SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8826545fe19fd8db895cec6558b2e6f637cb521a81cc00540406f0eb7774faea' 
  AND token = 'GZzgSc6uoRlVpJMLLkaCDjfYe+AHtNKcVo/inRrBGZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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