SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c80672a197aa0c9c2e132f8fd3be56e46279e4eda002204dd0829cc5c4f2b9a0' 
  AND token = 'l8qR0tlQyekdvyxhg1JEWKdAUZcgZeCIRdDObvAcUxA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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