SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '055ff6677d8bc6e5aae626b17c8f802f4da62bd12aff4d40b4748a12fd06186a' 
  AND token = 'w3owKXeVEnRTZYvNpBoHJp/sfIORdHZqwM+/jF4qqOY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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