SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '585a2925aa77f98609f6ce289bce07412d4bb2c212829a23c9906644193ab866' 
  AND token = 'DK9VXQBSFyECz7AUfK1GMQ5qN/SYnwj20GDzPM+c4Yo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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