Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'd29010805a88d20b85d472ca74ade0034073d9b3eaa58345e808262ff848ed02' 
  AND token = 'XTS8lskZHt/dIJ+Z1rtlL2KqrJdIgFLd+xF2lQAybvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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