Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e21aa405516d4eaab9c925f5e08a0937d6e98c8d75cbd7cb83dbb072a4652340' 
  AND token = '9vsIU4/Pm2L6ey7lDEgfQnPZfpEnYzKB/8jyPFIt0Bc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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