SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '943a1f1c0a6492f8773defe448b171e51b37e26c8df5bb6ef1b8c58e4c5d031c' 
  AND token = 'ziOeTmTCY00p9XnJWkyh/VKVBFUxL3hzb4ejNEKABXw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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