SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24e99f7c8d1617942e8f3ce045f27066ef49a38fbb265ace97eed68d185d8f95' 
  AND token = 'qEfDUcdQoFlQ3KJWya7HvRvz1RAYGjXWS5DPYn+Vs7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}