SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '054e81a5406d39301155abc767fcc42550ca16a7f7298594a5fa94873a7fecd4' 
  AND token = 'fJWknKk/tksyY5Yp+02mitpFBSAUvZv34IuXTQeDvJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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