SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a2ddbc82dd402a9c9cbef25d29da5080b0daf40b5860c0259fefd6da162eb9f' 
  AND token = 'xC7QcXOhUJFjqZVcBXGpB464qTCiYSy6U+voH2i/4BY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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