SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a37b07d65c0d7365d4ea5a38db76580514704c5079a0bf92edb7593933eb3ac' 
  AND token = 'odDc8QFafuvj3UvCPmADDQgVkZry2THIzqQ1m2Ce7Pg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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