SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '62345cf7aad1c860528344fb1fe203577e7df9c8fd297dd6d7b0ab0a673c628d' 
  AND token = 'f8tYaSnUM+WqWsBQuJf9ibttf1meKYy/qJdfpHpGnIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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