SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1263bf22a56c09f4f6f93f81395ef1fb4e7e1e10bf002273e62573d3daf19558' 
  AND token = 'DYnlpusO44/dKBlU7g0VML5HWQHM4exUhHjV1niZNIY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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