SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c30718933c92d743077605034f08a055b6d8133b4794f434fdbf22122cbefdd' 
  AND token = '8ptXPZYKcdUQHL/TWlUY3mXe7VRH4GLdRpT+Ug9hLUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}