SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d8c2c794b3634c4484955d062ff0aac6f12b044fa1266f5a8d4ee627f7dc07c' 
  AND token = 'qKUpFnYSCp3GJnqwi92yzZguCcgt5ChqfmZVKmlVcmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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