SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f06e7b75379dc4d1f0cbe7b4350b28c8e72a37d2a7706c8adeacbf623987f86' 
  AND token = 'rWRRUD4+AcZTjg/znOvH2+oHQXZpQVMbAMfJslp7FZE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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