SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70c39244a1e5b9e3e35408dfe6e28c9a5f3b775098300fabf73eeb82d2936152' 
  AND token = 't6t8myv4sRYDz3oQswqjrwbkGHnnXrBR6YGerIaEBvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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