SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20f1762f90b8ad39a5e09bab46dc14935748ebe48b17c5c9181eabf11862ec77' 
  AND token = 'dHK6uWdx0/FPEPigwyA0z69t62heUH6wKeU+jeKOf9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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