SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dac227eeec89254290feeac76a0810798539ad077a6f8e5df5a0d51e333aeed1' 
  AND token = 'SdqRGoTfLf3HZvcfVF0Y0xeT9W+EGsVgshDzW0eRSgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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