SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25d45c541ab3c196c999fac1d56cc25b8fa92e164dfe448d74abb76823a6ff67' 
  AND token = 'yvt93j/1XwFVLW6a5R3xVKJq9Azni++7btgqWqAOsSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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