SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4141096cc739363d47c039d0b25e5c61ea8e46fec7539ff85381e936a619b48f' 
  AND token = 'slHzh0SK0GCpdC0qZvp1VZGG1gkr2S7YQ8ufh6/H2Xw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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