SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2525f50ddf201a6e52bbb5cd8a7823d044ff388d104bc0a86b72481749a3f30a' 
  AND token = 'XZIQtEWDvQJOE39XF5/kIFz7VLJ1cttKcGnY+3wVhic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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