SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fa5bb78585812c0bddfabdae9432bcf36b7e8a7ac6e83f38305af05cbc0d1be' 
  AND token = 'xLWNUpvJeNK/vV49IgXzzHJeUh/1knKy/64gg3XxtJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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