"Microchaetus Rappi" It’s largest earthworm, average length is about 1.36 m, but can be 6.7 m long

Microchaetus rappi, the African giant earthworm, is a large earthworm in the Microchaetidae family, the largest of the segmented worms (commonly called earthworms).

It averages about 1.4 m (4.5 ft) in length, but can reach a length of as much as 6.7 m (22 ft) and can weigh over 1.5 kg (3.3 lb).

Microchaetus rappi was first described in 1849 by Dr. Rapp as Lumbricus microchaetus with “an associated proposal for a new genus named Microchaetus”.

Microchaetus was also presented as a possible new genus at the time. The site in where it was originally documented was labelled as ‘Cape’, a southern region in South Africa.

They were described to surface after heavyrain, were almost 4 feet long, 6 feet when stretched out, and were “about as thick as one’s forefinger”.

In a letter from Rapp to his colleague Beddard, it was stated that “these worms appear only one, two, or three times a year.

They never seem to return to the earth, but to be killed within six hours by the heat of the sun”.

The letter goes on to state that “no domesticanimal whatever dogs, pigs, fowls &c. touch them.”.

The soil they were found in was described as “impregnated with brackish water”.

Plisko states in her article that the broad description of the site “was imprecise”, and when originally described by Rapp, “the recorded observations on the anatomy were very few”.

In the same paper, Beddard requested and received specimens of large earthworms for careful dissection and study.

After dissection, he decided that the species of worm should be Microchaeta rappi rather than L. microchaetus.

According to Plisko, taxonomic problems in regards to M. rappi have been present for decades.

Originally classified as Lumbricus microchaetus by Rapp, it was proposed by Beddard in 1886 that the name should be changed to Microchaetus rappi and “the specimen previously described by Rapp should also be recorded under this new name”.

In 1886, Benham accepted the change in taxonomy “as valid for the species described by Rapp, and relegated the original name microchaetus to the synonymy of rappi”.

The genus Microchaetidae is classified and grouped through a key that details anatomic features of each genii.

Organisms classified as Microchaetus rappi have “excretory system holonephric; nephropores present; only one gizzard present,

in segment 7 testes and male funnles in other than proandric arrangement testes and male pores in holandric arrangement; nephiridial bladders V-shaped … spermathecae always prosterior to testis locations”