SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb019eb34c58d5ca41c70c2189dd854d8ae8483377c4864ad8d8f19c117c0c10' 
  AND token = 'joubHpwVpq07JJOau5Gm8mAbCWlYFS7c6tjuwD2MlX0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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