Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cff508dca546366a7934bb8f2d0990cdfff7bd1d238ee3229a8e2aae117c1d78' 
  AND token = 'eD7JWSsSd9aCV7bIiLM92LnUXaG83mGUYI6cnSxyBd0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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