SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66071cbed10e69cfed13d2e6c36a9712c757e4d62ed280bd19e7c14bd5e29f3e' 
  AND token = 'afaDZpC1kHycBg4i76iOhV4/IGqDUZtvLvr59+cQXZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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