SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aee0e17a680a79a28c7652e1ee633766d3af94708dc71701d67746d3f5aca845' 
  AND token = '9acod8TA5Z9EXVtCXTDNrhJZYPSIEPeUZUNR/0ZN9IA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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