SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb6f3c81328e9beb609ad48e3fc5d8457711bae1649133135c503ee910d16c7f' 
  AND token = '85gwVW57whwOclzLnBYY7AL5tVzXmpmV+1T34UfQulg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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