SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '915935d788d47ee4c72151e1527bedba05938cb26fde1abb1f19f2fd619b3573' 
  AND token = 'n2zmW8BWFi2j9GhvxjzZDVNCt715sJZjzmw8HvaHoBo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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