SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2ba74d1e9a297dbaa47d82a756e9b38ea9dae8e5ea4f0580f61086000a3e60b9' 
  AND token = '3AHsnLyDJtXRtl0Z76LEvNL0pkMPzGmVs94dNbT51o4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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