SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'db622ae9fdee1f36d611c89b5a59548802d037fd27c827a0caf8ed2aab4b7590' 
  AND token = 'D7QWKUEBDpU88OtFBoPh5Zh/PIprOXWuKI67vDfxMBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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