SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86b08b36dc690dad112144c03f124ba66fa9845ddd5c7c397509cc6d373f8682' 
  AND token = 'KXKfQHOcP4+hpUrzxv8l93XX8FA+ROow2y+BJRAhIYg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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