SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72acf945d22a3d35e16d65de8ab2aa1e51268e307a142b56acb5c1e70b8adeae' 
  AND token = 'GxXvPidNc9+kDMnP1HxY/hObGNoK7velKXFgn3iQ7v8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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