SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eae5e1101845c4787da7511307682dfa119ceadbe98f61197b43552f0919cd33' 
  AND token = 'B8q24/g0QtQgqPVMwHKPD2fZ3LJXyf6XpywYgvQeElw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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