Is Communion still Communion under only the species of wine? I was reading in the Youcat that 


  Communion only under the species of bread is also a full communion with Christ


I was always under the impression that both the bread and the wine when consecrated were both the Body Blood Soul and Divinity of Jesus, therefore it was valid and acceptable to receive Our Lord one way or the other or both.  

My gluten intolerant mother-in-law told me this so I'm not entirely sure if it's just true or not.  I for sure that Christ is fully present in both, but I don't know if it is valid or acceptable to only receive Him in the wine. 

The passage in the Youcat may have been in reference to bringing Communion to the sick, so in that case, it's not normal for an Extraordinary Minister to carry around a chalice to bring to shut-ins.
Yes, but receiving the species of consecrated wine alone is not common.

During Mass, the celebrant(s) separately consecrates the Bread to the Body, Blood, Spirit and Divinity of Christ, and the Wine to the Body, Blood, Spirit and Divinity of Christ. Each is equally divine, and each is the Eucharist. The priest signifies this by taking a piece of the host and placing it into the chalice.

It is recommended that, when available, the communicant receive both forms, but it not required. It is recommended that, whenever feasible, that communion be offered in both forms.  But it is not required.

Note: when presenting the consecrated host the minister says "The Body of Christ" to the communicant, and when presenting the chalice the minister says "The Blood of Christ". This describes the physical form only and references back to the Last Supper.  Each form of communion is the Body, Blood, Spirit and Divinity of Christ.

Reference:  The General Instruction of the Roman Missal, Chapter 1