SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '195e1ef7dc57841a30e7f1c66a4fd4cc189ca9c282bfb7e03f73f72477f79b14' 
  AND token = 'ACZjU5S4XVlLZQrOWsRJuzmVzlN0MY44+VMHhmZrwGw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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