SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '567c25a6c1de6a22e5a38337103ea55b16c0cba973530646cfb7104a5a53401f' 
  AND token = 'sZiqA5AHYRDlYgIf+jkr65x6YUPChFHzGo/ua0sxM24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}