SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3dae21bf319c403e3cdfc18e0100b4a032dc3dd2557297345ba6e105d1d65306' 
  AND token = 'o1b5/Nc5xzJZLxBOsMfR2mUT84+7heqEQYuuuSSYy64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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