SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b49d0dd9fab4714983faf2e51229de25abe81cecd9c7f80730fcbb5ec8158a6' 
  AND token = 'RZxuTYJ/+qC4HZWzcXudMD+SvRmYAYIzNQlfBMM9Bsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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