SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c95a9700b4cfbb9ec662dcbc6221f679a662b4285e72dcd693177f1cc0ef051' 
  AND token = '4M9gfa2ogA+vPCUQVXoVNYWIho4y6aeZibNSY1zlhCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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