SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ee7c5e7557f7a81bd456dc89fe4cc3292578de7e001eccbe2cd068f2b1da296' 
  AND token = 'Fc4Pw0PpLrsHu0dWCVYxUhaN7rjpycyMuBLsPGQdpZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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