SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'faaa8cc04d17d2bd73c06d563d397afb81026975708a39ca768629ea3c73a1ba' 
  AND token = 'WklSMR0jdHYJQ172kqMlKTeBiyBhGUor+CbIpsZlUwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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