SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60a9b8111b3fc656a4457a107af2e1fd56dfd56bd4128e253f38a706f1f03eaa' 
  AND token = 'M5W/EEJ16leF5VL/a5eklSSrJjYIzCiaxoKaTPdAaEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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