SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38babcf2717efa97b645ad1ffebf37f7ba483acb0a5ad3911087c22a686187be' 
  AND token = 'dmhB2R+fTu7gmJxFHn7YXHN+WkWImSiQ6hZvzlzwNxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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