SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af8ea3ec82b1a403ff44c3c7f135a532c01c6d677550404c786decfc88fe0aef' 
  AND token = 'RXQE8YdIdpafETcWSSK8nyUPoeghsutXpbBYk4hkhig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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