SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ef366eb6d88810e469c29462a0766e65c62f19571a6cc5c75892749a25be76ec' 
  AND token = '4ugqoAOTVtrTQqMeOmYqtEBpIa0Eo7VT/TzvtZZmU10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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