SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c1ce5c815da442969d066ada92b5694c95559ca666c9f04c6841db19b8ed902' 
  AND token = 'GnGNfslvejTSfB/8qdGOcM298MkjLoWHC1EgvhmK1P4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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