SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9859c81957cf37d4779938ad0d7cb8a410bc4584c7bf511eb2b4c5ac98d3ccac' 
  AND token = 'n1aotiORaSFqDvGRewj42ZqgTQgjTf6y/1C0wmbrPGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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