SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de058111da6f80d82ccc55bc3cc64160db300a32ce83dc9051b58021400ee6a2' 
  AND token = 'HI5gRdAhQ4K++TmpiVESLfxzpxaHUdCf/19tETqMLDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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