SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '18dcf2c6ea82aa795a28fabd37c16f4862888d0326de18201bf2738dfd88d4c9' 
  AND token = 'pugXhLiu1GivigHzYtmwNZA+QU6+wdQUiDv/vqrqWB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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