SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2650e765c10492fc8545aa0164aab120d1b93645fb39342643cbb4ebf956d4e7' 
  AND token = 'XAoy8Qr7OoxuYUWm2aGW15PQWdoBoymEJ+jMVUQN0+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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