SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6c63782abbf2297d70ca29a1382d5949eab437259469aab959358591ebd3588' 
  AND token = 'RML17QyAsjCBtmY+28xIzdev9sdsoC00P3KKIzMzL6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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