SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9442342ef0efb3330a8e01cf394149b57ae669d596391c8f39f361298a0805ae' 
  AND token = 'XhbZCllYeBHErwCAiv3wjXY04MMU1v0vJkxTZ6gWUyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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