Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '580b1ea6a91ee8ea0ab63d07339e056f15abf2d44baf84f5713eddc9ec53af78' 
  AND token = 'ebgSnhhflgJKCk8F6QEPoRFt0gUxGTq82My3s4MtMls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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