SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf4b9d8f4d86f5d4c9f4b7f54dd9ed0733b28ebb41ddaf0e5840b55e928a2dae' 
  AND token = 'VSwRbKnWwP2zyHZxuVU1ATbtPat/O9pV4Y8dQP1pmMA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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