SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9683952f64c358d3d993cfb85cc7e82af7cb60181bf2b63bb1373bd3a09f5caf' 
  AND token = 'Vb4q5+j6Myqx5m7ARArZxZlCVQTivXki8LLo5EZGq/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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