SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c774dd7e6342c913482c2d06c14d1b5f3b72db155dcb1239df56298f3803a07' 
  AND token = 'RF9lfpS1RZ0zbpobFeJuQYOJX0L5nWywvoR9539rjYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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