SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ff5dbbed8f070f83e26aa1c62148bdeb7bebf838eecadd74307dd31e6df5b95' 
  AND token = 'odEaWaVR+8/ZNdYQj8Fq6FmhVXWmTcx3iPPvtjnvwTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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