SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '579a8f221431af2b2eec86300a7e69292ba9bc765d444038cd10bf0bdd8ff5ce' 
  AND token = 'QQMazh/tK3aaGRd10w2iBDmAr0PqzwMN/ICiUpHJzVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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