SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aba39155cae0f2d4cd2738dbedf542bd0c762f16109b3e5e72bbeba6df6e86e3' 
  AND token = 'bLTFuLxZPZ/b7zspktjOYLmEyvvjZEtYBCy1Ku/fUe0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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