SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8ccce471965959e7a0f4d35463f7d955d8066957812e72046a4ced2ae2845602' 
  AND token = 'CxlPZetbnyvm8vo+xmA9wJMEu4CJNK//IEGmX/Hh4VM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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