SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd64ac65aa0109f296dbead60682bcc1c0dd068fd1888ff07e6667115c7a82157' 
  AND token = 'nD0nBTxAWoUyuSNNej/oa+0yMmkaWETkVjj9zlij9/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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