SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a03dae99030a0a67d7030f93e81005a854935f7db99536efb8ee5ff4f02058ef' 
  AND token = 'XaH7ugD2YkD9/FRkij5B7N5378EhKHufUfdzzpORo/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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