SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1c6f2492b2e8caa84ae09033d8bc0b9f37f28f2636c12d3b347ae432fae131b' 
  AND token = '3D8d5BrrEOVEaL6IG0HjcUwzc8b1mAkypKMluhd75AY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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