SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '381f32c2467847bf86aac1d9309f35a34a252e9bd221aec77f159bbfd70ea532' 
  AND token = 'fGlRLuh15NLZaXhgKh0rtNJvnd44QaNz5I7rBn6PYXY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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