SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcba36c16e6dc2f1940aa2434c10ae6920f9971272bf2ad6853252a442e897dc' 
  AND token = 'wVgcMYWw6zPgD30uK2XJVsIXhziX69ei6xoksSUW8hk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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