SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdbc7c0d9938c35c25850c2533c7505f1326772bdf336085cbf875c44e400467' 
  AND token = 'eRoXLdtX+SRMNKIv9RhquQ6RFTXwBiP9jbyqDLfDjLw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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