SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5e4918b8726e1653ede13109e6bcba97cf20020a1703938007dad218ee9cd8ae' 
  AND token = 'U2hhIwDNrEbdZ1egS1mcX1BtfNYCLXKAxMWyeK8xadc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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