SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67b9ebac581b729e7d4e72ddca0f2597161275861295f1300b4406d9ccd12642' 
  AND token = 'hJcqlldfYjDtSHIwLCbcAbbmCJZDDyyFiFtNwjXRL48=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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