{"id":408,"date":"2015-11-25T18:09:02","date_gmt":"2015-11-25T18:09:02","guid":{"rendered":"https:\/\/blogs-staging.imperial.ac.uk\/studentblogs\/victoria14\/?p=408"},"modified":"2015-11-25T18:09:02","modified_gmt":"2015-11-25T18:09:02","slug":"what-worm-is-that","status":"publish","type":"post","link":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/2015\/11\/25\/what-worm-is-that\/","title":{"rendered":"What worm is that?"},"content":{"rendered":"

I started species identification of earthworms after attending a course in 2013 which proved very useful when I went on to sample earthworms and other soil animals during my MSc project.\u00a0After my masters I continued identifying earthworms as a volunteer for the Natural History Museum Soil Biodiversity Group<\/a> as well as for ‘fun’ collecting species records for the Earthworm Society of Britain which I continue to do in addition to identifying samples for my PhD project.\u00a0For such an ecological important group earthworms are terribly under-recorded but with\u00a0just a small number of species, good identification keys and reasonably clear identification features they are a nice group to ‘do’. There is lots of advice on earthworm sampling and recording on the\u00a0Earthworm Society of Britain\u00a0website<\/a>\u00a0and they also run identification courses.<\/p>\n

So how do you identify an earthworm?<\/p>\n

Firstly in most cases your earthworm needs to be an adult, mature earthworms have a saddle (clitellum) which is part of the reproductive system \u2013 forming a cocoon which protects the earthworm\u2019s eggs.<\/p>\n

\"Adult<\/a>
Adult earthworm showing saddle<\/figcaption><\/figure>\n

There are 27 species of earthworm in the UK, but only a few\u00a0can be reliably identified in the field, for these you can use the free OPAL Earthworm Guide<\/a> or online key<\/a> but\u00a0most\u00a0require close examination using a microscope and an identification key. For\u00a0UK earthworm identification there is\u00a0Sherlock (2012)<\/a>,\u00a0published by the Field Studies Council<\/a>\u00a0and part of their excellent AIDGAP (Aid to Identification in Difficult Groups of Animals and Plants) series and the not so user-friendly\u00a0Sims and Gerard (1999)<\/a>. Both of these keys are dichotomous – each question (or couplet) in the key has (generally) two paths to follow. The trouble with dichotomous keys is that you can get stuck if the specimen is missing the feature in question (e.g. headless!) or if you make an error\u00a0and\u00a0end up on the path to the wrong species. An alternative type of key is\u00a0multi-access or ‘synoptic’ key, where the user selects the characteristics presented in the specimen and is presented with a list of species which fit the characters. A multi-access key to earthworms<\/a> has been developed by Rich Burkmar of the\u00a0Field Studies Council based on the AIDGAP key.<\/p>\n

\"Earthworm<\/a>
Earthworm underside showing some features used in earthworm identification<\/figcaption><\/figure>\n
\n
\"Top
Top view of earthworm head and clitellum<\/figcaption><\/figure>\n

In the FSC key Lumbricus<\/em> and one other genus are separated in the first couplet by the structure of their head. At the head of the worm is a fleshly lobe or prostomium which covers the mouth, in some earthworms two lines run from the prostomium so from the top it looks like the first segment is split into three, this is known as a tanylobic head and is the type found in Lumbricus<\/em> (the other type is called epilobic). Earthworm identification often requires counting the\u00a0number of segments before the clitellum and how many segments the clitellum covers which can be quite tricky if the segments are indistinct, or if you are distracted while counting!<\/p>\n<\/div>\n

\n
\"Aporrectodea<\/a>
Aporrectodea caliginosa showing epilobic type head<\/figcaption><\/figure>\n<\/div>\n
\n

Other characters used in earthworm identification are the position and shape of the tubercula pubertatis (TP for short) which are a pair of raised pads on the side of the clitellum. Some earthworms have very distinctive TPs.\u00a0\u00a0One of the most common UK earthworms is\u00a0Aporrectodea caliginosa,<\/em>\u00a0which generally has two bumps on segments 31 and 33, which can\u00a0sometimes be seen without a microscope.<\/p>\n<\/div>\n

\n
\"The<\/a>
The distinctive two bumps forming the TP of Aporrectodea caliginosa<\/figcaption><\/figure>\n<\/div>\n
\n

Another earthworm with a distinctive TP is\u00a0Satchellius mammalis<\/em> with a\u00a0crescent shaped TP. This small red earthworm is found in woodland and dead wood, and was the 5th commonest species I found in my MSc study site.<\/p>\n<\/div>\n

\n
\"The<\/a>
The crescent-shaped bump on the TP of Satchellius mammalis<\/figcaption><\/figure>\n<\/div>\n
\n

In the two years I have been studying earthworms I have found and identified 19 out of the 27 species in the UK, 14 of which can be found just in my garden! I hope eventually to meet them all, but\u00a0a couple of species are very rare and another has only been found in Eire, so this may be difficult!<\/p>\n

Earthworms I have found and recorded:<\/p>\n

Allolobophora chlorotica<\/em>
\nAllolobophoridella eiseni<\/em>
\nAporrectodea caliginosa<\/em>
\nAporrectodea icterica<\/em>
\nAporrectodea limicola<\/em>
\nAporrectodea longa<\/em>
\nAporrectodea rosea<\/em>
\nDendrobaena attemsi<\/em>
\nDendrodrilus rubidus<\/em>
\nEisenia fetida<\/em>
\nEiseniella tetraedra<\/em>
\nLumbricus castaneus<\/em>
\nLumbricus festivus<\/em>
\nLumbricus rubellus<\/em>
\nLumbricus terrestris<\/em>
\nMurchieona muldali<\/em>
\nOctolasion cyaneum<\/em>
\nOctolasion lacteum<\/em>
\nSatchellius mammalis<\/em><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

I started species identification of earthworms after attending a course in 2013 which proved very useful when I went on to sample earthworms and other soil animals during my MSc project.\u00a0<\/p>\n","protected":false},"author":1033,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[94586,95495,1],"tags":[],"class_list":["post-408","post","type-post","status-publish","format-standard","hentry","category-earthworms","category-identification","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/posts\/408","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/users\/1033"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/comments?post=408"}],"version-history":[{"count":0,"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/posts\/408\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/media?parent=408"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/categories?post=408"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs-staging.imperial.ac.uk\/student-blogs\/wp-json\/wp\/v2\/tags?post=408"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}