SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a0808c6ed1fd9db4cd1e9ec1b47dca649459329c890b17e5d8988b29d61bf23' 
  AND token = 'sxyLRdOwaXpJCE4RIwzMr1F0zb2Olqfk5NN5UXln9ic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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