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CONOCHILIDAE, (REMANE, 1933) (family)

       Jaws malleoramate. Fulcrum short, rami
more or less triangular, flat; unci teeth
numerous. Planktonic and
epiphytic on roots of
(Water hyacinth),
Arora and Mehra, 2003c).


Foot fairly stout, without toes. Lorica absent,
i.e. cuticle thin and flexible, not usually
retaining its shape well after preservation.
A gelatinous, transparent case around foot
and part of the body Head not funnel-like.
Solitary (Conochiloides) or in colonies
(Conochilus). Conochilus disappeared from
Laguna de Bay in periods with relatively
high salinity, thus showing sensitivity to
the increased salinity.
specimens separated from gelatinous case.
Formalin-sugar-preserved specimens still
in gelatinous case, usually strongly contracted.
Antenna present, planktonic.
The genus
, EHREN­BERG 1834, and Conochiloides,
HLAVA 1904, can be separated based on the degree
of fusion of the antennae. However,
intermediates between total fused and unfused
antennae are found and the two genera will be
treated as one (
Conochilus) with two separate
groups (Ruttner-Kolisko 1972).
Feeds on
particles less than
10 μm (Sládeček 1983).


74 a. Antenna more or less separated, 

74 b. Antenna fused completely or nearly so, 
CONOCHILUS GROUP....................................76

      Antenna more or less separated


75 a. Antennae largely fused proximally to about 
one-third the length and free and the distal end

situated below corona.
Basal mound is lacking. 
Mouth central.
Right uncus has five large teeth, 
the left uncus three.
Solitary in gelatinous 
case – not colonial. Body vase shaped. 
Size (without case, expanded) 250
Feeds on unicellular algae up to 18 μm 
and shows affinity to bluegreen-algae 
in Lake Lanao (Lewis 1979b). Planktonic 
in lakes and ponds, thermophilic.
- Laguna de Bay, Lake Mainit, Lake Lanao, Paoay Lake.
   Conochilus dossuarius, (HUDSON, 1885)
   (syn. Conochiloides dossuarius)
          [1941a, 1973, 1977, 1978a+b+d 1979b, 
           1980, 1984a, 1986a, 2003b, 2008b]

C. dossaurius from Laguna de Bay

C. dossaurius from Bunot Lake


75 b. Ventral antennae arise from a mound-like 
expansion of equal length as the antennae, 
which are separated in their total length. 
Ventral antenna prominent. The foot is short 
and almost entirely contracted when fixed. 
Each uncus has three large teethes; one of 
the teeth of the left uncus is divided into 
three branches, however. Total length 160
Body length 110-115
- IRRI Rice field, Lake Danao
   Conochilus coenobasis SKORIKOV, 1914.


Antenna fused completely or nearly so.


76 a. Antenna fused completely or nearly so, 
situated in the mouth field or the corona, 
mouth dorsal. In colonies of varying size 
(5-12 individuals), living together 
in a spherical gelatinous hull.
The colony
is less vulnerable to be attacked by
Asplanchna and probably by copepods, too.
Efficient consumer of bacteria-sized
particles and thus an important consumer
within the microbial loop
(Wallace et al. 2006).

Planktonic in oligotrophic lakes and ponds

(Sládeček (1983)
- Laguna de Bay, Sampaloc Lake.
   Conochilus unicornis, (ROUSSELET, 1892)
        [1980, 1984a]


C. unicornis from Laguna de Bay


C. unicornis fromSampaloc Lake 



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