SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ee5fbc10b70fd24072e545f08ddd061663b2cb5688a8b0003a7e95e893a9dcf' 
  AND token = 'Sy2gGyT/fdqvPxnVKUtiKiCnlgr7NR6tueBow1EYdOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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