SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dac8b445a6f56bb003687916224c0ea0240b8c2e2f561383fc1d901bc1863dca' 
  AND token = 'Td8deuNbOb2wJLrimDmOSZfre4+VXI8xJHxEV2NsEbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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