SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e52fa7c2bd7623fa260c96c3d3bcef46f6658890314d59d7d095db4007e48cd0' 
  AND token = '5xC9/uVOukIdxOFfX9NEskVIVg5TGKI3DbLe8S94ve0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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