SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ba57766d4272c73b9f7d575dd9b6dc863e56d99905ad80705811a76d21b304da' 
  AND token = 'gjsVsLvXChZN2SHCcHqaYJS/pU5JKgXQgPBKf70hDtM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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