Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b93c896e894d8497ea66664fea46700664afbd851638bbc02f78a97d156b4b70' 
  AND token = '7ENqIvneSsbd/7IbYwfxM5DmN9vMa452x5afspEtiQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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