SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f36e5bf68248607dcc6ff8a3a3a9e034da50c81e572107f2985277ef5d75a0ab' 
  AND token = 'ZAYaSXmt3RnwhCeIdXo0pEA/7bVbKcQjpWtyuo/uj3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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