SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b179463dc03b27e16e5d03529007c93d56dd15779f22bfbb2aa48f024300a719' 
  AND token = 'nkNbDeyKts2w4xQmrPW6r/yrozKSsgVcTuh4T46BFgU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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