SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30b0c6a47d3a9221e7dbfdb0fc49d23d955eca0436c3f4f315571667dc48ce64' 
  AND token = 'AIUwQGs4jyVQcJ2HK3tpiM/t4aWNQ8KqK1gelo8mFCk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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