SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b60f27fbcd2e92d9e145106a81d1ce54d57f7ee61cc6e10126d7799bdbda7b2b' 
  AND token = 'iseDsKqA3MaBioUl4Dft5TvUaxRSeA//tqm4TZu3hKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}