SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '238bbc2a3ec8a54ff22c5cbaf85d445157c10683abe661c5ba21df29820beb7b' 
  AND token = '/ZkGuTSawMxHFU3Smeq3vMAAK3ZVPVXG3wua4MZzlNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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