SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55100ba6dc9392dc1831245b4ff09a4701d76e63c7d04fa94a3bdd144a0ce1a5' 
  AND token = 'lUsJLXVR/5bCK3yw2wwAVKGhmXlqZwxxyx9TU+ksEQw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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