SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6915206a379153f2592162f87c0d6d49f8919ba5888cb4d753c707c0603606b1' 
  AND token = 'KzZZD1Z4W1pO2rpM4nHyBAdOgQc6OxI+7nTqJ0if0/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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