SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '83c322350772988458927a832898170c576a099652dc1bf8115c6c5a274b17e8' 
  AND token = 'D1vWkZSESy5PRPhIpnI1uGFAwdeTUnwzZLa/a/YXCtU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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