SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd00d9a4298e36e11f7d054454a877bcfa79cda97cde15f5cbd46d4cc029840b' 
  AND token = 'O84prFWGBJ3nB0LpxcpvJK43s5JTGRt2xmDzHBQOphQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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