SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7652d71e8c06acd133c44b7fd5f6516aa48b5502476df195ac26fa41561ea391' 
  AND token = 'nDMPgRVSKoV49BYhW+SUjHGCWtVlMngbYoQqbmtIrjI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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