SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00eef996a40fe70f33aabcd82582c7289a3e46ab4fedb2da77c23022e985aab7' 
  AND token = 'CHohXzrF/5+w/vp4pPKVRRA8WlW9u/rDR7TmhBi6RTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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