SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80a161bf026fc2ef8443ad724b6b75a6cb04c51fe07ddd3d482326a8fe8dcda1' 
  AND token = '4CJHSoNjsywhSpAgHJekJvQW/6rKVmX+NKzO0QiTC4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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