SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b28c2ea9421fba6e89c52d526f427a9601aab87485675c9c6bfd2a92b401f5e8' 
  AND token = 'T9c4b1zDzZrwtDIP3LJn71ERhCsXOsFYFxsU//lNQAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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