SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8085489f93bcb5dea8962a44c0169d9a94c60b2e61b04fa346487fab719ddcb7' 
  AND token = 'g0AMx5hKgxvPAGwQI/XLV1IB8WnNhFtkTjMInYXzudA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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