SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dcf061c9ff8abb121529de0056bea5830c71d6cead1e6bf3c5ed67894513d56' 
  AND token = 'XQAPVW/sGlZjrM/XgNYG+j45j+zeUjCGAEqGxRssVbI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}