SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb9064601cee0402a16213709b7dc11873f7605f1b63e8db48457f3d0af00c0e' 
  AND token = 'rHMB+A5JChNZwZQhyFACjPHqOzx7i+SMgr2ppF7KMU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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