SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9f6f02c61f4fb5637c3c4156605e48223e5b22b5d218b8df3db0bd423be1c4c' 
  AND token = 'y3ndtO88ZCw7sR1wdvWKLOLJuQJD6/PZ7C8ZjypVrxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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