SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf22b409d28d79bcfa00c3337b5ca2faccda3d52e8274f853dabffa29d7e4636' 
  AND token = 'hAP8BMAOyQXwcXrNPbz91EQICGSsVxtQKbFS/tR1QQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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