SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80c498cee4b2c7bd321b9064a633ba0a57365ac9d4da859df392f9600fba385c' 
  AND token = 'jGeWvntPz9zuw+pdv9uYU1XgL0s/NG8AAQhG70yJdtc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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