SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8bcbd2284f57da61f9142aa33e8a51cddc7d5c2b3d7b9825ff6bd8916302032d' 
  AND token = 'YW4JaUVTC1N721kkJQRbe7nB32CqzLRZnQB2K/8KbxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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