SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fb55570cf75598ac4a3d762a8a03176adffe2eb35c1de5e72abe6439ad89508f' 
  AND token = 'e4jlRQDOjABRIehOEyFNnJYj+/l1vKCzXVZFKNihyTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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