SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64773d8b76909a750fa1a0fcd4341018b11301297fb00c969eae89bc9a2e1218' 
  AND token = 'FrhH5FJFJxXW3DwAQ8YgFtNLMKuKFXcIJOWC9RVJVjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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