Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '58088761fc3943b67b47814240cf255587e19042a4ee4247c09f473493b8c8fb' 
  AND token = 'tKpcVyJzsiicJl1klXMQppij1aFAATPXP4aP3biU+yk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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