SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '655bdf3506b8c6a7e6c1e34eba39964da53ea37dd128642e3c79866be68ae166' 
  AND token = 'UQB3pu1vAeO7i34FtYe0ek+1fxuCTVEuJSTG6ofJXSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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