SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f4082a576f6285f6f9962c187cbd27ee4d8635d8906a19ecacbea5355db8b9b' 
  AND token = 'cOYZUIBL2Gc6qq//oZirdnLwnJBX608NvYLUNGBMVcY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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