SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee92ba7703c07b009e7586cf049d58417ccba6ffe5ce88af640fda47e1956413' 
  AND token = 'vGPvkBbQPYzQX1U4EF4vpdeqKbCiGchiGZ+ul5JA0rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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