SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cda918fa7e1f63f1270253d22d4f255e73285693b99a68a375047d016f1b56ce' 
  AND token = 'zwOC5SKMPhYNCbEH9ZQ/4VhvgaUqgKSmb60WGDa5Kjw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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