SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '149b29ab6c521477ceca92ef396a00078797f45c9cbf160fe097263804330f5b' 
  AND token = 'mjmZE4vnSkI0pFVm5ftDtvrwnhFpqqcJ110n6gmvHes=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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