SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3312b313ba38f758ce19a1ca57b15a39b437908fe6ba530016b9b231ab6913b8' 
  AND token = 'Lrjywdbq3ROmTfgXHdG5o92TBh3R7eByiNvyr/DV5n4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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