 4e). Attached flagellates are non-motile , and unattached ones swim in the intestinal fluid and partly loose their rostellum . Twenty-two species living in Kalotermitidae (Kofoid and Swezy, 1926 ; Connell, 1930; Zeliff , 1930; Cross, 1946) and 2 in the roach Cryptocercus (Cleveland, 1 95 Oc). Hormone-induced sexual cycle compns1ng gametogenesis, fertilization, and meiosis has been described in species living in the roach Cryptocercus (Cleveland, 1950c). Ultrastructure study in Brugerolle and Konig, 1997; Rother et al., 1999) .

Type species

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Raw text

Club-shaped cell (5-165 ~m) with an anterior
extensile rostellum containing fibers which arise at
the base of the attachment point (Fig. 11 ). In
attached forms a terminal nodule like a holdfast
insures the fixation to the intestinal intima. The 4
flagella arise in 2 pairs in the shoulder region. The
crystalline axostyle originates at the base of the
rostellum , traverses the cell, and protrudes at the
posterior end where it is surrounded by a sheath .
The nucleus is generally anterior, at the base of the
rostellum. Electron microscopic study has shown
the oxymonad characters : presence of a
preaxostylar lamina connected to the 2 pairs of
basal bodies and a crystalline axostyle composed of
parallel rows of microtubules (Fig . 4c). The
rostellum is composed of a central bundle of non-
organized microtubules surrounded by
circonvoluted microtubulear ribbons arising at tne
base of the holdfast and penetrating into the cell
body (Fig . 4d) . The rostellum is terminated by a
holdfast containing microfibrils (Fig . 4e). Attached
flagellates are non-motile , and unattached ones
swim in the intestinal fluid and partly loose their
rostellum . Twenty-two species living in
Kalotermitidae (Kofoid and Swezy, 1926 ; Connell,
1930; Zeliff , 1930; Cross, 1946) and 2 in the
roach Cryptocercus (Cleveland, 1 95 Oc).
Hormone-induced sexual cycle compns1ng
gametogenesis, fertilization, and meiosis has been
described in species living in the roach
Cryptocercus (Cleveland, 1950c). Ultrastructure
study in Brugerolle and Konig, 1997; Rother et al.,
1999) .