SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd4d3fbc14b71c36589ea238660e50a88458fc2494233eb60d651999710dc09b' 
  AND token = 'iiuxlkZ6sPivmT+L7VEBelb6R3ecpayQARAG/tgXpvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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