SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5446d1b29acebd8527e85d39ce25bfdb584f8be6932e731afe33c0ebdb674b4e' 
  AND token = 'T0jAIAnMyICHirzHCA8sdZY8XOIipZIkNxJspifZrcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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