SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac0dd8e728e09504f5f7c969dc2fea06e601b176f37bec8161ae92027a4d209b' 
  AND token = 'x08OsLWBuC0DgtrwmLXR6G59LfyRe6RHWPgUUUd4GEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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