SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d753158f6c923c3849690c641a5c75f6c1cc3009e7e12ed34a84849eb3702e4' 
  AND token = 'xqZ/v/68MStzDNo/KK97lSD+VLXEPi+iqjaMSg2biXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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