SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89f90e6b647a3a4f1feaac97f1079d8e27fa0e45c89639dfd5ad22a5baecdbc5' 
  AND token = 'bKrzX3+OTq3sLfDL87Qw/GDFmj9GV+xDhsKflWwQkfU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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