SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2316154481868d08229908177b7bdb1450a5a8fb145543e368d5882d17258e17' 
  AND token = 'IPgI1uRPR4GxJkyt37HomUFBrboXQggKia4rJC356YE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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