SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89df7feb7f484ebf3c92c87f8d8cc86785e07d7f146a31ad4206866780fd1daa' 
  AND token = 'JHgI91wN7ZI+w9i7fyj4VQ8JVPorcWqU75OsPvHsCcE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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