SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce6a4596ff7b81cf21ad425e61dd93e85807e964983f1f7293aa286ce2e292ee' 
  AND token = 'cRglHb+ce38pzKRjuCY0AqGOYKvV+/qbpAAtnkvd/90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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