SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4cee287c370e63f67108461e68f5a14bb446d6573b47b502f7bc1ca86485699' 
  AND token = 'BoEucibaMLas+a354sBcdDO40nY3TJUHAJVFFqlaJm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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