SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26d9c24c3037532b23f7daa70d37ef05f9546d92b9e063d93d2c685305c0299b' 
  AND token = 'tgUqfKB/D0GqyTQ1Njzo27N+7h9tdaE61H6e4Xkq2CU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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