The testimonies on this matters are limited, but they are none the less quite interesting. On the religious observance of the Lent, and of the vigils, and of any other abstinence, it was very lax or rather non-existent until the Dominican friars came to Hispaniola in the time of the II Admiral of the Indies. Bartolomé de las Casas, who was of the Dominican Order informs us thusly:

And for this whole island (the Spaniards, I mena), was perverted from the Christian customs, especially in the fastings and the abstinence set by the Church - as meat was eaten on Saturdays, and even on Fridays, and on Lent, and every butchers' was open with so much solemnity as in Last Sunday of Lent - with their sermons, and more likely with their strict pennances and abstinences, reduced them into taking conscience of it and abandon that gluttony in the days and times the Church sets

As what concerns the animals, most of them are rather straightforward, being easily identifiable as land animals or water animals, but thanks to Gonzalo Fernández de Oviedo and Bartolomé de las Casas we know of two animals that were of particular interest: the iguana and the manatee. The manatee does not offer any problems as it is a water creature, but its meat does not look in any sort of way like fish meat, but rather like veal. If you did not know it came from a water animal, by looking at a plate of its meat you would be inclined to think it is meat and hence forbidden in the time of Lent and other religious holy days.

The one that actually had some controversy was the iguana, as commented by Oviedo. He considers it meat, but would very much defer to the opinions of the prelates. I quote: I say that it is considered a neutral animal, and there is some debate on whether it is meat or fish, as it dwells on the rivers and the trees alike; and for this reason I once thought I should place it, as I did, in book XIII (first print) among the water animals, but now I think I should place it among the land animals, as it conforms to both according to many; and even then, in many places they eat this animal in the days that are not of meat, like Fridays and Saturdays, and Lent, and other days forbidden by the Church. But in my opinion, I deem it meat. I don't say this so anyone should not follow his own will, or that of the prelate, or whatever the Church shall command.

Bishop fray Bartolomé de las Casas is of the same opinion on that animal: The Spaniards commonly say there is no treat so tasty, but I cannot say as I have never been able to eat it, not even in the earliest times on this island when there was much necessity. They eat it on Friday as if fish; being it raised on land and in the hills, I don't know how they thought it a fish.

In the end, however, all of these controversies were moot. In Spain there was one special pontificial bull of paramount cultural importance, the Bull of the Holy Crusade, which allowed their owners to forego the obligations of abstinence from meat during Lent. The distribution of this Bull of the Crusade was extremely lucrative, as it was basically required for anyone not living on the coast. The Church in Spain made an absolute killing from the bulls of the Crusade, as mentioned by Francisco de Enzinas in his memoirs, where he comments that in the Cortes of Toledo of 1539, the commissars of the Bull anticipated a sum of 400,000 ducats for the triennial distribution privilege, and a much larger sum in concept of the future benefits on that Bull. Not only every household had the Bull, but every family memeber was extorted by the commissars in order to buy them, and this sell was yearly.

This custom made its way to America, and the salesmanship tactics of the Church made their way to the Atlantic too. If you owned any slaves, you were in for a commissar ripping every penny from you. Let me quote Oviedo again on the matter: And even for these blacks that are brought daily to this island and city and are baptised on the next day, without them knowing what is faith or the fathers inquiring them about it, then come the commissars asking that should we give them meat during Lent, must we acquire the Bull, so these newly baptised blacks can eat meat during Lent (as there is scarcity of fish). And they charge half a peso for each certification, and the number of these certificates matches the number of blacks.

On the matters of absence of wine or absence of bread for communion I cannot speak, as that concept is something I have never considered, truth be told, but the question is really interesting.