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Barron, G.L.; Morikawa, C.; Saikawa, M. 1990: New Cephaliophora species capturing rotifers and tardigrades. Canadian Journal of Botany 68(3): 685-690.

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Barron, G.L.; Morikawa, C.; Saikawa, M. 1990: New Cephaliophora species capturing rotifers and tardigrades. Canadian Journal of Botany 68(3): 685-690.
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ADDITIONAL RECORDS: Recovered from moss scraped from a rock, Eramosa River bank, Guelph, Ontario, September 1988.
Hyphae of C. longispora are 6.2-7.5 µm wide, colourless, septate, and uniform in width (Figs. 16, 17). The hyphae are straight and sparingly branched, with most branches originating at right angles to the parent hyphae (Fig. 15). Adhesive pegs are 10.5-23.5 µm x 5.5-7.5 µm (Figs. 16, 17, and 21). Adhesive pegs tend to be broadest at or near the base and taper gradually to a rounded apex. They do not have the well-marked apical bulb of C. muscicola. In young cultures the pegs are more or less uniform in length, but as the hyphae age, a number of pegs continue growth and they lack the uniformity in size found in C. muscicola. Conidiogenous cells (Figs. 14, 20) are similar to those found in C. muscicola. Often, however, conidia are produced terminally on long branches (Fig. 21). These branches may be up to 200 µm long and have the appearance of conidiophores. This pattern of development takes place in water; thus a branch with a terminal cluster of conidia is not actually a support structure. If cultures are drained and conidia allowed to develop in air, conidiogenous cells are produced directly from prostrate hyphae, and elongate conidiophores are not produced. Conidia are very long, colourless, and multiseptate and have a marked curvature at the distal end (Figs. 14, 18, and 22). They range from 125-228 µm long and are 8.5-10 µm wide. In the presence of rotifers they develop from one to eight adhesive pegs directly from the cells (Figs. 18, 19, and 22). The species description is based on isolate No. 117.
In all the important aspects of its life cycle C. longispora is the same as C. muscicola. Cephaliophora longispora differs from C. muscicola in having much larger conidia (averaging more than 50 µm longer). Also, conidia of the latter have a strong curvature at the distal end, giving them a clawlike appearance in a cluster (Fig. 22). The adhesive pegs in C. longispora appear relatively short and squat and of a different shape. They are broader at or near the base and taper gradually to the apex. In C. muscicola the conidiogenous cells always arise directly from the hyphae, whereas in C. longispora the conidiogenous cell may be terminal on a more or less elongate lateral branch.
Tests showed that both species of Cephaliophora described above could capture and colonize tardigrades.
HABITAT: Capturing and consuming tardigrades and rotifers in moss.
Cellae (ampullae) conidiogenae plus minus sessiles, ellipsoideae, clavatae vel cylindricae, 6.2-7.2 µm latae usque ad 30 µm latae; conidia uno tempore nata, multiseptata, hyalina, navicularia, 125-228 µm longa x 8.5-10.0 µm lata; hyphae vegetae septatae, hyalinae, gerentes cellas tonaces; Celae tenaces 10.5-23.5 µm altae x 5.5-7.5 µm latae.
TYPE: Slides and pickled specimens in herbarium (OAC 10849). Isolated from mossy soil, collected in a kauri wood at Birkenhead, Auckland, December 25, 1988. Isolate No. 117.
ADDITIONAL RECORDS: From leaf mould collected on a riverbank, Agano River, Japan, April 18, 1986; mossy soil in a rainforest, Milford Sound, South Island, New Zealand, February 14, 1989; from moss, collected beside a woodland path, Geraldine, South Island, New Zealand, February 20, 1989.
Vegetative hyphae of C. muscicola are 4.0-6.8 µm wide, hyaline, septate and uniform in width. Hyphae are straight and sparingly branched, with secondary and tertiary branches arising at right angles to form a three-dimensional grid. Adhesive pegs are borne at intervals along the length of the hyphae (Figs. 6, 10). Four to six pegs are produced for every 100 µm of hyphae. Pegs arise mostly at right angles to the vegetative hyphae but may arise at an acute angle in some cases. Adhesive pegs (Figs. 7, 13) are slender, cylindrical, more or less uniform in width for most of their length, and 12.2-21.6 µm long by 3.5-5.4 µm wide. They are slightly broader at the base where they connect to the support hyphae and slightly indented below the rounded adhesive apex. Longer pegs are also found, but these are less regular in shape and appear to have been formed by renewed growth from the apex of a primary peg.
