SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7222b8bb6366ec44da7f10b9fe3a7651b2fb87ae5d30c93d7eb146dc3fdbdc2' 
  AND token = '6itWSyqe1WgyNWAl7ViFolXFBZa+LiOMmnNzDswjtJQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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