SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23b1411fee6839b4b76e05b6148d2d594d9d45d5133b6d27f5fbe9333463a33c' 
  AND token = '7N1pS/cT1Ngm7b0WHigdh+yZJVWSbcURxLEKKmiwsDM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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