SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a8135e7bc8de2e780165490fc40dcb96d930fd8b050e54a14e9475e75edceadb' 
  AND token = 'kczPPMQUHBEL4A595D4VcUi1/bGHHZSpKYryhyMCNDc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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