SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7737355c40adbfb3662716dfc522c60deb5bb1b149acd7118c767b64d687d06f' 
  AND token = 'UbU54ObDmImKyFfIuIwKHB8He6Pdf21bi/MTscH0ySM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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