SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '10526bb3011343f481d4788d73471b0d44136c46e421ff14f4f86917008f8e93' 
  AND token = '/7eU0rgRSqi/u0yTDKRkQrRn1ZbkjwX+ovKKjViYePk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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