SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c5eda963288e5a6a9c4eaa112a5bf6979b754507d52cb1abe8327323762ebf9' 
  AND token = 'LAwbbbloLmLwhehSzsYTetsO62+wXsGFuRAG3qbodP4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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