SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be5da7921386eaa6cae633df426f3586c50d6ef7b22a0f98a6c22ca7a8129470' 
  AND token = 'affwHzYm0eikHQPG+QLk5F7TVI/BkWpi9K3wnNvaTAg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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