SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c08d7e77889c6b7a3f575df021973dc38982511f8ef836519bca19b8c79ab0bc' 
  AND token = 'iLyP0m6BUtKg7po/Vx4gWcDVT4grGF9PnxJUVNEI4/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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