SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea8e1ddf49ddb10c15a97f4359c5c30c2de6f57f1521f9a301d513f61b1c0f98' 
  AND token = 'Nl1p4ljn3wAkGugqD5v+MtiFIJpP0iJ1O5L0TZdbcbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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