SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46fce826f20335aa787ef8c0e5d17775882f928a857a3bb30eb36751f3c4a6b0' 
  AND token = 'CNItDQYrp4i1ytj68wEMucfUzoCd8FeYPWEpTVEM8Q4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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