SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '522c192ad2e787db618558a4782753206d72b681c682927d640b60179515ebdc' 
  AND token = 'dxKvHxTp15nfEWQouj6uLNLNlahObAp9MBZIpPMaiqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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