Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '4ef18ac6fdf78c84ad80524b94ab8cca017db2a3244e2dba030cd1ac8b9e91b7' 
  AND token = 'cYNzuNGM2FZKmkSWhPfhmgXTaIrMSQ0hqqw6mw6g2OE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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