SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8dba436d6ba73301d1f08bf13939110b8abd884aadb9e2e89adfdd35bec33255' 
  AND token = 'VUWa8jm/YjYQIdq874Lf/m7hylFHhSd+AKTm/5Jzmpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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