SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '26c76aca707044c418ace37b30d35b91fc624a7e28c98f66e03d7e4552d71b03' 
  AND token = 'stsgjoMXPx5EN+r4HkpFVopPPBnqajUFiMw3NjbVZgs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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