SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdb7336fbbfbb0323a7475a93ab43853825ae09e73828255d6c4bdb31e46cb2a' 
  AND token = 'vWfwvhmgZVDt/V/gDKmP3ZTakDFp+plMNmORru3wqNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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