SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3cb42443765213b0c75e57eb8c7e2398a15a042299dc42c337bb22afe0142ebf' 
  AND token = '4WYs3DGu1itfQYW6UCbDUl8mIrot2fNiWyRZaMFrMGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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