SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb025553f8b703e649b1fb1819733d47b92e0c983a3f69f4d4bbf3f0cf6521eb' 
  AND token = 'Z4ECGzngMhDzqY/Na9HUozGv1kTC8EzyeKnS+h2pO4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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