SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6251c24768895427086280464084310a8aa2d56a0e896a0ea5bec0bc5708d471' 
  AND token = 'YFJCplJXTFYR+kp4t+WEHKe0Al8I7jf+YifLqOBJ5gU=' 
  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"
    }
  }
}