During feeding, rotifers seem attracted to the adhesive pegs and browse at their tips to which they may become attached (Figs. 4, 5). Infrequently, rotifers attach by the body. In most cases, however, attachment is in the mouth region and appears similar to the method of capture described for Zoophagus insidians (Sommerstorff 1911; Whisler and Travland 1974).
Penetration of the rotifer is accomplished by a renewal of growth from the tip of the adhesive peg, and broad, convoluted, nodular assimilative hyphae develop to colonize the body of the host (Figs. 11, 12).
After capture, rotifers struggle feebly but quickly encyst to a more or less spherical shape (Fig. 5). The body contents of the victim are colonized and digested until all that remains is a ball of assimilative hyphae inside the cuticle. Eventually the protoplasm in the assimilative hyphae is translocated elsewhere, and the shrivelled remains disintegrate and disappear by bacterial decay.
A succession of captures stimulates hyphal growth, and more adhesive pegs, with occasional clusters of conidia, are produced. Conidiogenous cells (ampullae) are cylindrical to clavate and often very similar to adhesive pegs (Fig. 6). With cylindrical conidiogenous cells the apex is slightly swollen. Conidia are produced synchronously, starting as buds from the ampulla and then elongating rapidly (Fig. 1). Mature conidia are long, narrow, multiseptate, hyaline, and cylindrical and taper gradually at both ends to a narrow, acutely rounded base and apex. They are slightly curved along their length to give a Fusarium-like appearance. Conidia (Figs. 2, 8, and 9) are 125-155 µm by 6.2-9.0 µm with 9-12 septa and are borne in clusters of three to six. Occasionally larger clusters (up to 30 conidia) are produced, especially when conidia develop inside the agar from subsurface hyphae. At maturity, conidia are readily dislodged from the ampulla and, after secession, drift off to settle on the substrate elsewhere. Conidia can be produced in water or air. If they are produced in air and rewetted, the spores float for extended periods supported by surface tension. In active cultures of rotifers, or if transferred to a fresh culture of rotifers, some conidia germinate to produce one or more adhesive pegs (Figs. 3, 10). As many as seven pegs have been found on a single conidium. Sometimes adhesive pegs develop on conidia while they are still attached to the ampulla; conidia in close proximity on an ampulla or on the substrate frequently anastomose. A conidium may also germinate from one or both ends to form short lengths of unbranched vegetative hyphae from which pegs are then produced (Fig. 5). Frequently a germinating hypha from one end grows straight down into the agar to anchor the conidium and eventually the colony that subsequently develops. With colonies anchored in this way, it is possible to wash Petri dishes fairly vigourously under running water to remove debris, bacterial sludge, and staling products found in old cultures. If fresh rotifers are added to washed colonies, then usually a large number of captures occur within an hour or two. No resistant spore state or sexual state has been found associated with this fungus. The species description is based on isolate No. 169.
In the Japanese isolate the adhesive pegs are more or less identical to those of the New Zealand isolates. The vegetative hyphae have a greater range in width (4.5-9.0 µm). As with isolate No. 169, the conidiogenous cells are short and 7-14 µm x 4.5 µm. The ampulla is up to 8 µm in width. In the Japanese isolate the conidia are similar in shape but larger, 150-200 µm x 7-11 µm and borne in clusters of two to four.
HABITAT: Capturing tardigrades and bdelloid rotifers in wet soil.
Cellae (ampullae) conidiogenae plus minus sessiles, clavatae vel cylindraceae cum apice tumidulo, 3.5-5.5 µm latae ad 27 µm longae; conidia uno tempore nata, multiseptata, hyalina, navicularia, 125-155 µm longa x 6.2-9.0 µm lata; hyphae vegetae, septatae, hyalinae, gerentes cellas tenaces; cellae tenaces, 12.2-21.6 µm altae x 3.5-5.4 µm latae.
TYPE: Slides and pickled specimens in herbarium (OAC 10848). Isolated from muddy soil collected in a ditch, Mt. Egmont Park, New Zealand, December 18, 1988. Isolate No. 169.

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1cb0ec6e-36b9-11d5-9548-00d0592d548c
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18 March 2001
26 September 2003
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