SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '917687bb2a1f25f57d1fb2efd7423c29a9530e773df9e48f561be417cde12647' 
  AND token = 'SftsEGA3eQkGI3B6JHUVXT6rmfLSAThdDq2J672CzIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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