SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a7d0a310ebd8ce7b8c3f19bb98dc34340800f6c6185e7fb7456bd86b684a0a9e' 
  AND token = 'oKL2T/6vqL7ckG7s76sgrJyAnwhDViiPJfG/7tnaKxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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