By Topcatto
Panama 
Planted some marrow (english veggie, like a large squash), some spaghetti squash, and some Martin bird-house gourds a few weeks ago. Got some nice little plants coming up, but after first few leaves, the latest leaves are "stunted", they are so far only growing to about 1/4" diameter, VERY close to the stem, and VERY thick! I don't see any kind of insect, bug, bacteria or any thing else to give me a clue, but the common denominator is that all three "squash" type plants have at least one or two plants with the same issue. By the way, I do like in Central America, so we are in our hot/dry season right now, so I am manually watering every day.
7 Mar, 2021
Answers
It looks like aphid or mealybug damage to me. If so, there will be masses of little round green bugs, or little woolly gray "armadillos", hiding among all those distorted leaves. Accidental overspray with some weed killers, or a few kinds of virus, can cause similar damage.
12 Mar, 2021
welcome to Goy.
Have you had a recent cold spell, this seems to be what happens.
when the weather warms up they should start growing away again. keep suitably watered.
8 Mar, 2021