Monday, December 11, 2017

Case of the Week 472

This week's case features an intriguing video by Dr. Graham Hickling.

The accompanying questions are:
1. What arthropod is shown here
2. What stages of the arthropod are seen?

11 comments:

Anonymous said...

Impressive, the species appear to be Ixodes, the nymph stage with six legs morphs into the right legged stage.
Florida Fan

Anonymous said...

Oops,
I meant eight eight legged stage.
Florida Fan

Idzi P. said...

I think Florida Fan is correct!
I’m rather sure it is a tick. I don’t dare say Ixodes sp. but it looks like a “hard” tick.
It sheds its exuvium as a nymph (six legs) to become adult (eight legged).
Very impressive video!

Eagleville said...

Ixodes larva (6 legs) and nymph (8 legs) - speedy little critter...

ali mokbel said...

Well, it looks like a nymph stage of a hard tick (class Ixodidae). It has 4 pairs of legs and a prominent dorsal shield (scutum).
just a hunch....I think it's a female hard tick because, unlike male hard ticks, its scutum does not cover its dorsal cavity completely.
Yet, I'm not absolutely sure about that.

Anonymous said...

Agree with Ixodes. Click at the right time and you can see U-shaped anal groove inverted over the anus.

Deborah Lazar said...

Ixodes Scapularis changing from a nymph into an adult.
Just a guess but I’m going with adult female.
And in a hurry for her next blood meal.

Deborah Lazar said...

sheds its exuvium as a nymph

Anonymous said...

Thank you Anon, on full screen if one clicks at the right moment when the tick turns its belly up, the inverted V of the anal groove can be easily seen. This confirms the female (scutum covering only anterior abdomen) Ixodes nymph with three pairs of leggs shedding its exovium to become an adult female tick with four pairs of legs.
Florida Fan

Anonymous said...

It would be a nymph of Ixodes sp., (since we can see the distinct anal groove embracing the anus anteriorly, Prostriata section), emerging from a larval exuvium with six legs. Also, if it were a female it should have porous areas at the basis capituli; they do not appear to be visible.
Fantastic video, by the way.

Anonymous said...

Nymphs lack porose areas on the basis capitulum and have a scutum that covers only the anterior half of the dorsum, regardless of whether they will later molt into male or female adults.

The video shows a larval Ixodes molting into a nymph.