SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f461fa8be1772fcb010e96f987a3364085a8e4f292cc943a963c921d2d07ebb' 
  AND token = '0g6nOtA4+RDOBFA9m62kLCesFeA7oW+7i4t6Q2eHPG0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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