SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa1211614a59f91038938ec2bf71fe6f23854f9844432c87555045153a07c003' 
  AND token = 'Q2XUGpfgzaetPH/F33Eeo0k0u7b9nIe+13QYHmduZKM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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