SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '0ae05914b0ed748d5bfb236b05d1b398a425efa8628a7bf43daac46e8aab404a' 
  AND token = '+puYP5h4FGDAPvKCmT9nYhQuh/a4kkugOlulG949kxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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