SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44076e697eea1185a45f13db4fcb732c2c6394ba814c3d517f9bfcd8e6544f20' 
  AND token = 'tV0eqOnOUqJNnQIwH5nYWr7AZvg9u8tlUR1PuVmR3sU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}