SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f440caf0d9041dad2b6a08ee554743ba565ea114b4a05dab6fcb80da45bebb7' 
  AND token = 'HGDkhmVzYFek7qA9/tNMBMoG7H6rCX/hhFzyaBAZGrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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