SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d5002962e638c7bdedfc0a80854d8e4c88ac89db948478effadd2d31cc72bdf' 
  AND token = 'SYmGaCWUtuSnchUwjpetuy23SVMERsX09NxTT4XDtZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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