SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '16a17b7cef6ae0b87ee20177b2a9a36064afe5a82aaf173a540295fe38c6372b' 
  AND token = 'Df2sbW0HEDNW8xuvxRGwusFerR3fAYw3hIVWZuaD/Z4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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