SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45c92acdb3aca216b1847bc69cc7eada1014a8ec96fc2885ef193c4917886f6a' 
  AND token = 'VZtwWXJBM3yHXq6rFHeEk1oqe5koEtXHckiTvr8CH5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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