SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '70ce4d2ea0b1c62ae25cc5ac6b5395029c437d628aad2ce902a382c71c7def9b' 
  AND token = 'PujP241DTxUDqU5DQAvrNGFiRrq7zhtcosixLYbKjJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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