SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82a7b2eeb3085802118352759503641c1940fa7316b7727ce7429006eb698d47' 
  AND token = '5Th8ibQNQAnh0M5CXUWPqsUMWbtqrwumi230Yz5hOBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

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