SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3556c295aa7f377061e6ab310a57fff959a33a8824b2176c214fcb29e09819cb' 
  AND token = 'tvyw7J0HxXPmozsHdkRQuzmc7y6DKhPpz7JFbEfwNYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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