SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f747db9964a8b31b6530c88bce7dc21c640c0f452eabca7ad194fdb144a5b367' 
  AND token = 'lhwnrfP/v+fpAX8ULXZR1Hg/U7gU7cIZZ4BXlgh3gwE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00092

JSON explain

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