SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5af02cb3877806ae36bf57c8af4922a4236d8b8e177c8b9d73a07fbf41846e92' 
  AND token = 'm2qYQ0OAKyhuXRW762sgIVVSB+qMW2pbDnLwbU/cX2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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