SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f0e1da8cd9e279cdc928d56bf9cfd8ce12a30256c4bc1939526be7dd052b65e' 
  AND token = 'HW2aYq4aN5k75tgQ/A/lvRyH1aKAsfB4JBazwpmsFZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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