Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '851f58da811193d32094f3ec0f7fc8fd33d64334c6969adc98f8481aa1b6c112' 
  AND token = '/NcjT7XRPHFxKJwUZ9hx41qO123+w0srtfuQGIntRpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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