SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '492c532be616446c4753fc100819c22f50818aafa19bd80385f6b51ccdf8686d' 
  AND token = 'zF81+REiOpyMkPCbaJJiB+Z05KqqdaI3VlQ/BjHARck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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