SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1dd1c2dba4f308af8c8bdb1041b3b7a33ff73d96a7adc080e178c07bdf4f535d' 
  AND token = 'ZkYog3pCA47ea7pIew8IwgU5DKOdlzXeCfj0tIM6LoM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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