SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e602f094792c516b5215b35039fa87c24c8248bca4ea0297ba7f10990b55df2f' 
  AND token = 'kJik6er+xzsWlDGOS+uwEnd7axGNeu4IF9bzNrODLh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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