SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d778153cc4358f9bc8c6d8c8a31c637f277ad40fc932534728f838f7bae1eab' 
  AND token = '1NEM4KD/fYYjzm0QF+9WGdldyYGvz5kfdjWOTZb+lKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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