Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4b9ba37a3bb4714e709f0da7578079bb8022c2776d20ec15afa16382ee87ccb' 
  AND token = 'aK6z2TowKC+rjfX7AEPjfQeQYWAOVsJ2LJQBLScfkE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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