SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb76dec71cc2499f3d7fe02a9d284f63d633f0e5c0cf3082a4bc3aa126ff6674' 
  AND token = 'fe1BWBmyFsUgCYKUa2494bQP9gZSQuZeFz9UygCWTFw=' 
  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"
    }
  }
}