SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '97002c6055030820ebf6b2e60d66607b1169c9a31327f473b9824f1f214a9ba5' 
  AND token = 'Y4yavu7lJ9qRL3QbyBLaQeXmjfzIodfoZABcwGsJv34=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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