Spiny Headed Worms

Life cycle of acanthocephalans Moniliformis moniliformis and Macracanthorhynchus hirudinaceus Eggs are shed in the feces of the definitive hosts (1), which are usually rats in the case of M. moniliformis and swine for M. hirudinaceous, although carnivores and primates, including humans, may serve as accidental hosts. The eggs contain a fully-developed acanthor when shed in feces. The eggs are ingested by an insect intermediate host (2) (usually scarabaeoid or hydrophilid beetles for M. hirudinaceus and beetles or cockroaches for M. moniliformis). Within the hemocoelom of the insect, the acanthor (2a) molts into a second larval stage, called an acanthella (2b). After 6-12 weeks, the worm reaches the infective stage called a cystacanth (2c). The definitive host becomes infected upon ingestion of intermediate hosts containing infective cystacanths (3). In the definitive host, liberated juveniles attach to the wall of the small intestine, where they mature (4) and mate in about 8-12 weeks. In humans (5), the worms seldom mature, or mature but will rarely produce eggs.From Centers for Disease Control Parasites and Health website

USNM 1356514, USNPC 060771 - 60771 C kuntzi Holo 20x

USNM 1356515, USNPC 060772 - 60772 C kuntzi Para2 40x

USNM 1356514, USNPC 060771 - 60771 C kuntzi Holo2 20x

USNM 1356515, USNPC 060772 - 60772 C kuntzi Para 40x

USNM 1319910, USNPC 006772 - 6772 M grandis F voucher tail eggs 10x

USNM 1320666, USNPC 007911 - 7911 M grandis male deeper foc Type 10x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type cg 10x

USNM 1319910, USNPC 006772 - 6772 M grandis female voucher 20x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type ant testis 5x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type lem3a hi foc 10x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type lem2 10x

USNM 1319910, USNPC 006772 - 6772 M grandis F voucher lem2 5x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type near end tail 10x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type cgland 5x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type lem3a deep foc 10x

USNM 1319910, USNPC 006772 - 6772 M grandis F voucher lem3 5x

USNM 1320666, USNPC 007911 - 7911 M grandis male deep foc Type 10x

USNM 1319910, USNPC 006772 - 6772 M grandis F voucher lem1 5x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type 10x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type lem4 10x

USNM 1319910, USNPC 006772 - 6772 M grandis F voucher lem4 5x

USNM 1319910, USNPC 006772 - 6772 M grandis F voucher width 5x

USNM 1320666, USNPC 007911 - 7911 M grandis male Type tail 5x