SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f2764797330ba3b02cf6186eac24e4a00db34d3bd379f491da4fb2ab38ebd0b' 
  AND token = 'GblriBaG4AnB4JQnS3M8Kfb4M2BM5t9hkSZOLAybGhU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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