SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ada9cbdc0effbf121659bab0fcf9dc57455319a83a62365a3f7c5269db0fbe8c' 
  AND token = 'lOgl56aGBLwR/+JLaY4yVtQEJQZabzKCNGvi5mEtbrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}