SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '561d905e1ffa32ae61a05a61e941e39eee5ab9416082476848d4d587be70e36a' 
  AND token = 'g11rxABms5pL41y2jgSwCt6u+JmUHiKtWQ2nlw0BiCg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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