SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6745e7a368213b37a2c4b7917219c60a775b5edda5c59423cea4a14ca5d0d109' 
  AND token = 'EYSArxvbwEvvn9gt2nOIr+SUp1rHiVCYgk5SUmt6kHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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