SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da24b74ac10d0d212c7c78d89c65f788f0117b9251e170a69cb1eaf9fd3ec705' 
  AND token = 'QcOLUnY1I2IneKateMBeoUp/92I81lT5n6s1hKxlzcg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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