SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3829eccd795c98e196c44bc58724f9eb5b5772d2a4910d8015bff8b62ab417d9' 
  AND token = 'OspGLBrnaCC/IScZdfl6aJdPyHPdQUGzKAqVwPBogE4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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