SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1152695c5c6c3757b6fa95b6ae0c05abd60267608e97e62594f6bd915c0201b' 
  AND token = '5Vl3xgy1zvaaBhxVK4hTv8L0aa3ZdMyhh9BFIEKWOEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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