KEY TO IMPORTANT ADULT HUMAN CESTODES
1.
Scolex "head" recovered................................................................................. 2
Gravid proglottids recovered........................................................................... 5
Complete worm (scolex & 3 proglottids:
immature, mature, and gravid).....................................
Echinococcus species
2.
Large scolex (about 1-2 mm).......................................................................... 3
Small scolex (0.3 to 0.5 mm)........................................................................... 4
3.
Scolex with two longitudinal, slit-like grooves
or suckers...................................................................... Diphyllobothrium latum
Scolex with four round suckers, unarmed................ Taeniarhynchus saginatus
Scolex with four round suckers, armed........................................ Taenia solium
4.
Scolex club-shaped about 0.5 mm, unarmed................. Hymenolepis diminuta
Scolex armed with one row of large hooks,
about 0.3 mm in diameter .................................................... Hymenolepis nana
Scolex armed with 3-7 rows of small hooks,
0.25 to 0.5 mm in diameter................................................. Dipylidium caninum
5.
Segments broader than long........................................................................... 6
Segments longer than broad........................................................................... 8
6.
Single ventral genital pore, rosette uterus..................... Diphyllobothrium latum
Single lateral genital pore, uterus: transverse elongated sac.........................
7
7.
Segments less than 1 mm in breadth................................... Hymenolepis nana
Segments about 2.5 mm in breadth............................... Hymenolepis diminuta
8.
Uterus composed of a large number of egg's packets,
bilateral genital pores.......................................................... Dipylidium caninum
Uterus with a median stem and lateral branches, single genital pore............. 9
9.
Uterus with 7 to 13 lateral uterine branches per side.................. Taenia solium
Uterus, with 15-30 lateral uterine branches per side..Taeniarhynchus saginatus
Table 3-2. Key to important adult human cestodes.
MD0842
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