SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '57cd71d7e341af7041fd8038182fe3158ee2ac3a243aaccf265c40916e442a8a' 
  AND token = 'zcjAGd4WiHJ3Z8wMLf14FQXHwXvpChx/yFrVWfGt0nw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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