SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '066ef7d546d45026a9c7f4bb32b419fa2e80ac56b34d60e920f331d80d19c91a' 
  AND token = '3jUgZHORhOQ5tZW+nvo179GG1BmpmPGrIKrzIAyfa1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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