SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b9f26e8f027aad6814a93e7f1f0e6b4ca5becb7fee8c7fcb5c03931327d2ae01' 
  AND token = 'yXAhDVFbuhuzjyDeJS/TuI9/EuGHESGRD2bUahWzoZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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