SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daa9a43ca42e373eb3e54042d03cb8ccb412b3316b2d91fe5b853c4006adc4d9' 
  AND token = 'ylENZv95ZzulhqDzh2aIHgME2IMvyybuveuGBPzstFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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