SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cefabbc3e58b1c79a57a005f9c71926ee191cc5f6e68f11386656d899207813' 
  AND token = 'MyywTVnTg7NCmvnBKHn6maEPkZ7tBCaZhrSvyQqSMZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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