SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '81baff6c7b114ebf616a1e146ca70cc312fa776dec5f59ea1fc23d925a96c19f' 
  AND token = '7EAQhv9LKxF0yoRrgH2amsChuf39/KxHI5TE0GlVaJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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