SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dbed9f923bbfa2b827aca51748d6a2e35cd42b59a50432a46c6b02d20ca8111' 
  AND token = 'KMDNQWUGLSEHq00InBQZi/AtnX5gPwT9jSs8cfiP33o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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