SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebb26f417c6b829142d9b9edbff528cc4ec6b9c5eb65e7fb713bd02e31fb72c3' 
  AND token = 'lr7ynnLV0XstUlFWZs8H4AA0TeyLfqWGkLAw8CY/AeM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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