SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddd9eda2b91045d29765379b5af684363aa42bf37511dc5a0e8ae94f3a91c5f4' 
  AND token = 'K/iSz112boB/kpqLmjkXIyS5oB9ghLpcT+qGH3SP+ms=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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