SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea108f64477f2496cb384fb3c9a37f854c87634c503f319e828e03d567e3f9ea' 
  AND token = 'C6X5GVzEM6C4Y6nD2fInOc+O8s68elw1lA73/vQA5og=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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