SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13b48f26ce0585dd903afad25edcd90e6af45718d0ddaaa1a28c43f4e8de8245' 
  AND token = 'fM7ONXDgrqZOeFC1GRfAqtuTIwXCiNQ5HPok/vfaACA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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