SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f72bd89ebae431c59d46981bf21dcd6a4f3a5514e5eed59deee7fe12d242fd1' 
  AND token = 'HiaIT/Sk9EsyfTe92zL6uqB+mi1NnoUJTdxqMNHlddU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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