SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4af7468986dbcbd8c8fda5fd35696faccb53ed79d1b5defe36f861c56ecd1602' 
  AND token = 'Sp+TF1Avsr/X9qQrG5KnQFzThTqQzLwqQ7p+4ZNTwng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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