SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '164fedc7651c3d47d134293fb60ddaf6c4b0bd4f3e08183ebf5ab87be84176f6' 
  AND token = 'rNDCuD4mQe78HRKEKMsC3kdC0Vg2ffHpfkZimvrEbms=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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