SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '003e0d5c8aaa17f96d8994941efa4c4665bcec65865dc734e77dae415e444794' 
  AND token = 'V/2QWZ1QKIFCp5oqg4LvbdPmFOSKUVu1dtkuSSDCH9k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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