SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '28dd82c5f225a7db4d9bb53b6197752b2d54547461c5b5a0d4c7a5604ccbb206' 
  AND token = 'SzZLmw7ExQU8KXVBp/Wz/XUT2vd+29o6B46T/7uxLnM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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