SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22629b75699ebc97322e42ebc45d572c024e8c47ac5b50a68afda70f3efe3df5' 
  AND token = '0ZxJL/qO8HbxtrQ+rGT1ku2KL9R1nnWVdVpyPGkr6aM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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