SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d5fed5e9abf7c6d0be03c8cbc697909a7a8badeaeb21a92acb938df409554db' 
  AND token = 'funbrUJeGrk0GNkAaHE2WeuRX7CAyZtVO0JA5eHbU/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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