SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e0b320b279de351d83ea3ef798e41d0bcbdc6892ef4861673a6ca49a8722d9a' 
  AND token = 'gUTUwXxzhL1v5ryuOYFU2NDpqr+K48NF/9dGA9aJ03s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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