Click here hier to go to DUTCH version. Naar Nederlandse pagina to Dutch version


DOUBLE NAMING ANIMALS: examples from the ditch.

Naming the thrushes on the previous page wasn't all that difficult. On this page we proceed to name the creatures in the ditch and start with the genus Dytiscus or: Diving beetles. We take a look at four of the species. Dytiscus marginalis is the well-known Great diving beetle, and Dytiscus circumflexus will also often be given that same English name, because the only clear difference is that it has black spots on the under side. A somewhat smaller species is Dytiscus lapponicus which has yellow lines on the wingcases. A very rare species is Dytiscus latissimus which is broad en large. Here are the names and translations:

Great diving beetle  -  Dytiscus marginalis  -  Diver, margined     dytiscus marginalis
(No English name)  -  Dytiscus lapponicus  -  Diver, Lapponian
(No English name)  -  Dytiscus circumflexus  -  Diver, flexed round (?)
(No English name)  -  Dytiscus latissimus  -  Diver, broadest

Thus far things ain't to complicated. But that is due to the fact that these beetles are large and easy to distinguish. Most species of waterbeetle are (much) smaller and difficult to separate from each other, even harder without the aid of magnifying optics. So most of them don't have an English name. The different species all look much the same in appearance and habits, while different individuals of the same species may differ much in color for example. So the difficult task for the name givers of old was to solve the questions: which individuals are of the same species, to which genus does that species belong? Because the names are important in the systematics many waterbeetles had to be renamed based on facts found with later research. It might not surprise you that this happened a lot (in fact, it still happens a lot).
The fact that they lived in water caused many names to contain a "watery" part: Hydro- in connections as "Water loving" (Hydrophilus) or "Water cherishing" (Hydrocharis). It didn't make things more obvious. The Great diving beetle, which of course has been well-known through the ages, was named "Diver" (Dytiscus) in the old days, probably because of it's habit of diving from the surface to deeper water. Many other (little) waterbeetles behave like this, so they were all called something with Dytiscus. Furthermore there were many researchers who knew nothing of each others work (no internet in these days). So there existed different names for the same species, or sometimes the same name for different species. To give you an impression some older names are put below the official names in the table below. Notice that all the four beetles had a Dytiscus name.

Synonyms of waterbeetle names
Acilius sulcatus male

Acilius sulcatus female
Acilius sulcatus (Linnaeus, 1758)
Dytiscus sulcatus Linnaeus, 1758
Dytiscus punctatus Scopoli, 1763
Dytiscus fasciatus De Geer, 1774
Dytiscus scopolii Gmelin, 1790
Acilius caliginosus Curtis, 1825
Acilius scoticus Stephens, 1828
Acilius varipes Stephens, 1828
Acilius brevis Aube, 1837
Acilius laevisulcatus Motschulsky, 1845
Acilius tomentosus Motschulsky, 1845
Acilius blancki Peyerimhoff, 1927
   Noterus clavicornis (de Geer, 1774)
Dytiscus semipunctatus Fabricius, 1792
Dytiscus sparsus Marsham, 1802
Noterus convexiusculus Reiche & Sanky, 1855
  Noterus clavicornis
Hygrobia hermanni (Fabricius, 1775)
Dytiscus tardus Herbst, 1779
Paelobius Schönherr, 1808
  Hygrobia hermanni
Laccobius minutus (Linnaeus, 1758)
Dytiscus dermestoidus Fosster, 1771
  Laccobius sp.

"THIS ONE GOES TO ELEVEN". The lesser or Grooved Diving beetle Acilius sulcatus is a medium sized waterbeetle named after his superficial similarity with the Great diving beetle or after the grooved wingcases of the female beetle. As you can see this beetle has had eleven other scientific names, some starting with Dytiscus. The names of the namegivers are written after the species names as is the year in which the name was given. This is the most complete way of writing down a species name. These author names are placed between parentheses when the species has moved to a different genus. Linnaeus called many waterbeetles Dytiscus, and so this beetles name was at first Dytiscus sulcatus Linnaeus 1785. But the beetle was later moved out of this genus and put in a separate: Acilius. So the name has become Acilius sulcatus (Linnaeus 1785), with the authors name between parentheses.

The names indicate what the name givers thought typical of the beetles: grooved (sulcata, from sulcus, groove), speckled (puncatus), with yellow "ribbons" (fasciatus), colored dusky (caliginosus), "short" (brevis) modeled, smooth with grooves (laevisulcatus), or with short hairs (tomentosus). The other names: "the one of Scopoli" (scopolii), "the Scottish" (scoticus), "the one of Blanck" (blancki), show us that species may also be named after scientists or countries. What the genus name Acilius means: I don't know. There were Romans with that name. Maybe the name comes from the Greek aci, fast.

For some animals of the ditch the name is not such a hassle. For example the Water Stick insect Ranatra linearis (linea, line) There is only one in Europe and it has had this name for ages.

Not quite so for the Water scorpion Nepa cinerea. The Latin name means "ashgray scorpion" ("cindergray"), (Nepa - scorpion, ciner - ash), because of the color of the insect. But there was also the name: Nepa rubra, "Red scorpion" after the color of the back (only noticeable after lifting the wingcases). Now this name has become a synonym for the same animal.

On the NEXT PAGE: why scientific names .


© G.H. Visser 18-10-2008
rev. 30-01-2014

Valid XHTML 1.0!