SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '439acf1d13fdb50fc18337362de11d9821dc8b38d8a5879ca742c278bd121cf3' 
  AND token = 'Tqo3TABW70g6dWdngmquhCA9ecjNg5bQCiuozshe60s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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