SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99b7efea9e07da58cd07e2242ce3c15da1987eddfddcd64d95490167c161f877' 
  AND token = 'Oo8NCILJFOk6xV5Tx6iXlYrOqhtYeWeaXE1mmKikS8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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