SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c7344af7d1ced59a9afa3f62c931930004f374affa32b25e1d1a882ed6e516f' 
  AND token = 'qTxHlPT+fZkBMxtaJsSv05A5xdt6ugBjgFUgJXHDUJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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