SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f7491ca55354341d7c906254eab6d03ff82df06381ad097162b73f594b181d7' 
  AND token = 'Kpv2BISWfcXg0v/Q/UkE261CJI+NA1TJWl9kcY6VgYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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