SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25190bfd8b940dbff038539e7b674c81bc07977983c6b15bd9ae293710e5f815' 
  AND token = 'aM8M4Miow3oRbs5Dn4cDw7pYDyDsUe1fznvC7HGPW1c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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