SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8b4ef5167e2a626d09cb14ea683f0c709d2c33e3dd56a7567cfbe8a7dd9d36e' 
  AND token = 'HnGAfFbSZrE57K+RFV+DQP3hJtiYv8ZjJpwJZbOZU1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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