Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df7f5dd7d982fa3dc541d34285a7d709f9fcca4af1201be0d878dd2d5b120eb6' 
  AND token = '9kVZsm3ehi4NFHt2g3MpaIcG7QZBDeLLc6+HgYyTFPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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