SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '457d5bb4063ad73e78497a25c26472724f7f0d1ddb371b591e1a9a3388e2e3df' 
  AND token = 'yEUzU6G6ZQDfcVKHnE6x0mBSiwATBlGtESPFI2a6vsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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