SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07df81125c5a0c171cfe361984803f4d0d47ff7ab765277a815b6dd043b144c5' 
  AND token = 'JjEU4vtz5KCsi/sxqCqvZeVjh4K49RuwB1tOda1Lzm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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