SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c08a3bcd361d09c9cc05649ac22ff862307d23489bc7f495a7116bcc7ff04f6' 
  AND token = 'UGm5ybECdcnewHr8zI8kWi/wAriUE270/odiS/VWK5s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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