SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e865ddf10d5492a9be90ed0287bfc7dfd43dd46fa99bf752a32715cc15c43988' 
  AND token = 'uYfRhjdBzwXeeaUmNVu442X0RJsJgOh3FBomvM2BRxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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