SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4512a1ed9273740fed2e9ab86f901ac6811a678fc6622ecd520607a287e7df9' 
  AND token = 'ssy2YyecHBwwI6wAhysoKPWswLGnHK2lGJJxnuf+fSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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