SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd30267a0f4102ff695253690df2beafbf4504d6f8ab6c8e2ced55f27c9c7e74' 
  AND token = 'cvnuk/8aRD4sFWxLJdK1eXUPCPIW6Fsq3hzgje8Xm9Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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